Thesis on Effect of Gamma Radiation on the Cucumis Sativus

Major purpose of this thesis is to analysis Effect of Gamma Radiation on the Essential Contents of Cucumis sativus ( Cucumber ) by Tandem Accelerator. Other objectives are identify the essential minerals elements of cucumber (Cucumis sativus) and observe the effect of gamma radiation on trace element of cucumber by Tandem Accelerator. finally observe the effect of gamma radiation on minerals content of cucumber (Cucumis sativus) by neutron activation analysis.

Introduction

Gamma radiation has been widely used in industrial processes, especially in food processing. Gamma radiation can induce certain alterations that can modify both the chemical composition and the nutritional value of foods. These changes depend on the food composition, the radiation dose and factors such as temperature and time. The sensitivity of vitamins to radiation is unpredictable and food vitamin losses during the irradiation are often substantial. (Ana Paula, et al., 2009)Food is the primary source of essential nutrients for man. Cucumbers are scientifically classified as fruits. Cucumbers that constitute an essential part for the body that have been analyzed for essential elements using Instrumental Neutron Activation Analysis (INAA) by tandem accelerator (Adotey.  et al. 2009).

Cucumbers are a nutritious fruits that can help weight loss, reduce risk of chronic disease and help body form healthy joints. Cucumbers are a naturally low-calorie vegetable that should find its way on any health conscious person’s eating plan (Akhtar. 1995). A single medium cucumber contains more than 8 mg of vitamin C. That’s more than 10 percent of your daily vitamin C requirement. Vitamin C is important for building connective tissue and fighting oxidation. Ensure that you eat cucumber with the peel as it is the primary source of vitamin C in cucumbers (Beste C.E.1973). The dietary value of Cucumber is negligible, there being upwards of 96 per cent water in its composition. The oil in the cucumber contains 22.3% linoleic acid, 58.5% oleic acid, 6.8% palmitic acid and 3.7% stearic acid.It also contains vitamin A, vitamin B6, thiamin, folate, pantothenic acid, magnesium, phosphorus, potassium, copper, and manganese, chromium, zink etc (Jing Wen. et al. 2010). A medium-sized cucumber has around 39 calories. A medium-sized cucumber has almost no fat and sodium content and no cholesterol. It has 2.4 grams of dietary fiber, which contributes 10 percent of daily recommended fiber intake. A medium-sized cucumber also provides 13 percent of recommended daily intake of vitamin A, 27 percent of your recommended daily intake of vitamin C and 4 percent of your daily recommended intake of minerals (Naidu. et al. 1999).

A fresh Cucumber juice has become a new functional food available for dieting and health. However, it poses a microbiological hazard to the consumer because it is distributed and consumed without any cooking. In this study, we applied the radiation sterilization of fresh Cucumber, and the effectiveness of Gamma radiation for inactivating Salmonella typhimurium and Escherichia coli in the cucumber. S. typhimurium in the Cucumber were 0.44570.004 and 0.44170.006 KGy, while those of E. coli were 0.30170.005 and 0.29970.006 kGy. The test organisms (inoculated at 107 cfu/ml) were eliminated by irradiation at 3 KGy. The antioxidant capacity of the radiated Cucumber juice was higher than that of the non-radiated control. Therefore, it was concluded that irradiation treatments of Cucumber improve the microbiological safety with maintaining or even enhancing the antioxidative activity (Hyun-pa song. et al. 2005).

Nutritionally, the cucumber has a relatively high mineral content. Its skin is most valuable as the cell salts and vitamins are in and near it. Hence it should not be peeled.
It is also a valuable source of potassium, sodium, magnesium, sulphur, silicon, chlorine and fluorine. The cucumber taken with vegetables, cereals, fruits, nuts and salads enhances the nutritional value of food items. It is generally used as a salad in combination with carrot, beet, tomato, radish, lettuce and other vegetables. The addition of some curd to the salad will make it a tasty food of great nutritional value (Marschner. et al. 2004).

Food value of Cucumber

Table 1: Food value of Cucumber

(Source: Marschner. et al. 2004)                                     

 Daily requirements of Cucumber

Table 2: Daily requirements of Cucumber

(Source: Marschner. et al. 2004)                                     

Indian diet is primarily vegetarian and consists of various cereals and vegetables along with spices, often used in the preparation of curries. The nutritive potential of each ingredient, in terms of trace element contents, has been evaluated using instrumental neutron activation analysis (INAA). Four minor (Na, K, P and Cl) and 16 trace elements (Br, Co, Cr, Cs, Cu, Fe, Hg, Mn, Mo, Rb, Sb, Sc, Se, Sr, Th and Zn) have been determined in six cereals, nine vegetables and 20 spices and condiments, including two betel leaves. None of the carbohydrate-rich cereals or potato was rich in any of the essential elements but leafy vegetables showed higher contents of Fe and other nutrients. Fe/Zn is well correlated with Fe contents in cereals and spices. Out of various spices, cinnamon was most enriched in Fe, Co, Cr, Na, K, P and Zn, whereas turmeric and curry leaves were found to be particularly rich in Se. Cumin and mustard seeds were rich in Cu. Some environmental contaminants, such as Hg, Cr, Br and Th, were also present in significant amounts. An attempt has been made to evaluate the contribution of essential elements (Cr, Cu, Fe, Mn, P, Se and Zn) in spices to the daily dietary intake (DDI) through an Indian vegetarian diet. For a typical mixture of six commonly used spices, contributions of Cr, Fe, Mn and Zn, were found to be 7.5% of DDI in each case (Vivek. 2006).

Tandem accelerator is a type of accelerators to accelerate ions by applying an electrostatic field with a feature of supplying high voltage in the middle of accelerating tube. It can accelerate ions in two steps: first, accelerating negative ions and second, further accelerating positive ions after transforming negative ions into positive in the high-voltage terminal (Shahida. et al. 2009). Tandem accelerator achieves two-step acceleration with a single voltage by converting the electric charge of a negative ion source on the high-voltage terminal. Applying a positive ion source means placing an ion source on the high-voltage terminal; this makes the maintenance work very difficult. (Acquadro, J.C.et al, 2000).The tandem accelerators can accelerate a proton up to 200 MeV, approximately 60% of the speed of light, or about 180 thousand km per second. This is equal to the speed traveling around the earth four times per second (Jacimovic. et al. 2009).

Generally, negative ions are created (atoms are ionized) in an ion source. In fortunate cases this already allows the suppression of an unwanted isobar, which does not form negative ions (as ¹⁴N in the case of ¹⁴C measurements). The pre-accelerated ions are usually separated by a first mass spectrometer of sector-field type and enter an electrostatic “tandem accelerator”. This is a large nuclear particle accelerator based on the principle of a Tandem  Accelerator operating at 0.2 to many million volts with two stages operating in tandem to accelerate the particles. At the connecting point between the two stages, the ions change charge from negative to positive by passing through a thin layer of matter (“stripping”, either gas or a thin carbon foil). Molecules will break apart in this stripping stage. When the ions leave the accelerator they are positively charged and are moving at several percent of the speed of light. In a second stage of mass spectrometer, the fragments from the molecules are separated from the ions of interest. This spectrometer may exist of magnetic or electric sectors, and so called velocity selectors, which utilizes both electric fields and magnetic fields (Brown. et al. 2005). Essential elemental analysis of cucumber are performed by employing Instrumental Neutron Activation Analysis (INAA) by tandem accelerator. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced radio activity was counted by gamma ray spectrometry using an efficiency calibrated high resolution High Purity Germanium (HPGe) detector (Damcott. et al. 1995).

