Nine lactating buffaloes were ranked into three groups (three animals each) using 3x3 Latin square design (with 35 days each period). Experimental rations were: control (concentrate feed mixture (CFM): berseem clover (BC), 2:1 DM basis), low selenized yeast [control ration plus10 g/h/d selenized yeast (2.5 mg Se/h/d)] and high selenized yeast [control ration plus10 g/h/d selenized yeast (4.5 mg Se/h/d)]. At the last 3 days of each period, the collected milk from each group was pooled and used for analysis and manufacturing of Domiati cheese. The obtained results indicated that feeding diets supplemented with low or high selenized yeast improved milk yield and its protein content significantly (p<0.05). Also, both yield and protein recovery of cheese from group fed diet supplemented with low selenized yeast was improved as compared with high selenized yeast and control diets. Feeding diets supplemented with low or high selenized yeast had no effect on chemical, physical and organoleptic properties of Domiati cheese. The increase in total protein, fat and firmness of cheese during storage was correlated with decrease in pH values and moisture content of cheese. Also, the weight loss of cheese was more correlated with increase in soluble nitrogen and decrease of moisture content of cheese.
Three sample preparation methods - proteolysis to determine the initial species distribution, and an in vitro gastric and gastrointestinal digestion to assess the bioavailability of selenium - were applied to extract the selenium from selenized green onion and chive samples. Ion exchange chromatography was coupled to a high-performance liquid chromatography-ICP-MS system to analyze the selenium species of Allium samples. The difference in the selenium accumulation capability of green onions and chives was significant. Chive accumulated a one order of magnitude higher amount of selenium than did green onion. After proteolysis of both types of Allium plants, high amounts of organic selenium species such as MeSeCys, SeCys2 and SeMet became accessible. In the case of Se(VI)-enrichment, selenate was the main species in the proteolytic extract. After simulating the human digestion, the organic species were just slightly bioavailable compared with the results from proteolysis. The inorganic selenium content of the selenized samples increased significantly and SeOMet could be detected from the extracts. As an effect of the significant pH change between the gastric and the intestinal tracts, two oxidation processes took place: selenite oxidized to selenate, while SeMet oxidized to SeOMet.
Bread is a most important food product and source of selenium in Ukraine. However, low content of selenium in wheat flour from north and northwest regions of Ukraine does not ensure the recommended consumption of selenium. Daily intake of selenium by the population of North Ukraine is below recommended allowance. The aim of this research was to study the production of the dietary rolls with selenium-enriched yeast for the population of North Ukraine. The study showed that to obtain bakery yeast of good quality, concentration of sodium hydroselenite in the medium for yeast cultivation should be in the range from 2 to 5 μg Se/ml. Under these concentrations of selenium in medium, specific growth rate and biomass yield as well as bakery properties of the yeast Saccharomyces cerevisiae did not differ from the parameters of yeast, grown in the medium without selenium. Maturation of the selenium-enriched yeast improved their bakery properties. The 100 g wheat roll prepared with selenium-enriched yeast contained 50 μg Se (25% of the recommended daily allowance) in the form of selenomethionine, which is the best form of selenium for human consumption. These rolls can be used as a dietary product to reach recommended daily consumption of selenium by the population of North Ukraine and Chernobyl region.
This paper describes a simple/low volume enzymatic extraction method for selenomethionine (SeMet) determination in selenized yeast samples. In contrast to traditional methods which generally utilize large sample volumes consuming significant amounts of costly enzymes, the modified protocol employs a microtiter plate format allowing a reduction of the required sample volumes to 1 mL per extract. The extraction is performed in a parallel (5 × 4 = 20 position microtiter plate) reaction platform made out of sintered silicon carbide, fitted with standard disposable glass HPLC/GC vials. Due to the high thermal conductivity of silicon carbide, this set-up can be placed on a standard hotplate to accurately maintain the desired extraction conditions (37 °C, 20 h) for all positions of the microtiter plate. Hydrolysis of selenium-enriched yeast with a combination of protease XIV and lipase VII (ratio 2 : 1, w/w) using these low-volume conditions provided identical results to the more traditional high-volume method. The amount of SeMet was determined by HPLC/ICPMS and confirmed a high recovery rate for SeMet (93 ± 2%, n = 3) for the certified reference material SELM-1.
In the last years, functional foods have awakened consumer, scientific and business interest. A commonly found vegetable in such kind of foods includes garlic (Allium sativum). By its ability for selenium (Se) bio-accumulation, garlic can turn into an attractive option of selenized food. Selenium is an essential micronutrient for many organisms including plants, animals, and humans. It is an important trace element due to its antioxidant properties and plays a main role in prevention of cancer and cardiovascular diseases. Nowadays, there is an increasing interest in the study of Se speciation due to the different roles that each species manifests in toxicological and nutrition fields. However, Se exhibits a narrow interval between toxicity and essentiality, which is puzzling toxicologists and alarming nutritionists and legislators. In the present review, an overview on the development of selenized garlic studies and its potential implementation in Argentine production is exposed. The development of novel foods with added value such us selenized garlic could be an attractive alternative for local market. Moreover, it becomes a good offering for factory owners, considering that Mendoza represents about 85% of total garlic production in the country.
