Abstract
Vegetarian diet s were sampled in winter (19) and summer (16) and evaluated to determine the concentrations of nitrate, 13 phytoestrogens, two glycoalkaloids, 12 trace elements and 3 furanocoumarins. Hydrolysed and non-hydrolysed assessment techniques were applied in Phytoestrogens. The average total isoflavone levels in diets, exclusive of hydrolysis, were 15 mg kgÉ1_1 in winter and 14 mg kg_1 in summer, equivalent to generally hydrolysed aglycone levels of 10 mg kgÉ1. The concentration of tin element was found to be 4.6 mg kgÉ1 in winter and 2.2 mg kgÉ1 summer. The nitrate level was higher in summer than in winter with 51 mg kgÉ1 and 45 mg kgÉ1. The xanthotoxin, furanocoumarins psoralen and bergapten had mean concentration of 0.07545 mg kgÉ1. Finally the concentration of glycoalkaloid a-chaconine was 14 mg kgÉ1 in one sample with limit of detection of 0.8 mg kgÉ1. There was a negligible compositional concentration difference between winter and summer diets. For isoflavones an average aglycone corresponding ingestion of 10.5 mg per day was computed, where we had 5.5 and 2.2 mg per day intake for winter and summer respectively. Nitrate consumption was 53mg per day.. Except for an amplified tin ingestion during winter, vegetarians contact with individual natural toxicants, phytoestrogens and inorganic trace-elements was similar to that of the common residents. All the concentration was below the required consumption concentration levels.
Introduction
According to up to date report on consumer eating habits in the UK, we see that 1% consist of Vegan, 5% of the public do not consume meat or fish and 7% are vegetarian person. While in USA we have approximately 26 million Soya consumers. Due to lacto-vegetarian dietary habits, there have been concerns about there contact with pollutants, nutrients and non-nutrients from foods as compared to other consumers which may lead to variety types of health risks. Vegans possibly have lesser dietary contact with matters which are more common in fish or meat. On the other hand they may perhaps have above average the portion of vegetables content and consequently have elevated levels dietary exposure to vegetable constituents. Furanocoumarins, glycoalkaloids, and phytoestrogens are some of Phytochemicals found in plants.
These Phytochemicals have advantageous properties particularly on cancer, coronary heart disease and hormone-related conditions. Phytoestrogens are not poisonous in human beings, although can lead to fertility disorders, particularly in sheep where extended contact results into permanent infertility. Moreover Phytoestrogens are non-essential nutrients since lacks of them in individuals diet do not cause any specific deficiency syndrome and they do not contribute to any important biological functions. Phytoestrogens demonstrates health enhancements characteristic at most favorable dietary concentration therefore is a non-nutrient health catalyst agent. Currently there is no daily set standards i.e. tolerable daily intake (TDI) or recommended daily intake (RDI) because there are out of scope to be categorized as essential nutrients, natural toxicants or pollutants (MAFF, 1998, p. 37).
In the UK, phytoestrogens are chiefly consumed in the form of daidzein, glycitein, and isoflavones genistein found in Soya and additional legumes principally as glucoside conjugates, hence increase in Soya intake in recent times. The bulk of fresh bakery foods, especially conventional family bread loaf, have Soya flour, which makes sure lasting freshness is maintained. Legumes are recurring vegetables, even though these can easily be frozen or dried during the year as Soya source as can Soya containing products. In 1999, the US FDA accepted a health allegation on the correlation between Soya protein consumption and decreased dangers o f coronary heart disease attacks as being associated with low fat diet. These may have resulted to continuous increase in quantity Soya intake both in Europe and the USA (MAFF, 1998, p. 38).
Nitrate occurs naturally in drinking water and some foods and this possibly due fertilizer use and food additives. This chemical compound is of concern due to its valuable and harmful health effects. On the dark side of nitrates, we have possible carcinogenic N-nitrosamines and in situ teratogen. Furthermore when this nitrate is reduced to nitrite it then is oxidizes Fe2+ ion in the oxyhaemoglobin to the Fe3+ oxidation state causing blue baby syndrome and methaemoglobinaenia.On the contrary, under stomach acidic conditions it causes nitric oxide formation which is linked to protection against pathogenic microorganisms. Due to human activities, trace elements and metals such as arsenic, cadmium, tin which are harmful to human beings exist in food. I further elements for example zinc, selenium and copper are vital for health but dangerous at higher levels of concentration.