Neutron Activation Analysis (NAA) is a quantitative and qualitative method of high efficiency for the precise determination of a number of main-components and trace elements in different types of samples. NAA, based on the nuclear reaction between neutrons and target nuclei, is a useful method for the simultaneous determination of about 25-30 major, minor and trace elements of geological, environmental, biological  samples in ppb-ppm range without or with chemical separation (Palmblad. 2005).

In NAA, samples are activated by neutrons. During irradiation the naturally occurring stable isotopes of most elements that constitute the rock or mineral samples, biological materials are transformed into radioactive isotopes by neutron capture. Then the activated nucleus decays according to a characteristic half-life; some nuclides emit particles only, but most nuclides emit gamma-quanta, too, with specific energies. The quantity of radioactive nuclides is determined by measuring the intensity of the characteristic gamma-ray lines in the spectra. For these measurements a gamma-ray detector and special electronic equipment are necessary. As the irradiated samples contain radionuclides of different half-lives different isotopes can be determined at various time intervals ( Alam. 2010).

Food irradiation is a process in which approved foods are exposed to radiant energy, including gamma rays, electron beams, and x-rays to make them free from microbes & thus extend their self life. Irradiation of meat and poultry is done in a government-approved irradiation facility. Food irradiation is a technology for controlling spoilage and eliminating food-borne pathogens that may be present in food, including E. coli O157:H7, Salmonella, and Campylobacter. The result is similar to conventional pasteurization and is often called “Cold Pasteurization” or “Irradiation Pasteurization” as though the function of food irradiation is same like pasteurization, but the temperature of the irradiated food is not raised. In the process, bulk or packaged food passes through a radiation chamber on a conveyor belt. The food does not come into contact with radioactive materials, but instead passes through a radiation beam, like a large flashlight.The type of food and the specific purpose of the irradiation determine the amount of radiation, or dose, necessary to process a particular product. Cobalt-60 is the most commonly used radionuclide for food irradiation ( Alamin. 2007).

Irradiation exposes food to radiant energy. Food is passed through an irradiator–an enclosed chamber–where it is exposed to a source of ionizing energy. The sources of ionizing energy may be gamma rays from cobalt 60 (⁶⁰Co), cesium 137 (¹³⁷Cs), x-rays, or electrons generated from machine sources (Swallow. 1991).The emitted gamma rays are very short wavelengths, similar to ultraviolet light and microwaves. Because gamma radiation does not elicit neutrons (i.e., the subatomic particles that can make substances radioactive), irradiated foods and their packaging are not made radioactive (Thorne. 1991). Energy penetration is about 1.5 inches in food products, so the thickness of items to be treated is limited to about 3.0 inches with double-sided treatment. The small amount of energy that does not pass through the food is negligible and is retained as heat. At an irradiation facility, the radiation source (usually the cobalt-60) is contained in slender pencil- like stainless steel casing about 18 inches long by 3/8 inch diameter. The casings, in turn, are contained in a lead-lined chamber. Packaged food travels in pallets on a conveyor between 6-1/2 foot thick concrete walls into and through a chamber where it is exposed to the radiation source (gamma rays if cobalt-60 is used). Pallets may be turned to allow uniform exposure over the route. Radiation dosage is controlled by a computerized rate of passage (conveyor speed) through the chamber. The duration of exposure to ionizing energy, density of food, and the amount of energy emitted by the irradiator determine the amount or dose of radiant energy to which the food is exposed (Moreau. et al. 2000).

Irradiation has been compared to pasteurization fruits or other food because it destroys harmful bacteria. Since irradiation does not substantially raise the temperature of the food being processed, nutrient losses are small and often substantially less than other methods of preservation such as canning, drying, and heat pasteurization and sterilization. The relative sensitivity of the different vitamins to irradiation depends on the food source, and the combination of irradiation and cooking is not considered to produce losses of notable concern (Diehl. 1995).

Objective of the present study:

1. To identify the essential minerals elements of cucumber (Cucumis sativus).
2. To observe the effect of gamma radiation on trace element of cucumber (Cucumis sativus) by Tandem Accelerator.

3. To reveal the nutritional composition of cucumber (Cucumis sativus) by neutron activation analysis.
4. To observe the effect of gamma radiation on minerals content of cucumber (Cucumis sativus) by neutron activation analysis.

Review of Literature

Food is the primary source of essential nutrients for man. Vegetables are essential part of the Ghanaian diet; therefore the nutritional status of vegetables is important. Vegetables that constitute an essential part of the Ghanaian diet have been analyzed for essential elements content (Ca, Mg, K, Co, Br, Mn, and Na) using Instrumental Neutron Activation Analysis (INAA). The purpose of the study was to design a nutrient database of the core vegetables grown and consumed in Ghana and in addition to ascertain the content of the essential elements in the vegetables. The accuracy of the method was verified by analysis of a compositionally appropriate reference material, IAEA -359 (CABBAGE). The results of the study revealed the presence of Br, Ca, Co, K, Mg, Mn, and Na in all the five vegetables studied. Ca, Mg, and K were present in the g/kg range in all five vegetables. The content of Na, Mn, Co and Br was in the mg/kg range in all five vegetables investigated (Adotey. et al. 2009).

The control of food quality, using the analysis of essential and toxic element contents, assumes an urgent importance within the regions that suffered from the Chernobyl disaster. Instrumental neutron activation analysis was used to study contents of 17 chemical elements (calcium, chlorine, cobalt, chromium, cesium, iron, mercury, potassium, magnesium, manganese, sodium, rubidium, antimony, scandium, selenium, strontium, and zinc) in foods within the south and southwest territories of the Kaluga Region that was exposed to radionuclide contamination. The radionuclide contamination ranges up to 15 Ci/km2 there. Flesh and meat products, dairy products, bread, vegetables, legumes, roots, fruits, and mushrooms were analyzed. The concentration of essential and toxic elements in the different foods were in the normal ranges ( Zaichick. 2002).

Ionizing radiation has been widely used in industrial processes, especially in the sterilization of medicals, pharmaceuticals, cosmetic products, and in food processing. Similar to other techniques of food processing, irradiation can induce certain alterations that can modify both the chemical composition and the nutritional value of foods. These changes depend on the food composition, the irradiation dose and factors such as temperature and presence or absence of oxygen in the irradiating environment. The sensitivity of vitamins to radiation is unpredictable and food vitamin losses during the irradiation are often substantial. The aim of this study was to discuss retention or loss of vitamins in several food products submitted to an irradiation process (Ana Paula. et al. 2009).