Selenium (Se) is considered as an essential element for human body. Selenized probiotic fermented milk drink (DOOGH) as a functional beverage to increase Se available in body. The predominate sugar, protein and mineral ion of Iranian yoghurt drink (DOOGH) are lactose, casein and calcium, respectively. Different levels of Selenium (2.5 – 3- 3,5- 4 and 4.5) is prepared and its suitability based on the sensory attributes and survival of starter and probiotic microorganisms in the presence of Se are evaluated. Result showed that the concentration sensory features (color, odor and flavor) of Se-enriched DOOGH were not affected at Se concentration levels below 5 mg L-1 for 4 weeks. The colony forming units (cfu) of Streptococcus thermophilus (starter bacteria) and strains Lactobacillus acidophilus and Lactobacillus casei (probiotic bacteria) of the Se-enriched DOOGH with different concentrations of Se and control sample (without Se) decreased during 4 weeks. There was significant (p<0.05) decrease in cfu of all bacterias after week 3. Population of microorganisms significantly (p<0.05) decreased at higher concentrations of Se (4 and 4.5 mgL-1).
Background: The trace element selenium (Se) is essential nutrition mineral. Selenium deficiencies in the human and animal organism are recognized worldwide to be related to a number of pathologies. However, at higher Se concentrations, harmful consequences occur: generation of free radicals, DNA double-strand breaks, and apoptosis in cells. Provided that the recommended dietary intakes are not met, Se-rich foods are to be included in the diet. Limitation of Se Studies: The disparate opinions on the widely discussed chemopreventive capability of selenium have to be addressed. Of paramount importance is a better understanding of the Se significance to the DNA preservation and cancer. The contradictions found might be related to poor understanding of controversial mechanisms involved in selenium biochemistry. Therefore, a rich area of selenium explorations could be considered as two fields: Se as a dietary component and Se as a toxic agent. Selenized Fungi: Mushrooms and yeasts have attracted a number of researchers in food and pharmaceuticals. Mushroom-based foods enriched with selenocompounds could be a convenient source of Se to balance the deficiency. Therewith the safety and efficacy factors favor the organic forms of Se. Conclusion: The consequences of selenium toxicity, bioavailability of selenium content, the importance and possibilities for increasing selenium content of mushroom mycelia, a fate of organoselenium xenobiotics in the basidiomycetes culture are discussed in this review.
A functional food is any food that has (a) specific nutrient(s) added to it for a specific functional purpose. Selenium (Se) is a metalloid that belongs to group 16 of the periodic table. It may be obtained from myriad sources like soil, water, and living organisms. Se is required to sustain proper health in both animals and humans due to its linkage with various biological functions in the immune system. Nature has made it impossible for us to obtain sufficient Se from the diet since some regions across the globe have been designated as Se-deficient while others are becoming Se-toxic. Se deficiency is associated with a compromised immune system and increased susceptibility to various diseases. Therefore, designing Se functional foods and supplements is the way forward in curbing the menace mentioned above, since geographical location will not have any effect on the Se content of these foods. Brewing yeast has the necessary enzymes to biotransform inorganic Se (Na2SeO3) to its bioactive organic form, which is incorporated in the aged selenized beer. S. cerevisiae was found to have better biotransformation efficiency than other yeast species. A traditional Slavic beverage, selenized kvass, was brewed using rye grains soaked and germinated in solutions of Na2SeO3. Fruit yeasts (Lesaffre) and Evitalia were utilized as the starter cultures. A Se enriched solution was extracted from Se-biofortified pak-choi cabbage and incorporated into the wort before fermentation. Selenized yeast and algae can be taken as supplements or as food additives. There have been some reports about microcystins (MCs) in Spirulina. Therefore, the safety of Se-algae is not guaranteed. Pasteurized dried selenized supplements (yeast and algae) were proposed in formulating Selenized enriched Tom-brown. This review seeks to propose some possible foods that could be enriched with Se. A large portion of the population adequately consumes these proposed foods on a regular basis hence the target goal would be a success.