Prolonged exposure to these elements is risk for example organic mercury compounds are neurotoxins, high concentrations of tin in food causes stomach disorders and consumption of lead is dangerous to neuropsychological development. Cadmium and mercury negatively have affect on renal function while inorganic arsenic is cancer causing agent. Arsenic and mercury concentration are higher in fish than in other foods while those nuts found in Brazil have selenium. Based on this data we predict that vegans have greater selenium and aluminium concentration and lesser mercury and arsenic ingestion. The a-chaconine and glycoalkaloids a-solanine are available in Solanum species for example potatoes and levels of these chemical greater than 200 mg kg_1 in potatoes are toxic. Furanocoumarins for instance, xanthotoxin, psoralen and bergapten are contained in vegetables, citrus fruit and levels of 30 mg kg_1 are taken as normal. We draw conclusion than lacto- vegetarians are projected to have consumption of essential and risk food constituents that vary from universal population of omnivores. The objective of this research was to make available first hand data on dietary consumption of inorganic trace elements, glycoalkaloids, phytoestrogens, nitrate and furanocoumarins for vegans in UK during winter and summer seasons (Clarke et al, 2002, p. 153).
Materials and methods
Sample collection
First there was recruitment of 400 vegans who had participated in past dietary research. Only non-smoker and non-consumer of meat/fish participated. Participants were to eat alternative protein for example, textured vegetable protein tofu etc. Participants gathered an accurate copy of every solid foodstuff consumed in 1-week duration. Soya milk; soup and herbal tea were sampled as they have phytoestrogens. Any dietary supplements and medicines used by participants were recorded in a food diary which was supervised to make sure subjects upholded a lacto-vegetarian diet. There was regular evaluation and tabulation of subjects weights and health status and confirmatory visits on second day of data collection to make sure dietary compliance the sum mass of the gathered was weighed against the log record as a concluding check. We had sample collection during summer period (26 August to 1 September 1997) and winter season (915 February 1998). Sample diets were kept in freezers and refrigerators before being conveyed to the IFR laboratory (Institute of Food Research, UK) for laboratory analysis. Data collected by British Market Research Bureau International Limited, UK which is a Food Standards Agency (Clarke et al, 2002, p. 153).
Sample treatment and storage
Every duplicate vegan diets were measured and normalized by a food processor after that, diets were subdivided for examination. Homogenization of diets sample was enhanced by adding water. A fraction of furanocoumarin analysis, phytoestrogen, elemental and glycoalkaloids analysis were dried by freezing method. Then all fractions kept at 18 _C awaiting analysis (Clarke et al, 2002, p. 153).
Dietary assessment
To be able to establish if the diets stood for typical food consumption, the mean every day energy intake (EI) was approximated via application of the Comp-Eat 5 computer programme (Nutrition Systems, London, UK) by the South Bank University, London under a FSA contract. The basal metabolic rate (BMR) was approximated from regular equations integrating age, gender and weight operators. Where achievable, the values gotten were then weighed against compositional values for the mean UK diet and acceptable safe exposure concentrations. When computing every days consumption values a figure corresponding to the limit of detection for diets was applied. The study assumed 60kg bodyweight (Clarke et al, 2002, p. 153).
Phytoestrogen analysis
Extraction
Isotope dilution LC-MS method of analysis was used where the Phytoestrogens gauged without and with acid hydrolysis. 0.5 g of the sample was extracted using aqueous methanol (5.0 ml, 80%) at 60 _C for a period of 1 hour under constant stirring. followed by centrifugation of 8000 g sample for 5 min and then air passed through the supernatant and final repetition of extraction process. The extracts were washed with hexane (4 x10 ml) and the residue dissolved in 5ml of 50% aqueous methanol and then a half of this product underwent hydrolysis. The remaining portion was evaluated directly after filtration. Hydrolysis was performed as follows: Hydrolyzed isoflavone aglycones was extracted into 3×5 ml of ether and dried, liquefied in 5ml of 50%aqueous methanol and filtered with 0.45 µm filter paper before analysis (Clarke et al, 2002, p. 155).