The carrot powder was prepared from carrot juice concentrate. The physiochemical parameters of carrots juice, concentrate and powder were studied during process and revealed a decrease in moisture (%) 92, 24 and 5 respectively. Similarly ash, fiber, total sugar and fat percentage were increased as (0.76, 1.2, 2.2), (0.3, 0.6, 0.5), and (0.3, 0.42, 0.5) for juice, concentrate and powder respectively. The vitamin C was 15 mg/ 100g in juice, 28mg/ 100g in concentrate and 31mg/ 100g in powder. The ß carotene was 4.2 mg/ 100g in raw carrot, 3.5mg/ 100g in juice, 2.9mg/ 100g in blanched juice, 35.5mg/ 100g in concentrate and 6mg/ 100g in carrot powder. Carrots being seasonal vegetables that are unavailable during off-season, the present study were carried out to develop a national interest technology for the preparation of carrot powder to make available the carrots nutritional value for the whole year (Patrícia. et al. 2007).

The effect of γ-ray irradiation on the fatty acid profile of beef meat was examined at doses of 2.5, 5.0, 7.5, 10.0 and 15.0 kGy by means of H NMR spectroscopy. NMR results revealed a clear trend toward an increase in the amount of saturated fatty acids and a decrease in the amount of polyunsaturated fatty acids in the triacylglycerol composition of the irradiated samples compared to the unirradiated sample with increasing the irradiation dose. The observed changes in the fatty acid profile were confirmed by gas chromatography analysis of the samples irradiated at doses of 7.5, 10.0 and 15.0 kGy (Kogo. et al. 2009).

A fresh vegetable juice has become a new functional food available for dieting and health. However, it poses a microbiological hazard to the consumer because it is distributed and consumed without any cooking. In this study, we applied the radiation sterilization of fresh vegetable juice, and the effectiveness of Gamma irradiation for inactivating Salmonella typhimurium and Escherichia coli in the carrot and kale juice was investigated. D10 values of S. typhimurium in the carrot and kale juice were 0.44570.004 and 0.44170.006 kGy, while those of E. coli were 0.30170.005 and 0.29970.006 kGy. The test organisms (inoculated at 107 cfu/ml) were eliminated by irradiation at 3 kGy. The total phenol contents of the irradiated juice during 3 days of storage at a cold chain temperature (10 1C) increased significantly while those of the non-irradiated juice decreased. The antioxidant capacity of the irradiated carrot juice was higher than that of the non-irradiated control. Therefore, it was concluded that irradiation treatments of carrot and kale juice improve the microbiological safety with maintaining or even enhancing the antioxidative activity (Hyun-pa song. et al. 2005).

Specific parts (fruits and seeds) of different medicinal plants often used in Indian Ayurvedic system were analysed for 18 elements (K, Mn, Na, Fe, Zn, Cu, Co, Br, Sm, Cl, La, Al, Cr, Ca Cd, Ni, Pb and Hg) by employing instrumental neutron activation analysis (INAA) and atomic absorption spectroscopy (AAS) techniques. The samples were irradiated with thermal neutrons in a nuclear reactor and the induced activities were counted by γ-ray spectrometry using efficiency calibrated high-resolution high purity germanium (HPGe) detector. Most of the medicinal plants were found to be rich in one or more of the elements under study. The elemental concentration in different part of medicinal plants and their biological effects on human being are discussed. It is expected that the experimental data on the elemental concentrations will be helpful in the synthesis of new Ayurvedic drugs for the control and cure of various diseases (Karel. 1989).

Tonoplast vesicles were prepared from potato tubers (Solarium tuberosum L.) on a step gradient (0% and 6%, w/w) of dextran T-70 to clarify the mechanism by which the tonoplast H⁺-ATPase is inactivated by gamma-irradiation. H⁺-ATPase activity and H⁺ -pumping were examined after irradiation of tubers (in vivo irradiation) and of isolated tonoplast vesicles (in vitro irradiation) at doses up to 1.0 kGy. Both in vivo irradiation and in vitro irradiation resulted in significant decreases in ATPase and H⁺-pumping activities. The ATPase and H⁺-pumping activities 12 h after irradiation were much lower than those 2 h after irradiation. Solubilized H⁺-ATPase was inactivated, in a dose-dependent manner by irradiation (enzyme irradiation) to a greater extent than was observed after in vitro irradiation or in vivo irradiation. The activity of ATPase 12 h after enzyme irradiation was almost the same as it was 2 h after enzyme irradiation. The free fatty acid content of vacuolar membranes was increased by in vivo irradiation and by in vitro irradiation with an accompanying decrease in tonoplast H⁺-ATPase activity. Lipids from irradiated tonoplasts had a considerable inhibitory effect on the activity of solubilized H⁺-ATPase. This result suggests that the direct inactivation of H⁺-ATPase in potato tonoplast by gamma-irradiation is augmented by the effects of deterioration of membrane lipids that is induced by the irradiation (Setsuko. et al. 2003).

Trikatu, an Ayurvedic formulation of three dried powder spices, ginger, black pepper and pipali in equal proportion is widely used to promote digestion, assimilation and bioavailibility of food. It works synergistically, and hence, is more effective than an equal amount of any of its three ingredients taken separately. Five different brands and its three constituents were analyzed for 31 elements by instrumental neutron activation analysis (INAA) using 5-minute and 6-hour thermal neutron irradiation followed by high-resolution  ray spectrometry. Heavy toxic metals Cd, Ni and Pb determined by atomic absorption spectrometry (AAS) were found below permissible limits. Most elements in different brands vary in a narrow range. Ginger is particularly enriched in Ca, Fe, Mg and Mn whereas black pepper is enriched in Cr, Se, P and Zn. Cu/Zn shows linear relationship (r = 0.92) with Cu whereas Fe and Mn exhibit inverse correlation (r = –0.89) in different brands. Hydro distillation of pipali yielded an essential oil whereby 10 organic constituents were identified by GC-MS. Also barbituric and tannic acids were isolated from the aqueous methanolic extract of pipali (Paul Choudhury. et al. 2006).

The deficiency of essential micronutrients and excess of toxic metals in cereals, an important food items for human nutrition, can cause public health risk. Therefore, before their consumption and adoption of soil supplementation, concentrations of essential micronutrients and metals in cereals should be monitored. This study collected soil and two varieties of wheat samples–Triticum aestivum L. (Jordão/bread wheat), and Triticum durum L. (Marialva/durum wheat) from Elvas area, Portugal and analyzed concentrations of As, Cr, Co, Fe, K, Na, Rb and Zn using Instrumental Neutron Activation Analysis (INAA) to focus on the risk of adverse public health issues. The low variability and moderate concentrations of metals in soils indicated a lower significant effect of environmental input on metal concentrations in agricultural soils. The Cr and Fe concentrations in soils that ranged from 93–117 and 26,400–31,300 mg/kg, respectively, were relatively high, but Zn concentration was very low (below detection limit <22 mg/kg) indicating that soils should be supplemented with Zn during cultivation. The concentrations of metals in roots and straw of both varieties of wheat decreased in the order of K>Fe>Na>Zn>Cr>Rb>As>Co. Concentrations of As, Co and Cr in root, straw and spike of both varieties were higher than the permissible limits with exception of a few samples. The concentrations of Zn in root, straw and spike were relatively low (4–30 mg/kg) indicating the deficiency of an essential micronutrient Zn in wheat cultivated in Portugal. The elemental transfer from soil to plant decreases with increasing growth of the plant. The concentrations of various metals in different parts of wheat followed the order: Root>Straw>Spike. A few root, straw and spike samples showed enrichment of metals, but the majority of the samples showed no enrichment. Potassium is enriched in all samples of root, straw and spike for both varieties of wheat. Relatively to the seed used for cultivation, Jordao presented higher transfer coefficients than Marialva, in particular for Co, Fe, and Na. The Jordao and Marialva cultivars accumulated not statistically significant different concentrations of different metals. The advantages of using INAA are the multielementality, low detection limits and use of solid samples (no need of digestion) (Adeyemo. 2004).

