ارزیابی مخمرهای جداشده از پساب‌های صنعتی جهت حذف سلنیوم و به‌کارگیری بیومس تولیدی در غذای دام و طیور

زمینه و هدف: جذب زیستی جایگزین مناسبی برای روش‌های فیزیکی و شیمیایی مرسوم برای حذف فلزات سمی از آب‌های زیرزمینی و پساب‌ها است. در این تحقیق، مطالعه فنوتیپی و ژنوتیپی به‌کارگیری مخمرهای جداشده از پساب‌های صنعتی باهدف حذف زیستی سلنیوم و به‌کارگیری بیومس تولیدی به عنوان غذای دام و طیور انجام شد. هدف نهایی ارزیابی مخمرهای جداشده از پساب‌های صنعتی جهت حذف سلنیوم و به‌کارگیری بیومس تولیدی در غذای دام و طیور است.روش کار: در مطالعه حاضر سویه های مخمری از پساب فاضلاب جداسازی شد و پس از تایید آن‌ها با استفاده از تکثیر ناحیه its و بررسی ارتباط تکاملی آن‌ها با سویه‌های s1 (کاندیدا آلبیکانس ng67) و s2 (کاندیدا آلبیکانس m48a) حذف سلنیومی انجام شد.یافته‌ها: بررسی توان این جدایه‌ها برای تحمل سلنیوم با استفاده از محیط کشت pyt agar حاوی غلظت‌های مختلف از 4 تا 15 mmol از se2+ انجام شد. سویه‌های دارای قابلیت سلنیوم کلنی‌های قرمزرنگ در محیط pyd آگار حاوی سلنیت بود. این سویه‌ها به عنوان سویه‌های برتر انتخاب شدند. در ادامه به منظور انتخاب بهترین سویه مخمری کارآمد برای انجام آزمایش‌ها سلنیت زدایی، آزمون mfc انجام شد.نتیجه‌گیری: الگوی مقاومت سویه‌های مخمری جداشده با توجه به mfc نشان داد که بیش‌ترین مقاومت به یون سمی سلنیت (تحمل‌پذیری بالاتر از 22 gr/l) مربوط به سویه s1 بود. پروتئین میکروبی تولیدشده در این تحقیق کاربرد فراوانی داشته و می‌توان از آن به عنوان یک ماده افزودنی و پروبیوتیک در جیره غذایی دام، طیور آبزیان استفاده نمود.

evaluation of yeast isolated from industrial waste to remove selenium and the use of biomass in livestock and poultry food

background & aims: bioavailability is a good alternative to conventional physical and chemical methods for removing toxic metals from groundwater and wastewater. selenium is a non-metallic substance. although large amounts of selenium are toxic، proper consumption is essential for specific cellular functions. in the seasons when there is a maximum spawning rate، due to the excretion of high levels of selenium through the eggs from the body، the balance of selenium in the body is disturbed and its amount is reduced to a minimum and the body becomes susceptible to virus attack. laying birds are more common (1، 2).reproduction of viruses، especially avian influenza، also requires selenium، which is higher due to the high proliferation of viruses، but the selenium required for a virus is very low، and if there is enough selenium in animals، the virus enters the body. in other words، the virus poisons itself with selenium، and this is a schematic example of the fight against toxins، as well as a way to fight and defend the type of prevention، not when the disease occurs. falls down. numerous microorganisms such as bacteria، yeasts، molds، algae and higher fungi that are grown on a large scale can be used as a rich source of protein for humans and animals. yeasts are among the organisms that are widely used to produce protozoan proteins، and the most important of them are saccharomyces، torulopsis، candida، didium، etc. (5).methods:  in this research، phenotypic and genotypic study was carried out on the use of isolated yeast from industrial effluents with the aim of eliminating selenium biological and the production of biomass as a feed for livestock and poultry. in the present study، yeast strains were isolated from wastewater and after confirmation by using the replication of the its region and their evolutional correlation with s1 strains (candida albicans ng67) and s2 (candida albicans m48a) selenium removal was performed. sequencing: to confirm the sequences obtained by pcr، the sequencing reaction was performed according to sanger method by gene fanavaran company. in this sequencing، the cycle sequencing kit big dye terminatorv3.1 from applied biosystems and the abi sequence analyzer 3130xl from the same company were used. the sequence of each dna strand was analyzed using the corresponding chromatogram and chromas (technelysium) software. the questionable bases were examined by careful examination of the chromatogram and comparison with the chromatogram of the reverse string sequence. chromas (technelysium) software was used to analyze and compare all genetic changes.results:  the ability of these isolates to tolerate selenium was performed using pyt agar medium containing different concentrations of 4-15 mm of se2 +. selenium-capable strains of reddish colonies contained selenite in pyd agar medium. these strains were selected as superior strains. enrichment and determination of selenium resistance pattern in yeast strains: after optimizing the reaction conditions of bilenium selenite removal reaction by single factor method and finding appropriate values of reaction parameters، the effect of heating time on removal efficiency was investigated. based on the results obtained after 72 hours of heating، the resting yeast cells were able to remove more than 93% of the selenium in the conversion medium، indicating the potential potential of the microbial catalyst to remove toxic selenium from the reaction medium.conclusion: the mfc test was conducted to select the best yeast strain for performing desulphurisation tests. the resistance pattern of isolated yeast strains according to mfc showed that the highest resistance to toxic selenite ions (tolerance greater than 22 g / l) was related to strain s1. the microbial protein produced in this study is widely used and can be used as an additive and probiotic in the diet of livestock، poultry، and aquatic animals.in the present study، yeast strains were isolated from wastewater and after confirmation، selenium removal was performed by replicating the its region and investigating their evolutionary relationship with strains s1 (candida albicans ng67) and s2 (candida albicans m48a). for this purpose، selenium-capable strains of red colonies in pyd agar medium contained selenite. these strains were selected as the top strains. then، in order to select the best efficient yeast strain for selenite removal experiments، mfc test was performed. resistance pattern of isolated yeast strains according to mfc showed that the highest resistance to toxic selenite ion (tolerance above 22 g / l) was related to s1 strain. these results are consistent with the study of ashnagarov et al. protozoan protein can be produced from various sources. researchers have conducted various studies on the production of protozoan proteins from substrates such as agricultural wastes (molasses، rice، citrus)، chemical by-products (methane and petroleum derivatives)، and fishery wastes (such as shrimp skin). each of the studies used different microbes or microbes and the conditions for preparing the growth medium of the microorganisms used were different. the results of studies by scholes et al. showed that the amount of crude protein in scp produced from yeasts was between 39-68%، while this amount in bacterial scp was about 82%. the amount of essential amino acids of yeast protein was between 6.4-6.4% per gram of protein. however، the amount of total fat in protein with different microbial origins has been variable. the results of the present study also confirm the above results.the results of a study by samuel et al. in 1992 showed that when using microbes، the average crude protein in fish and crab waste was 60.4% and 44.1%، respectively. ferrer et al. used shrimp shells to produce microbial protein and used marine yeast to achieve this goal. the results showed that the specific growth rate and crop production coefficient were 0.398 per hour and 447% kg dry cell weight، respectively. recently، due to the lack of protein، efforts have been made to discover alternative sources of common food and feed. scp is cheap for everyone and safe to eat. genetically modified، high-yielding non-toxic microbes can also be used to increase scp production. during a study، scientists coated medical lenses with selenium to prevent bacteria from growing and multiplying on the lenses (11).