Results and discussion
Dietary assessment
Duplicate diet research studies should give a direct description of the utilization and total dietary contact of persons to contaminants and food components. Subjects were directed to collects same fractions of every foodstuff they consume for analysis. Thirty-five 7-day vegan duplicate diets were examined. 7.83 kg mean diet stands for a food solids ingestion of 1.12 kg day_1. The standard body mass Of 69.2 kg scrutinized in this research study is 15% greater than the 60 kg standard presumed when accounting UK ingestion figures. The greater part of subjects guzzled bigger amount of cereal-based foodstuff items, instead of eating a bigger percentage of vegetables or vegetable protein alternatives and fresh fruit as projected by general publics point of view off vegetarianism (Argonne National Laboratory 2005).
Phytoestrogens
Isoflavones were observed in 31 out of 35 diets. Out of twelve, ten of person genistein, gluco-conjugates, glycitein and daidzeinaglycones supposed from Soya foods were seen in the diets (Table 2).The small phytoestrogens; biochanin A coumestrol and formononetin were observed in any diet test samples neither before nor after hydrolysis. The isoflavone composition of diets was equal to 43 mg kg_1 of genistein, 21 mg kg_1 of daidzein, and 3 mg kg_1 of glycitein correspondents (MAFF, 1998, p. 38).
The mean levels were: 3.1 mg kg_1 of daidzein, 0.6 mg kg_1 of glycitein and 6.1 mg kg_1 of genistein equivalents. The average combined aglycone daily intake figure was 10.5 mg day_1 (Table 3). We note negligible differences in the consumption of whichever of the aglycone equivalents, 12 entity isoflavones and entire isoflavones between winter and summer diets. Parent aglycone plus three glucose conjugates matched with the sum measured hydrolyzed daidzein level concentration. Conformity between the total hydrolyzed genistein and genistein equivalent concentration total concentration differed as a few hydrolyzed samples were detected to have noteworthy more genistein than expected. The allocation of genistein gluco-conjugates, for instance a hydrolysable genistein constituent that is not acetylgenistin genistin, or malonylgenistin and an lack of glycitein, daidzein, and their conjugates indicates a greater concentration non-Soya supply of genistein. Mass spectral research on such diets samples showed extra non-soya genistein conjugates for example genistein- 40-glucoside (sophoricoside) (Walker, 1990, p. 153).
The average conjugation outline was ; malonylglucose-conjugates 21%, acetylglucose-conjugates 5% , glucose- conjugates 61% and aglycones 13% with mean ratio27:3:62:6 in winter and 15:5:62:18 in summer diets. These outlines need to be observed against the development detected in primary soya products, in which conjugation ratios of 6:77:2:15 for Soya milk ,1:52:9:38 for full fat soya flour, and 26:41:22:11 for a textured soya protein food were evaluated to help out in conjugation pattern identification. Results also indicates that a noteworthy fraction of the isoflavone composition of vegan diets may be from greatly processed second generation soya foods, in which key soya products for example soya milk ,soya flour, and textured vegetable protein are employed as components in complex foods that are put through further processing. The leading decile of the lacto-vegetarian diets in this research were as good as in isoflavone composition to the mean Asian diet. We have approximated the mean UK ingestion of the daidzein, glycitein, isoflavones genistein, as 3mg per day (Walker, 1990, p. 164).
Metals
Individual metal concentration is shown in table 5. we look at individual metal concentration
Aluminium
The mean aluminium dietary ingestion was 3.3 mg per day and is analogous to the contact of the mean UK population, 3.4 mg per day. We see 11 mg per day concentration in diet as the greatest and was inside the 60 mg per day
Arsenic
For this element we had ingestion 0.018 mg per day dietary and is less than the 0.065 mg per day consumption of the average consumer. Again food with highest concentration of 0.089 mg per day falls within 0.12 mg per day limit. This maximum value is for the more poisonous inorganic arsenic element, and greater part of the arsenic traces in food is occurs in less lethal organic forms. Note total arsenic concentration has been recorded since it is not easy to distinguish it analytically. Main arsenic source is fish and lack of it in these diets explains low figure for its concentration.