Instrumental neutron activation analysis has been utilized for the quantification of 24 major, minor and trace elements in dried apricots (Prunus armeniaca), dates (Phoenix dectylifera), figs (Ficus carica) and raisins (Vitis vinifera) using a low-power reactor as the neutron source. The weekly intakes of aluminium, arsenic, boron, calcium, chlorine, cobalt, chromium, iron, mercury, potassium, sodium, magnesium, manganese, molybdenum, antimony, selenium and zinc have been calculated and compared with the Recommended Dietary Allowance/Estimated Safe and Adequate Dietary Intake values through consumption of 100 g dried fruit. Fairly adequate levels of calcium, cobalt, iron, potassium and magnesium were determined in these dried fruits while the contribution of chlorine, chromium, molybdenum and sodium to the Recommended Dietary Allowance was found to be insignificant. Apricot is a nutritionally rich source of potassium, magnesium and cobalt, while chlorine and manganese contents were found to be highest in dates. Figs are an ample source of calcium, iron, magnesium and manganese, whereas raisins provide the highest intake of chromium, molybdenum and sodium. The toxic element contents of these dry fruits are considerably below the tolerance limits ( Shahida. 2009).

Eighteen major, minor and trace elements in 12 Chinese medicinal herbs commonly consumed by Taiwanese Children as diuretics were determined by instrumental neutron activation analysis (INAA). Dried and powdered herb samples were irradiated in a neutron flux of ca. 2 × 10¹² n/cm² s under separate short and long irradiation schemes. Lichen (IAEA-336) was used as the reference standard, and tomato leaves (NIST-SRM 1570a) were employed for cross-checking the accuracy of the results. INAA was shown to be a reliable multi-element analytical method for determining the content of both toxicologically and nutritionally important minerals in Chinese medicinal herbs. Determined elements were present in the dried herbs in concentrations ranging from 10⁴ to 10⁻³ µg/g. The mineral contents and the maximum daily intake values of the tested herbs were compared with published values and with the recommended daily intakes for Taiwanese children as specified by the World Health Organization (Chien. 2005).

Instrumental neutron activation analysis has been used for the analysis of seven varieties of medicinal herbs generally used by the people of South Asian region. Twenty-one trace elements (essential, toxic and non-essential) were determined. This data should not only be helpful in establishing the base-line values in these medicinal herbs but also in correlating their role as therapeutic agents. A comparison of our data with literature values shows variation in trace element contents of same species of different origin which can be attributed to ecological and geographical variations to some extent; however an exact interpretation demands further extensive investigations (Jamshed. 2004).

The effect of gamma rays irradiation and phosphorus on chamomile growth and oil production was studied. Chamomile seeds were pre-sowing irradiated with 0, 2, 4, 6, 8 or 10 k-rad gamma rays. Phosphorus was soil added at concentrations of 10 or 20 kg/ feddan as calcium super-phosphate. Gamma irradiation enhanced plant height, branching capacity and shoot and root fresh and dry weights compared with plants produced from non-irradiated seeds. The combination of gamma irradiation and phosphorus had a stimulating effect on the growth parameters measured. Gamma rays irradiation and phosphorus had also pronounced effect on carbohydrates, soluble sugars, and mineral contents and on the percentage of oil production from chamomile flowers compared with the control (Abla. et al. 2001).

Neutron activation analysis in combination with atomic absorption spectrometry was utilized for the determination of 21 elements in integrated diet samples of the inhabitants of the Rawalpindi/Islamabad area. The study was carried out to determine prevailing concentration levels of trace elements nutrition, inadequacy, imbalances and toxicity. This data will serve as baseline values and will be helpful to monitor the degree of future contamination from foreign chemicals. The dietary intake values were also estimated and compared with the reported daily intake values. In general, the diets studied are adequate source of nutrient elements. The toxic elements intake through all the diet samples are within the safety limits (Qureshi. et al. 2004).

The selenium content of a variety of food items representing a normal hospital diet has been determined by cyclic instrumental neutron activation analysis (CINAA) through the 162-keV gamma-ray of the^77mSe nuclide. The CINAA method is very simple and rapid. It involves irradiation of a sample for 20 s, decay for 20 s, and counting for 20 s. The precision of the method has been significantly improved by recycling the samples up to 4 times. The accuracy has been evaluated by analyzing a number of certified reference materials of varied selenium levels (Mc Dowell.  et al. 1998).

A pseudo-cyclic instrumental neutron activation analysis (PCINAA) method has been developed to determine selected elements in various types of cereal and vegetable from Ghana using relatively short-lived nuclides (t_1/2<80 s) and the Compton suppression counting. The samples were irradiated for 10 s at the Dalhousie University SLOWPOKE-2 research reactor facility (DUSR) and allowed to decay for 20 s, and counted for 40 s. The process is repeated every 50 s for 4 cycles to quantify Dy, Hf, Rb, Sc and Se through ^165mDy, ¹⁷⁹Hf, ^86mRb, ^46mSc, and ^77mSe. The detection limits were generally of the order of 1.0 ng g⁻¹ except for Rb which is about 1 μg g⁻¹. Both precision and accuracy of the method were found to be good (Nyarko. 2008).

Bioaccessibility of some essential elements namely K, Mn, Zn, Fe and Na from wheatgrass, consumed as dietary supplement, was measured by in vitro gastric and gastro-intestinal digestion methods. Neutron activation analysis was used to determine bioaccessible concentration of these elements. Bioaccessibility of these elements in commercial wheatgrass tablets and wheat grains was also determined. From both the methods, it was found that bioaccessibility of the elements studied was the highest from fresh wheatgrass and the lowest for wheat seeds. The range of values determined by gastric digestion for wheatgrass, wheatgrass tablets and wheat seeds were 37–57%, 17–43% and 9–38% respectively. Corresponding bioaccessibility values determined by gastro-intestinal digestion method were 39–60%, 34–55% and 15–23% respectively. These studies suggested that fresh wheatgrass grown in the laboratory is an effective source of minerals ( Kulkarni. 2007).

Indian diet is primarily vegetarian and consists of various cereals and vegetables along with spices, often used in the preparation of curries. The nutritive potential of each ingredient, in terms of trace element contents, has been evaluated using instrumental neutron activation analysis (INAA). Four minor (Na, K, P and Cl) and 16 trace elements (Br, Co, Cr, Cs, Cu, Fe, Hg, Mn, Mo, Rb, Sb, Sc, Se, Sr, Th and Zn) have been determined in six cereals, nine vegetables and 20 spices and condiments, including two betel leaves. None of the carbohydrate-rich cereals or potato was rich in any of the essential elements but leafy vegetables showed higher contents of Fe and other nutrients. Fe/Zn is well correlated with Fe contents in cereals and spices. Out of various spices, cinnamon was most enriched in Fe, Co, Cr, Na, K, P and Zn, whereas turmeric and curry leaves were found to be particularly rich in Se. Cumin and mustard seeds were rich in Cu. Some environmental contaminants, such as Hg, Cr, Br and Th, were also present in significant amounts. An attempt has been made to evaluate the contribution of essential elements (Cr, Cu, Fe, Mn, P, Se and Zn) in spices to the daily dietary intake (DDI) through an Indian vegetarian diet. For a typical mixture of six commonly used spices, contributions of Cr, Fe, Mn and Zn, were found to be 7.5% of DDI in each case (Singh. 2005).

