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Ethnic Indian people have been domesticating beneficial microorganisms (bacteria, yeasts, and moulds) by their wisdom of ethno-microbiological knowledge for production of flavoured and socio-culturally preferred fermented foods and alcoholic beverages for more than 8000 years. The purpose of this review is to collate the available literatures of diversity of Saccharomyces and non-Saccharomyces species associated with Indian fermented foods and alcoholic beverages. A colossal diversity of enzyme- and alcohol-producing yeasts under the phylum Ascomycota has been reported from Indian fermented foods and alcoholic beverages. The distributions of yeast species show 13.5% of Saccharomyces cerevisiae and 86.5% of some non-Saccharomyces spp. in Indian fermented foods and alcoholic beverages, based on the reported literatures available till date. There is a research gap on prospect of yeasts research in India. Hence, we suggest that validation of traditional knowledge of domestication of functional yeasts needs to be studied to develop the functional genomics platforms for Saccharomyces and non-Saccharomyces spp. in Indian fermented foods and alcoholic beverages. The purpose of this review is to collate the available literatures of diversity of Saccharomyces and non-Saccharomyces spp. in Indian fermented foods and alcoholic beverages. [ABSTRACT FROM AUTHOR]

Dahi and chhurpi are the homemade, mildly acidic and mouthfeel fermented dairy products of Sikkim in India. Since yeasts co-exist among traditional fermented dairy foods, we believe that some species of yeasts may have some probiotic properties. Hence, the present study is aimed at screening some probiotic yeasts from dahi and chhurpi. A total of 3438 yeasts were isolated from 40 samples of dahi (1779 isolates) and 40 chhurpi (1659 isolates) and were preliminarily screened for probiotic properties on the basis of survival in low pH, resistance to bile salts and the percentage of hydrophobicity, out of which only 20 yeasts were selected for in vitro and genetic screening of probiotic properties. Saccharomyces cerevisiae DJT-2 and Debaryomyces prosopidis CPA-55 showed the highest hydrophobicity of 97.54% and 98.33%, respectively. S. cerevisiae DRC-42 and S. cerevisiae CGI-29 showed 93.88% and 91.69% auto-aggregation, respectively. All yeasts showed co-aggregation properties against pathogenic bacteria. Kluyveromyces marxianus DPA-41 and Pichia kudriavzevii CNT-3 showed excellent deconjugation activities. Probiotic genes for acid tolerance, bile tolerance, adhesion and antimicrobial activity were detected in S. cerevisiae DAO-17, K. marxianus DPA-41, S. cerevisiae CKL-10 and P. kudriavzevii CNT-3. Based on the results of in vitro and genetic screening of probiotic yeasts strains, S. cerevisiae DAO-17 (dahi), S. cerevisiae CKL-10 (chhurpi), P. kudriavzevii CNT-3 (chhurpi) and K. marxianus DPA-41(dahi) were selected as the potential probiotic yeasts. [ABSTRACT FROM AUTHOR]

The extracellular enzymes produced by yeasts present in mangrove sediments were found to have wide range of biotechnological and industrial applications. Large scale production of these enzymes by bioprocess techniques needs proper optimization of culture conditions for high enzyme yield in a cost-effective manner. In the present study, we investigated the effect of different growth conditions like pH, salinity, substrate concentration and temperature on the growth and production of enzymes protease, amylase, lipase and ligninase by selected strains of Candida tropicalis. The optimum conditions for the maximum growth and enzyme production for protease, amylase, lipase and ligninase producing strains were found to be at pH 8.5-9; salinity 5-10 ppt and temperature 35 – 40°C with 2% casein, 1% starch, 1% tributyrin, 0.5% tannic acid as substrate concentrations respectively. The results suggest the use of yeast C. tropicalis from mangrove sediments as potent and promising strain for the large-scale production of hydrolytic enzymes when compared to the previous studies done on marine counter parts. [ABSTRACT FROM AUTHOR]

Heavy metals act as cofactors for several microbial enzymes and are required in low concentrations for the proper biological functioning of yeasts. Because concentrations beyond the permitted threshold can damage a cell's functionality and viability, metal tolerance in yeasts towards such heavy metals is therefore desirable during fermentation. Tyrosol, a quorum-sensing molecule in yeasts, protects yeasts from oxidative stress induced by various factors, but the performance of the molecule under heavy metal-induced stress is not known. In this investigation, the metal tolerance of four species of endemic yeasts from northeast India, Wickerhamomyces anomalus , Candida tropicalis , Saccharomyces cerevisiae and Candida glabrata , isolated from traditional starter culture cakes, was tested towards zinc (Zn+2), manganese (Mn+2), cobalt (Co+2) and copper (Cu+2) in the presence and absence of tyrosols retrieved from these isolates. The decreasing order of the tolerance of isolates was found to be Mn+2 > Zn+2 > Co+2 > Cu+2. Under the influence of tyrosols, isolates showed enhanced growth at their upper metal tolerance limit. Candida tropicalis showed enhanced growth (2−48-fold, P  < 0.0001) in all the tested metal consisting medium (2 mM Zn+2, 5 mM Mn+2, 2 mM Co+2 and 1 mM Cu+2), while W. anomalu s, C. glabrata and S. cerevisiae showed increased growth (3−17-fold, P  < 0.0001) in Zn+2 (2 mM), Mn+2 (5 mM) and Cu+2 (1 mM) augmented medium. The overall result suggests that tyrosol exerts a protective effect under heavy metal-induced stress, which could be useful in enhancing the quality of fermented products. [ABSTRACT FROM AUTHOR]