Selenium (Se), which is present as SeCys in seleno-proteins, is involved in cancer prevention, thyroid functioning, and pathogen inhibition. Se is incorporated in the diet through Se-containing foods. Some lactic acid bacteria (LAB) can biotransform selenite (toxic) into Se-nanoparticles (SeNPs) and Se-amino acids. To exert their beneficial properties in the host, bacteria should survive the harsh conditions of the gastrointestinal tract and during food storage. We evaluated whether selenization of LAB influenced bacterial growth and survival during gastrointestinal digestion and after storage when present in a fermented fruit juice-milk (FJM) beverage. Lactobacillus brevis CRL 2051 and Fructobacillus tropaeoli CRL 2034 were grown in MRS with and without selenite, and used to inoculate the FJM matrix. Selenization had no effect on LAB growth (9.54–9.9 log CFU/mL) in the FJM drink. The presence of SeNPs was confirmed for both selenized strains in the FJM beverage; however, the highest Se concentration (100 μg/L) was detected for the fermented beverage with selenized L. brevis. Under storage conditions 1.1 log CFU/ml decrease in cell count of selenized cells of L. brevis was observed, while no effect on cell viability was detected for non-selenized L. brevis or both selenized and control cells of F. tropaeoli. Resistance of L. brevis during digestion of the fermented FJM beverage was not affected by selenization. Contrarily, an increase (1 log CFU/mL) in the resistance of F. tropaeoli was observed when cells were selenized. After digestion, Se was detected in the soluble fraction of the beverage fermented by both strains, being higher for L. brevis (23.6 μg/L). Although selenization did not exert a drastic effect on strains´ survival during storage and digestion, microbial selenization previous to food fermentation could be an interesting tool for Se enrichment avoiding thus the addition of toxic Se salts.
Selenium (Se) is an indispensable microelement in our diet and health issues resulting from deficiencies are well documented. Se-containing food supplements are available on the market including Se-enriched Chlorella vulgaris (Se-Chlorella) which accumulates Se in the form of Se-amino acids (Se-AAs). Despite its popular uses, data about the bioaccessibility of Se-AAs from Se-Chlorella are completely missing. In the present study, gastrointestinal digestion times were optimized and the in vitro bioaccessibility of Se-AAs in Se-Chlorella, Se-yeast, a commercially available Se-enriched food supplement (Se-supplement) and Se rich foods (Se-foods) were compared. Higher bioaccessibility was found in Se-Chlorella (∼49%) as compared to Se-yeast (∼21%), Se-supplement (∼32%) and Se-foods. The methods used in production of Se-Chlorella biomass were also investigated. We found that disintegration increased bioaccessibility whereas the drying process had no effect. Similarly, temperature treatment by microwave oven also increased bioaccessibility whereas boiling water did not.
The element selenium (Se) acts as a double-edged sword for humans and animals by being a nutrient at trace level and a toxin at elevated concentrations. It is needed for the biosynthesis of selenoenzymes and selenoproteins which mediate an array of activities such as antioxidant defense, detoxification, immunomodulation, carcinogenesis prevention, thyroid functioning, and sperm motility and maturation. Because of their culinary, nutritional, and health benefits, the demand for mushroom cultivation is increasing in India. The mushrooms are enriched with proteins, phenolics, antioxidants, vitamins, and microelements. Most of the edible and cultivated mushrooms show an array of biological properties. However, they are Se deficient, and it mandates the cultivation of Se-fortified edible mushrooms. Aim of work This review focuses on Se forms, distribution, dietary importance, mushroom cultivation, need of Se-enriched mushrooms, enrichment methods, nutritional and antioxidant significance, and anticancer activity of Se-biofortified mushrooms. Methodology and results Se-enriched mushrooms are produced by cultivation on substrates enriched with either inorganic or organic forms of Se and Se-hyperaccumulated agricultural residues. Edible mushrooms accumulate Se from substrate into selenoproteins and selenoenzymes as selenomethionine and selenocysteine, the organic and most bioavailable forms of Se. Without affecting the biological efficiency, the enrichment process enhances the total protein and total phenolic content and bioaccessibility of trace elements. The antioxidant action was higher for Se-fortified mushrooms in terms of total phenolics, total antioxidant, 1, 1-diphenyl-dipicrylhydrazyl (DPPH) scavenging, metal chelating, and lipid peroxidation inhibition activities in comparison with unfortified mushrooms. Also, Se-enriched mushrooms are known to retard chemically induced mammary tumors and proliferation of lung cancer cell lines. Conclusions Se-biofortified mushrooms act as potential functional food, nutraceutical, and diet supplements. Dietary intake of Se-fortified mushrooms aids in treatment and prevention of various conditions such as HIV infection, cancer, aging, cardiovascular, neurodegenerative and immunological diseases. The cultivation of Se-enriched mushrooms leads to sustainable empowerment of marginal, landless farmers; rural women; unemployed youth; and self-help groups. However, the technology development for Se enrichment is needed for commercial scale production. Other studies on volatile Se compound release during cultivation, safe disposal of spent compost, and Se leaching into ground water are warranted. The impact of cooking and traditional preservation methods on Se availability from mushroom meal to humans has to be evaluated.
Part One by Jeffrey Dach MD Selenium is an essential trace mineral critical for antioxidant defense, fertility, thyroid hormone metabolism, immune response, and muscle development. First discovered in 1817, selenium was considered a toxic substance best avoided. 140 years later, in 1957, the status of Selenium dramatically changed with a report of the first selenium deficiency disease. An obscure biochemist at the NIH, Klaus Schwarz, found that Vitamin E deficient rats were protected from liver degeneration by selenium.(1)
SELENIZED BAKERY PRODUCTS WITH CHEMOPREVENTIVE POTENTIAL A method for obtaining high-value bakery products.