The radioactive sample is counted until a suitable gamma-ray spectrum is obtained. A typical gamma-ray spectrum of a complex substance. A gamma-ray spectrum is just a plot of the relative number of gamma counts versus the energy of the gamma rays. A typical spectrum is a series of sharp photopeaks superimposed on a broad, sloping background. Each photopeak represents the decay of a specific radioisotope, although most radioisotopes have more than one photopeak. In this example, strong peaks of iron, scandium, cobalt, zinc, and antimony can be seen. Several other elements are also present, but with smaller photopeaks. A computer program calculates the number of counts above background in each peak, compares it with standard mixtures of elements irradiated and counted similarly, and calculates the masses of each element detected in the sample. Because useful half-lives of elements range from seconds to decades, a full analysis consists of two or more irradiations of lengths ranging from minutes to days, followed by several counts at decay times ranging from minutes to months (Ram. 2010).

Research programs on the application of food irradiation have been conducted by the Queensland Department  of  Primary  Industries  and  Fisheries  since  1985.  Horticultural  products  studied include: avocado, broccoli, capsicum, carambola, Chinese cabbage, cucumber, custard apple, ginger, lemon, lychee, mandarin, mango, melons, mushrooms, navel oranges, nectarine, ornamentals (flowers), papaya, passionfruit, peach, persimmon, rambutan, strawberry, tomatoes and zucchini. In addition to fruit quality studies a number of entomological studies have been undertaken with a strong focus on fruit flies (Begg. 1990).

The effect of ultraviolet  B ( UV-B) radiation on the thermal sensitivity of cucumber (Cucumis sativus L.) was studied using  UV-sebsitivity of cv  poinsett 76 and UV-B-resistant cv Ashley grown under control and elevated (300 mWm^-2)   UV_B radiation levels. Using both cotyledons  and leaf discs,the ability of the tissue to reduce triphenyl tetrazolium chloride (TTC) was determined  after  treatment at  50°c were curvilinear. They were monophasic for the control cucumber and the biphasic for cucumber grown in the presence of elevated UV-B.Treatment of cucumber plants at 37°c for 24 h or tissue discs at acute UV-B levels for 1 h further  modified their response to elevated temperature.These result suggest  that  growth of cucumber under enhanced UV-B radiation levels increased its ability to withstand elevated temperatures (Addae.Mensah. 1992).

We have applied Instrumental Neutron Activation Analysis (INAA) in the analysis of various essential trace elements Mg, Ca, Mn, K, Cr, Co and Zn and non-essential trace elements Al, Br, La, Yb, Rb, Ba, Eu and Sb in some Nigeria commercial milk and infant cereal formulas. The samples were irradiated for both short and long regimes with the irradiation time of 2 minutes and 6 hours respectively in a neutron flux of 5 x 1011 ncm-2s-1 with the Research Reactor at the Centre for Energy Research and Training, CERT, Ahmadu Bello University, Zaria. The results shows the samples analyzed contains adequate amounts of essential trace elements measured with Mn being slightly deficient, particularly in sample A1 of the milk formula and A2 of the cereal formula. In addition, the results obtained for non-essential trace elements in most samples are within the recommended tolerable level. However, the concentrations of Ba and Sb are high in samples C1 of both the milk formula. Furthermore, the concentration of Sb is also found to behigh in samples C2 of the cereal formula. Hence, there is the need for the manufacturers in Nigeria to continue to strive to reduce the non-essential elements concentration in their productssince they pose serious health challenges to infants who take these foods (Joseph. et al. 2011).

The aim of this study was to investigate the effect of gamma irradiation on storability of the two main apple varieties, Golden Delicious and Starking, in Syria. The experiments were performed in 1995 and 1996. Fruits were irradiated with 0, 0.5, 1.0 and 1.5 KGy. Irradiated and unirradiated fruits were stored at 1 to 2 °C and under a relative humidity of 80 to 90%. Weight loss and spoilage due to physiological disorders and fungal diseases were evaluated throughout the different storage periods. Firmness, coloration and pH values were estimated immediately after irradiation. The results showed that, in both varieties, gamma irradiation increased the weight loss after 45 days of storage in apples gathered in 1995 but not in the 1996 season. After 180 days of storage, gamma irradiation had different effects on weight loss depending on the growing year and variety, and increased fungal spoilage. Application of gamma irradiation prevented the growth of Aspergillus niger and the formation of skin scald in Golden Delicious fruits. Immediately after treatment, gamma irradiation increased the softening of fruits, changed their color from green to yellow and decreased the pH value of the juice (Al-Bachir. et al. 20006).

The effect of gamma radiation from a Cobalt⁶⁰ source upon lettuce tissue was studied. The radiation-induced softening of leaf discs was assessed with an instrument designed to measure the bending of the disc under application of a given weight. It is estimated that the “threshold dose” of radiation-induced softening of lettuce is between 600 and 1,000 Kilorad. Lettuce leaf tissue thus appears more resistant to the softening effect of gamma radiation than the storage type tissues of apples, carrots, or beets. The radiation-induced changes in the respiratory activity of lettuce were also studied, both during and after irradiation. Although both oxygen consumption and carbon dioxide evolution are stimulated during irradiation, the response subsides to near-normal rates shortly after irradiation is stopped. There is some indication that the magnitude of the respiratory rate stimulation response is based primarily upon dose rate. A comparison of softening and respiratory rate measurements indicates that the tissue softening is probably not directly related to the respiratory stimulation that occurs during gamma irradiation (Massey. 1961).

Indian diet is primarily vegetarian and consists of various cereals and vegetables along with spices, often used in the preparation of curries. The nutritive potential of each ingredient, in terms of trace element contents, has been evaluated using instrumental neutron activation analysis (INAA). Four minor (Na, K, P and Cl) and 16 trace elements (Br, Co, Cr, Cs, Cu, Fe, Hg, Mn, Mo, Rb, Sb, Sc, Se, Sr, Th and Zn) have been  determined in six cereals, nine vegetables and 20 spices and condiments, including two betel leaves. None of the carbohydrate-rich cereals or potato was rich in any of the essential elements but leafy vegetables showed higher contents of Fe and other nutrients. Fe/Zn is well correlated with Fe contents in cereals and spices. Out of various spices, cinnamon was most enriched in Fe, Co, Cr, Na, K, P and Zn, whereas turmeric and curry leaves were found to be particularly rich in Se. Cumin and mustard seeds were rich in Cu. Some environmental contaminants, such as Hg, Cr, Br and Th, were also present in significant amounts. An attempt has been made to evaluate the contribution of essential elements (Cr, Cu, Fe, Mn, P, Se and Zn) in spices to the daily dietary intake (DDI) through an Indian (Magda. 2003).