Cadmium
The food with the highest concentrations gave 0.025 mg per day which falls within acceptable levels limit of 0.06 mg day Cadmium concentration is present at small levels in most foods in especially potatoes and bread
Chromium
The mean chromium dietary ingestion was 0.11 mg per day and comparable to that of the typical consumer with.10 mg per day. The highest concentration diet showed an ingestion of 0.26 mg per day. No set limit or standard for chromium but 0.025 mg per day is advisable and no concern over its toxicity.
Cobalt
The average cobalt dietary ingestion was 0.011 mg per day and is same as that of the mean UK population with 0.012 mg per day. The diet with the greatest concentrations gave an ingestion of 0.025 mg per day. An ingestion of 0.0015 mg per day for is advised. The concentrations in the vegan diets are same as those of the previous research and also no worry as far as deficiency or toxicity is concerned.
Copper
The mean copper dietary consumption was 1.4 mg per day, comparable to that of the average consumer with 1.2 mg per day.Highly concentrated diet gave an contact of 2.7 mg per day. Copper is an necessary nutrient that can be poisonous at high concentrations. We have a limit of 30 mg per day intake and no diets surpassed the maximum limit.
Lead
The average lead dietary consumption indicated 0.016 mg per day less than one average consumer, 0.026 mg per day. The highest concentration was 0.07 mg per day compared to days limit of21 mg per day. Drinking water and some beverages were major contributors. Recommend minimum exposure.
Mercury
The element was not detected.
Nickel
The mean nickel dietary ingestion was 0.18 mg per day and is alike with average consumer of 0.13 mg per day. Exposure to nickel can leads dermatitis in some person but no toxicity worries in general.
Selenium
The average consumption was 0.029 mg while average consumer was 0.039 mg per day and highest with is 0.050 mg per day. All diets are less than the maximum Contact of 0.45 mg per day. Selenium is a vital trace element and common found in great concentrations in nuts, offal and fish. Meat products, bread and fish contribute to a great deal of selenium in vegans (Zanders et al, 1999, p. 45).
Tin
The mean tin dietary ingestion was 3.9 mg per day and greater than that of average consumers with 1.8 mg per day. The diet with the greatest concentration of 16 mg per day less than highest recommended contact with higher being in winter.
Zinc
For zinc element we had ingestion was 7.87 mg per day as the highest comparable to 8.4 mg per day for average consumer. The highest gave 17.7mg per day and 60 mg per day contact is allowed. In general the concentration of these elements was harmless to vegans.
Glycoalkaloids and furanocoumarins
Glycoalkaloids were observed in only one diet, where a-chaconine was indicated 14 mg per kg in 12 diets. Potatoes in general contain a higher concentration of a-chaconine as compared to a-solanine concentration and complies with dietary record which registered the intake of 3 baked potatoes which had up to 50 mg per kg of a-chaconine. a-solanine was not present in other diets. Alkaloids are common concentrated on the skin of potato. Furanocoumarins were present in 15 out of 35 diets as shown in table 8. Finally xanthotoxin, psoralen, and bergapten combined level was same in winter and summer diets with average levels of 75mg per kg (Walker, 1990, p. 164).
Nitrates
Nitrate
The average nitrate level was found out to be s 48 mg per kg in diets The periodical nitrate levels were 51mg per kg summer and 45 mg per kg winter. Nitrate levels in vegetables are well-known to show Seasonal fluctuations. Low concentrations were indicated in spinach, carrot, lettuce, potatoes, onions and cauliflower planted in the UK in the summer period in contrast to those planted during winter. Leafy vegetable plants planted winter in greenhouses devoid of artificial light showed highest nitrate concentrations hence increased contact in winter seasons
Conclusion
Apart from tin, there were no noteworthy dissimilarity winter and summer dietary ingestion values and all individual vegan diet samples went beyond recommended toxicological limits. Ingestion of isoflavones was less in contrast to Asian diet but thrice greater than the mean UK consumers. Dietary ingestion of nitrogen dioxide for lacto-vegetarian is same as other users and well below limit. Vegan intakes of cadmium, aluminium, cobalt, chromium, copper, zinc and nickel is same to those other UK general population. Selenium, Lead, and arsenic dietary contact are less and tin concentration double for vegans as compared to the general population. All diet indicated low concentration of furanocoumarin or glycoalkaloid natural toxicants.
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