In this investigation, growth promoting role of indole-3-acetic acid (IAA) was assessed on yeasts representing three genera and four species viz Wickerhamomyces anomalus, Saccharomyces cerevisiae, Candida tropicalis and Candida glabrata isolated from traditional fermentative starter materials of Ahom, Rabha, Bodo, Karbi, Kachari and Mishing communities of Assam, India. Isolates were first assessed for their ability to synthesize IAA in presence and absence of external tryptophan and was examined for stimulatory effect of growth on the tested isolates. Tryptophan dependent IAA synthesis was observed in 92% of isolates while 72% of isolates could synthesize IAA in absence of exogenous tryptophan. Candida glabrata KC3X could synthesize maximum IAA while Saccharomyces cerevisiae KR5.6 did not synthesize IAA in presence of external tryptophan. 3 out of 14 Wickerhamomyces isolates and the sole Saccharomyces isolate KR4.10 were found to synthesize significant amount of IAA in absence of tryptophan. Treatment of exogenous IAA on the growth of tested yeasts revealed that Saccharomyces isolates were more pronounced than others. Wickerhamomyces anomalus, Candida tropicalis and Candida glabrata did not show any significant response of growth in presence of exogenous IAA. This study concludes that plant condiments present in starter materials may aid in accelerated growth of Saccharomyces yeasts compared to non-Saccharomyces ones. Yeasts capable of synthesizing IAA but unable to show appreciable growth in presence of IAA may presumably facilitate sustenance of Saccharomyces spp. in fermentative consortia. [ABSTRACT FROM AUTHOR]

Background: In the past few years, there has been an increase in infections caused by fungal aetiology. This is mainly due to increase in sizes of populations which are at risk. Also, fungi which were previously considered as non-pathogenic have been increasingly implicated. Hence, this study was taken up. Aim: To assess the magnitude of mycotic infections in this set up. To assess the spectrum of fungi which are involved in various infections. Material and Methods: Total 704 samples taken over two and half period were included. They consisted of various samples like sputum, blood, urine, sterile body fluids, corneal scrapings. These were processed by conventional mycological techniques. These included direct microscopy after Gram staining and KOH mount, culture on Sabouraud's dextrose agar (SDA), corn meal agar, brain heart infusion (BHI), brain heart infusion agar (BHIA) and others, as required. For non-albicans Candida, the automated Vitek 2 C system was used. Various moulds and yeasts were identified up to genus level and species level. Results: Of 704 samples, 336 (48%) were positive for fungal culture. Of these, 244 isolates were yeast like fungi, 81 were moulds, 7 were yeasts and 4 were dimorphic. Among blood stream infections, non-albicans Candida were the commonest isolates. In the urine samples, C. albicans was the commonest isolate. From corneal scrapings, only moulds and dimorphic fungi were isolated. Conclusion: Incidence of non- albicans Candidal infections is increasing. Culture and identification of mycotic infections is essential for commencement of suitable antifungal therapy. [ABSTRACT FROM AUTHOR]

A nutrition survey carried out in India revealed that the diets of the rural population are inadequate and deficient in most of the nutrients especially protein. India being the 5th-largest producer of soybean, a protein-rich cereal, can redress protein-energy malnutrition through diversification of soybean uses by developing high-value and health-based food products. Tofu, a nonfermented soybean product rich in high-quality protein, B-vitamins, and isoflavones, could be an excellent substitute for meat in Indian recipes. Tofu being rich in protein has a very short shelf life. Hence an attempt was made to improve the shelf life using extracts of tulsi ( Ocimum sanctum) commonly available in rural areas. Tofu was prepared traditionally using MgCl2:CaSO4 as coagulating agents. Aqueous extract of Ocimum sanctum (tulsi) was added during the preparation and storage of tofu to prolong its shelf life. Water used in this study was free from microflora, plant extract used contained mesophilic count of 2.527 × 104 CFU/g, and no yeasts and molds were detected. Tofu with tulsi extract had 76.4% moisture and was softer than control. Not much difference in mesophilic count was observed between control and treated samples during storage; however, treated tofu was organoleptically good until the end of the study with less lipid-peroxidation and exhibited 50% (4.7 units) less protease activity than control (9.6 units) after 7 d. By using extracts of naturally available, easily cultivable tulsi, the shelf life was successfully extended to 7 to 8 d from 3 to 4 d of normal storage without refrigeration. [ABSTRACT FROM AUTHOR]