Experiments were conducted at Hill Agricultural Research Station, Khagrachari during the period from November to February in 2005-06 and 2006-07 to determine the appropriate irrigation schedule for carrot production in hill valley. The experiment consisted of five treatments of irrigation after plant established viz. No irrigation (I₀), irrigation at 1W: CPE of 0.6 (I₁), irrigation at 1W: CPE of 0.8 (1₂), irrigation at 1W: CPE of 1.0 (I₃) and irrigation at 1W: CPE of 1.2 (I₄). The amount of irrigation water (IW) was fixed at 4 cm. The experiment was laid out in RCBD with 3 replications. The treatments significantly influenced the growth, yield contributing characters and yield of carrot. Among the treatments, irrigation at IW: CPE of 1.2 gave the maximum yield (51.47 t/ha) which received 4 irrigations after plant stand with applied total irrigation water of 16 cm resulting in the highest net return of Tk. 120,443 with the highest BCR of 2.41. It also produced carrot at the lowest production cost of Tk. 1.66 per kg. Irrigation water use efficiency was obtained 1705.63 kg/ha/cm by this treatment (Mallik. et al.  2010).

Materials & Methods

Assessment and determination of nutritive value and observing the effect of radiation by ⁶⁰Co gamma irradiator on the essential content of cucumber (Cucumis sativus) were done according to the following materials and methods.

The study was conducted in the laboratory of the institution of Food and Radiation Biology, Atomic Energy Research Establishment, Savar, Dhaka. The study was conducted there during March-June. The objective of the present study was to assess essential mineral contents of cucumber and to observe the effect of gamma radiation on the essential mineral contents of the carrot by Tandem Accelerator. Cucumber are scientifically classified as fruits. It is an important source of vitamin A, B, C and minerals for human nutrition. It is also good source of some essential minerals such as K, Ca, Cr, Mn, Fe, Ni, Cu and Zn.

Materials

Samples Collection: Cucumber (Cucumis sativus) of fresh quality, collected from the local market of Savar were used in this study.

Equipments: Oven, Magnetic stirrer, Analytical balance, Porcelain crucible, Petri dish, Blender,  Steel dishes, Distilled water, Specula, Knife, Hydraulic pressure, Chopper board, Refrigerator, Freeze drier, Milling machine, Tandem accelerator, Polyethylene paper, Sealer, etc. are used in laboratory work and ⁶⁰Co radiation source was used for irradiation.

3.2 Methods

The present study was carried out to assess the nutritive value of cucumber and to observe the effect of gamma radiation on the essential content of the cucumber. To observe the effect of gamma radiation, the samples (cucumber) were treated with radiation of doses 1 kGy, 2 kGy, 2.5 kGy, 3 kGy and one sample was kept controlled. The study was conducted for five weeks. The assessment was conducted at -20⁰C,  -52⁰C & room temperature and 0.370  mbar pressure.

Preparation of sample

Collection of Sample

The samples (cucumber) of fully mature, sound ripe and large size were procured from the “Boliboddro bazar” of EPZ (Export Processing Zone), Savar. The samples were totally fresh and free from any type of injury or deterioration.

Cleaning of samples

The samples (cucumber) were washed and cleaned by distilled water, and then injured part was removed from the samples.

Peeling and slicing of samples

The samples (cucumber) were peeled by hand and then sliced into many uniform small pieces by very sharp knife. All of this work was done on a very hard and strong plastic hard board.

Blending and homogenizing of samples

The sliced pieces of cucumber were blended by blender machine but this important work was done by steps by steps. Then blended samples was homogenized by homogenizer and mixed the sample very uniformly. Finally the samples were made paste type.

Weighing of samples

The homogenized samples were weighed into 100 gm and 150 gm by electrical balance. 100 gm was weighed for controlled and 150 gm was weighed for irradiation purpose. Four packets were made by giving 150 gm samples into each packet.

Polyethylene packaging and sealing of samples

The samples were first packed into sterilized polyethylene paper and then sealed with sealer machine. Finally four packets containing the samples were transferred to Gamma radiation room for radiation purpose.

Irradiation of samples

Source

In this study, a ⁶⁰Co gamma radiator was used the radiation source.

Figure: Diagram of ⁶⁰Co gamma radiator

Dose selection

To observe the effect of radiation doses on essential content and vitamin A content of cucumber, 1 control (or 0.0kGy) and 4 different radiation doses (1.0kGy, 2.0kGy, 2.5kGy and 3.0kGy) were used.

Radiation of sample

Then the packets containing the samples were sent to the radiation chamber to radiate by selected doses (1.0kGy, 2.0kGy, 2.5kGy and 3.0kGy). A ⁶⁰Co gamma irradiator was used as the source of radiation.

Storage of sample

After being irradiated, the samples were kept at low temperature (-20⁰C) on a clean and close refrigerator for 48 hours.

Freeze drying of the samples

The samples were freeze dried by freeze dryer. This work was done by five steps:

1. Some portion from the controlled sample was taken into a test tube. Then it was freeze dried by freeze dryer by setting dryer at -52⁰C and 0.370 mbar pressures. It was taken about three days. Then sample was kept into a desecrator by sealing that was done by sealing paper so that no moisture could enter into the packet.
2. Some portion from the 1.0 KGy radiated sample was taken into a test tube. Then it was freeze dried by freeze dryer by setting dryer at -52⁰C and 0.370 mbar pressures. It was taken about three days. Then sample was kept into a desecrator by sealing that was done by sealing paper so that no moisture could enter into the packet.
3. Some portion from the 2.0 KGy radiated sample was taken into a test tube. Then it was freeze dried by freeze dryer by setting dryer at -52⁰C and 0.370 mbar pressures. It was taken about three days. Then sample was kept into a desecrator by sealing that was done by sealing paper so that no moisture could enter into the packet.
4. Some portion from the 2.5 KGy radiated sample was taken into a test tube. Then it was freeze dried by freeze dryer by setting dryer at -52⁰C and 0.370 mbar pressures. It was taken about three days. Then sample was kept into a desecrator by sealing that was done by sealing paper so that no moisture could enter into the packet.
5. Some portion from the 3.0 KGy radiated sample was taken into a test tube. Then it was freeze dried by freeze dryer by setting dryer at -52⁰C and 0.370 mbar pressures. It was taken about three days. Then sample was kept into a desecrator by sealing that was done by sealing paper so that no moisture could enter into the packet.

Milling of the dried samples

The freeze dried samples were milled by milling machine uniformly & very carefully and made it into powder like. After milling the sample was taken into aluminum fuel so that no moisture could into the sample. Then it was transferred to hydraulic pressure machine for making tablet.

Taking weight of the samples

Some portion (about 0.200 gm) from powder samples was taken for making four tablets by electrical balance during this time the electrical balance machine was calibrated by tearing. The sample was taken into weighting papers and specula were used for taking sample. The machine was totally error free and gave accurate results.

Making tablet by the samples (powder)

The tablet was made by hydraulic pressure machine that’s diameter was 10 mm. This work was done by giving 5 (five) tones pressure. After making tablet it was removed from the hydraulic pressure machine by just giving hand pressure.

Storage of tablet

After being made tablets, it was storage at -20^0-C temperature into a refrigerator for analyzing essential contents by Tandem accelerator. It was kept into a deep freeze so that it could not absorb moisture from the outer sides.

Results and Discussion

This chapter has been arranged sequentially with presenting the mineral contents of cucumber (Cucumis sativus) and the effect of gamma radiation on essential mineral contents of cucumber.

Essential mineral contents

The irradiated samples have been analyzed and the following elements identified K, Ca, Cr, Mn , Fe, Ni, Cu, Zn. The purpose of this study intends to a better understanding the effect of the essential element of cucumber by different doses (0KGy, 1KGy, 2KGy, 2.5KGy, 3KGy) of gamma radiation.

Mineral contents of the fresh Cucumber (control) obtained are represented in the table 3 shows that Iron (Fe) is the major constituent of control sample comprise 358512 ppm. Potassium (K) is the 2^nd highest constituent of controlled sample of carrot whose amount 183699  ppm.  Chromium (Cr), Calcium (Ca) and Nickel (Ni)show moderate value of 112931 ppm  70144 and 29267 ppm respectively. Whereas, amount of Manganese (Mn), Cupper (Cu) and Zinc (Zn) is very low only 8717 ppm, 2957 ppm and 977 ppm respectively.

Table: Essential mineral contents of the fresh Cucumber (control)

( Error greater than 30% is neglected)

Effect of Gamma Radiation on Essential Minerals Content of Cucumber

To observe the effect of gamma radiation on the essential mineral contents of Cucumber (Cucumis sativus) sample was divided into 5 groups and irradiated with different doses (Control or 0KGy, 1KGy, 2KGy, 2.5KGy, 3KGy). The obtained results of the change of on the essential mineral contents of Cucumber are represented below.

Effect of gamma radiation on Potassium (K) and Calcium (Ca)

Effect of gamma radiation on Potassium (K) and Calcium (Ca) contents (ppm) in the sample is represented in the following table 4.

Table: Conc. (ppm) of  K and Ca contents of control and radiated cucumber

(Error greater than 30% is neglected), MDL= Minimum Detection Limit

The table 4 reveals that the concentration of Potassium (K) obtained from the samples radiated with various doses (0.0, 0 1.0, 2.0, 2.5 & 3.0 kGy) is 183699, 302477, 387421, 358772, 357418 ppm. Whereas, amount of Calcium (Ca) is 70144, 139367, 179910, 178251, 169022ppm. The values of K and Ca is high for 2 KGy and low for control. The values of K and Ca is different for different doses.

So, the obtained results of present study about the effect of gamma radiation on essential mineral contents of Cucumber radiated with different radiation doses shows a gradual increase of essential mineral contents with the increase of radiation doses. The ratio of Potassium (K) and Calcium (Ca) contents change with respect to the refference sample (fresh & non-radiated) is presented in the table 4 respectively.

Effect of gamma radiation on Chromium (Cr) and Manganese (Mn)

Effect of gamma radiation on Chromium (Cr) and Manganese (Mn) contents in the samples is represented in the table 3 where each sample was duplicated.

The figure 4 shows that the concentration of Cr obtained from the samples, radiated with various doses (0.0, 0 1.0, 2.0, 2.5 & 3.0 kGy) is 112931, 82720, 42033, 63553, 19213 ppm. Whereas,  the figure 5 shows that the concentration of Mn is 8717, 4604, 3552, 4701, 2654 ppm. The values of Cr and Mn decrease with increase of radiation doses. (N.B.: Error greater than 30% is neglected)

So, the obtained results of the present study the effect of gamma radiation on essential mineral contents of Cucumber irradiated with different radiation doses shows a gradual decrease with the increase of radiation dose. The changes ratio of Chromium (Cr) and Manganese (Mn) contents in the samples with respect to the refference sample (fresh & non-radiated one) is presented in the figure 4 & 5 respectively.

Effect of gamma radiation on Iron (Fe) and Nickel (Ni)

Effect of gamma radiation on Iron (Fe) and Nickel (Ni) contents (ppm) in the sample is represented in the table 5 where each sample was duplicated.

Table : Conc. of Iron (Fe) and Nickel (Ni) contents (ppm) of control and radiated cucumber

(N.B.: Error greater than 30% is neglected)

The observation from the table 5 shows that the amount of Iron (Fe) concentration obtained from the samples, radiated with various doses (0.0, 0 1.0, 2.0, 2.5 & 3.0 kGy) is 358512, 224240, 109345, 156003, 4485 ppm. Whereas,  the amount of Nickel (Ni) is 29267, 15675, 7016, 10264, 186264 ppm. The values of Fe decrease with increase of radiation doses but increase in radiation of 2.5 kGy and the value of Ni decrease with increase of radiation doses but increase in radiation of 3 kGy.

So, the obtained results of the present study about the effect of gamma radiation on essential mineral contents of Cucumber irradiated with different radiation doses shows a gradual decrease with the increase of radiation doses. The changes ratio of Iron (Fe) and Nickel (Ni) contents in the samples with respect to the reference sample (fresh & non-radiated one) is presented in the Table 5.

Effect of gamma radiation on Cupper (Cu) and Zinc (Zn)

The results from Figure 6 & 7  show that the concentration value of Cupper (Cu) obtained from the samples, radiated with various doses (0.0, 0 1.0, 2.0, 2.5 & 3.0 kGy) is 2957, 1654, 607, 709 (ppm). Whereas, the amount of Zinc (Zn) concentration is  977, 1971, 2327, 3025, 3186 ppm. The values of Cu concentration decrease with increase of radiation doses and the values of Zn concentration increase with increase of radiation doses.

(N.B.: Error greater than 30% is neglected)

So, the obtained results of the present study about the effect of gamma radiation on essential mineral contents of Cucumber irradiated with different radiation doses shows a gradual decrease with the increase of radiation doses for Cu and gradual increase with increase of radiation doses . The changes ratio of Cupper (Cu) and Zinc (Zn) contents in the samples with respect to the reference sample (fresh & non-radiated one) is presented in the figure 6 & 7 respectively.

Actually it is observed that there no as much as significant radiation effect has been found on the concentration of essential minerals content into the radiated samples with respect to control sample since it is expressed in ppm unit.

There is no similar type of work on Cucumis sativus (Cucumber) by Tandem accelerator in Bangladesh. Though, a lot of works have been done on the nutritional assessment of  cucumber as well as the radiation effect on essential minerals contents of Cucumis sativus (Cucumber) by traditional methods but due to the Tandem accelerator facilities of Bangladesh Atomic Energy Commission (BAEC) it has become possible to complete this study. It has been tried to do this work fairly and accurately.

The present study shows that the evaluated essential mineral contents of fresh and non-radiated  Cucumis sativus (Cucumber)  is K 183699 ppm, Ca 70144ppm, Cr 112931ppm, Mn 8717 ppm, Fe358512ppm, Ni 29267 ppm, Cu 2957 ppm and Zn977ppm respectively which is comparable to the data of USDA Nutrient Database for Standard Refference (2004) for Cucumis sativus (Cucumber).

The present study was  carried out on the concentrations of constituent (major, minor and trace) elements present in Cucumber. In carrying out the analysis, the best and most convenient method being the Instrumental Neutron Activation Analysis (INAA) by tandem accelerator. Cucumbers were collect from local market, crushed to powdery form and samples prepared for INAA.The weight of the samples were 0.200g. The samples were fed in to the nuclear reactor by means of pneumatic transfer with the aid of rabbit capsules. The irradiated samples have been analysed and the following elements identified K, Ca, Cr, Mn, Fe, Ni, Cu, Zn. The purpose of this  study intends to a better understanding the effect of the essential element of cucumber by different doses (00KGy, 1KGy, 2KGy, 2.5KGy, 3KGy)  of gamma radiation. Before radiation Iron (Fe) is the major constituent of control sample comprise 358512 ppm. Potassium (K) is the 2^nd highest constituent of controlled sample of carrot whose amount 183699 ppm.  Chromium (Cr), Calsium (Ca) and Nickel (Ni) show moderate value of 112931ppm  70144 and 29267 ppm respectively. Whereas, amount of Manganese (Mn), Cupper (Cu) and Zinc (Zn) is very low only 8717 ppm,2957 ppm and 977 ppm respectively.

The results of these study, after radiation there are different effects are observed by different doses (00KGy 1KGy,2KGy, 2.5KGy, 3KGy)  of gamma radiaton on essential elements of cucumber. Both potassium (K) & Calcium (Ca) concentration is high (387421 ppm & 179910 ppm) for 2 KGy radiation. Cromium (Cr) & Magnesium (Mn) concentration is high (112931 ppm & 8717 ppm) for control (0KGy) radiation. The concentration is high of Iron (Fe) & Nickel (Ni) are (358512 ppm & 186264 ppm ) for control (0KGy) &3KGy.Other two minerals are Copper (Cu) & Zink (Zn) concentration is high (2957 ppm & 3186 ppm) respectively for control (0KGy) & 3KGy radiation.

We have found that, samples radiated with control or 0, 1, 2, 2.5, 3 kGy showed a very insignificant change for K and Ca concentration of cucumber. Gradually decrease the concentration of Cr, Mn and Fe with increase radiation except 2.5 KGy. Radiated with 2.0 kGy and 3.0 kGy showed a very significant change for Ni concentration of cucumber and the changes are found insignificant for all other doses; Radiated with control or 00kGy and 3.0kGy showed a very significant change for Cu concentration of cucumber and the changes are found insignificant for all other doses; samples radiated with 1.0KGy, 2.0 kGy, 2.5 kGy, 3.0 kGy showed gradual increase for Zn concentration of cucumber.

Our study revealed that the effect of gamma radiation on essential minerals content of Cucumis sativus (Cucumber) is negatively correlated but the changes are not statistically significant. The similar result has been found by Wheeler et al. (1990) who commented that, there were no changes in the levels of essential minerals content as well. In this study, it is observed that changes in essential minerals content of Cucumi sativus (cucumber) in the doses of 1.0 kGy, 2.0 kGy, 2.5 kGy and 3.0 kGy are not statistically significant. Ladaniya M.S. et al. (2003) found that, doses up to 1.5 kGy cause decrease of minerals content of ‘Daucus carota, Daucus sativus and Daucus aeutanti’ which has similarity with the present study findings. Beste C.E.1973 have found that essential minerals such as K, Ca, Cr, Mn, and Zn are present in vegetables and the effect of gamma radiation on essential minerals content of Cucumis sativus ( cucumber)  is not greatly significant. I observed that concentration of cucumber are rapidly changed by Gamma radiation and the effect of Gamma radiation on essential minerals of fresh-cut cucumber radiated with 0 & 1 kGy for K & Ca was significant. Cr, Mn, Fe, Cu & Zn was significant for 1KGy and Ni was significant for control & 1 KGy doses. Similarly observed other doses are non- significant.

However, the effect of gamma radiation is not same on even fruits and vegetables of same species. Some fruits and vegetables show great sensitivity to radiation, where some show very little. The present study has found that Cucumis sativus (Cucumber) shows high sensitivity to radiation treatment.

Summary and Conclusion

The essential mineral conc. of fresh and non-radiated (control) Cucumis Sativus (Cucumbers) were K 183699 ppm, Ca 70144 ppm, Cr 112931 ppm, Mn 8717 ppm, Fe358512ppm, Ni 29267 ppm, Cu 2957 ppm and Zn 977ppm. The effect of gamma radiation on the essential mineral contents of cucumbers were treated with radiation of doses 1.0 kGy, 2.0 kGy, 2.5 kGy, 3.0 kGy and one sample was kept controlled. All the samples were kept at -20⁰C temperature. The value of K content changes from 183699-302477 ppm for 1.o kGy, 183699-387421 ppm for 2.0 kGy, 183699-358772ppm for 2.5 kGy and183699-357418ppmm for 3KGy. The value of Ca changes from 70144-139367ppm for 1.0 kGy, 70144-179910 ppm for 2.0 kGy, 70144-178251 ppm for 2.5 kGy and 70144-169022 ppm for 3.0 kGy; value of Cr content changes from 112931-82720 ppm for 1.0 kGy, 112931-42033 ppm for 2.0 kGy, 112931-63553 ppm for 2.5 kGy and 112931-19213 ppm for 3.0 kGy; value of Mn content changes from 8717-4604ppm for 1.0 kGy, 8717-3552ppm for 2.0 kGy and 8717-4701 ppm for 2.5 kGy and 8717-2654ppm for KGy ;  value of Fe content changes from 358512-224240 ppm for 1.0 kGy, 358512-109345 ppm for 2.0 kGy, 358512-156003ppm for 2.5 kGy and 358512-44857ppm for 3.0 kGy; value of Ni content changes from 29267-15675ppm for 1.0 kGy, 29267-7016ppm for 2.0 kGy and 29267-10264 ppm for 2.5 KGy and 29267-186264 ppm for 3.0 kGy; value of Cu content changes from 2957-1654 ppm for 1.0 kGy, 2957-607 ppm for 2.0 kGy, 2957-709 ppm for 2.5 kGy and 2957-0ppm for 3.0 kGy; value of Zn content changes from 977-1971ppm for 1.0 kGy,977-2327ppm for 2KGy,977-3025ppm for 2.5KGy and 977-2327ppm for 3.0 kGy radiation doses respectively.

It is observed that, this decreasing rate of essential mineral contents of Cucumis Sativus (Cucumber) increases with increasing radiation doses that means the decreasing rate is directly proportional to the increasing rate of radiation doses except some doses due to the Tandem beam’s error. This decreasing rate is statistically significant. In this study it is observed that the essential mineral content of  Cucumis Sativus (Cucumber) is sensitive to irradiation doses. There are various effect are observed on the essential mineral contents of Cucumis Sativus (Cucumber) different (0, 1, 2 ,2.5, 3KGy)  of radiation doses.

So, it is concluded that, Cucumber is a rich source of some essential minerals those play vital roles for human body but these minerals are is sensitive to gamma radiation doses.

Cucumber is an important and beneficial fruit. The work on Cucumber is in still very initial stage. So further work with wide range of research in nutritive analysis preservation  varietal improvement etc. point of view need to be conducted to make it more familiar and popular to people by Tandem Accelerator or other processes..