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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]

Purpose: To assess the effect of combination probiotic Saccharomyces boulardii CNCM-I 3799 and Bacillus subtilis CU-1 in outpatient management of acute watery diarrhea in children. Methods: A randomized double-blind placebo-controlled study was conducted in 180 participants aged six months to five years with acute mild to moderate diarrhea. All were enrolled from six centers across India and centrally randomized to receive S. boulardii CNCM-I 3799 and B. subtilis CU-1 or a placebo along with oral rehydration salts and zinc supplementation. Each participant was followed up for three months to assess recurrence of diarrhea. Results: The mean duration of diarrhea in the probiotic and placebo groups were 54.16 hours and 59.48 hours, respectively. The difference in the duration of diarrhea in those administered with probiotic or placebo within 24 hours of diarrhea onset was 25.21 hours. Furthermore, the difference in duration of diarrhea was 13.84 hours (p<0.05) for participants who were administered with probiotics within 48 hours. There were no significant differences in the stool frequencies between the two arms. After three months, 15% in the probiotic group and 18.5% in the placebo group reported episodes of diarrhea. The mean duration of diarrhea was considerably lower in the probiotic group, 31.02 hours versus 48 hours in placebo (p=0.017). Conclusion: S. boulardii CNCM-I 3799 and B. subtilis CU-1 combination was effective in reducing the duration of diarrhea when administered within 48 hours of diarrhea onset. Similarly, it reduced recurrence of diarrhea and its intensity in the subsequent three months. [ABSTRACT FROM AUTHOR]

Aim: Tyrosol, a quorum sensing molecule in yeasts, was reported to reduce lag phase and induces hyphae formation during cell proliferation. However, evidence of any enhancing effect of tyrosol in cellular proliferation within fermentative environment is unclear. In this investigation, selected yeast cells were assessed for their ability to synthesize tyrosol followed by examining the role of the molecule during fermentation. Methods and Results: Tyrosols were characterized in four fermentative yeasts viz., Saccharomyces cerevisiae, Wickerhamomyces anomalus, Candida glabrata and Candida tropicalis isolated from traditional fermentative cakes of northeast India. All the isolates synthesized tyrosol while C. tropicalis exhibited filamentous growth in response to tyrosols retrieved from other isolates. Purified tyrosols showed protective behaviour in C. tropicalis and S. cerevisiae under ethanol mediated oxidative stress. During fermentation, tyrosol significantly enhanced growth of W. anomalus in starch medium while C. tropicalis exhibited growth enhancement in starch and glucose sources. The chief fermentative yeast S. cerevisiae showed notable enhancement in fermentative capacity in starch medium under the influence of tyrosol con‐commitment of ethanol production. Conclusion: The study concludes that tyrosol exerts unusual effect in cellular growth and fermentative ability of both Saccharomyces and non‐Saccharomyces yeasts. Significance and Impact of the Study: This is the first report of expression of tyrosol by non‐conventional yeasts, where the molecule was found to exert enhancing effect during fermentation, thereby augmenting the process of metabolite production during traditional fermentation. [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]

Probiotics are increasingly used in critically ill patients without enough safety data. The aim of the present study was to determine the association of probiotics with Saccharomyces cerevisiae fungaemia. Seven patients with S. cerevisiae fungaemia were reported at two hospitals in India between July 2014 and September 2015. Detailed clinical history of patients was recorded. Besides the seven patient isolates, three probiotics sachets used in those patients and five unrelated clinical isolates were used for association study by Fluorescent amplified fragment length polymorphism ( FAFLP). Antifungal susceptibility testing was performed by broth microdilution technique of CLSI (M27-A3) and interpreted according to CLSI (M27S4). Two patients were premature neonates and five were adults. They were admitted in intensive care unit and were on probiotics containing S. boulardii (except one adult patient). FAFLP analysis showed 96.4-99.7% similarity between blood and corresponding probiotic isolates. Of the three AFLP types (group I, II, II) identified, all the probiotic isolates clustered in group I (major cluster) including majority of the blood isolates. The isolates were susceptible to all antifungal agents tested. Five patients, who could be evaluated, responded promptly to echinocandins or voriconazole. As the prescription of probiotic containing S. boulardii in critically ill patient's leads to the fungaemia, we recommend avoiding this probiotic in those patients. [ABSTRACT FROM AUTHOR]

Background Several newly recognized yeast species have been reported to be associated with fungal infections. We describe first report from India of isolation of Cyberlindnera fabianii and Wickerhamomyces anomalous from blood samples of newborns. Methods Nine fungal isolates phenotypically identified as Pichia sp. by MICROSCAN were obtained from newborns suspected to be suffering from blood stream infections. The blood samples were processed in BACTEC Culture Vials. Gram stain and subculture on blood agar were performed from each positive vial. Small, white colonies were obtained on blood agar plates after 24 hours of incubation. The 3-day yeast colonies were subjected to DNA extraction using commercially available DNA extraction kit. Purification of the PCR products and DNA sequencing was done commercially. Antifungal susceptibility test of Cyberlindnera fabianii isolates against fluconazole and amphotericin B was carried out using E strips. Results Eight and one strains were identified as Cyberlindnera fabianii and Wickerhamomyces anomalous respectively. Except 3 fluconazole susceptible isolates, rest all results were resistant or susceptible dose-dependent. Conclusions This is first report of Cyberlindnera fabianii and Wickerhamomyces anomalous fungemia from India. We advocate importance of molecular assays in confirming the identity of rare fungal isolates, as accurate identification is imperative for appropriate management. [ABSTRACT FROM AUTHOR]

Abstract: An experiment was conducted to study the effects of yeast (Saccharomyces cerevisiae; SC) supplied from dried distillers rice grains with solubles (DGS) with or without a trace mineral mixture (TM) on the performance and nutrient utilization in Black Bengal (Capra hircus) kids. The study was designed in a 3×2 factorial arrangement with three doses of DGS with or without TM. Twenty-four kids (3–5 months age and 5.99±0.76kg initial body weight) were equally divided into six groups with four kids in each group (designated as C0, T1, T2, C1, T3, and T4). Two concentrate diets were prepared, one without TM and other with TM. Goats in C0, T1 and T2 groups were fed on the concentrate diet without TM, and 0, 15 and 20g DGS/animal/day, respectively. Goats in C1, T3 and T4 groups were fed on the TM concentrate diet, and 0, 15 and 30g DGS/animal/day, respectively. The DGS supplied 7×106 cfuSC/g. The trial lasted for 90 days. The SC supplementation improved (P< 0.05) average daily gain (ADG) and feed intake. The digestibilities of organic matter, crude protein, neutral detergent fiber and acid detergent fiber increased linearly (P< 0.05) with increasing doses of SC supplementation. The addition of SC did not influence serum trace mineral status. TM supplementation had no effect (P >0.05) on ADG, intake and digestibilities of nutrients. Absorbability and retention, and serum concentrations of Cu, Zn, Mn and Fe were significantly improved (P< 0.05) in all TM supplemented groups compared with non-mineral supplemented groups. It can be concluded that SC supplementation in kids may increase growth, feed intake and nutrient utilization, but TM supplementation had no influence on growth and nutrient utilization. [Copyright &y& Elsevier]

Abstract: The natural Saccharomyces and non-Saccharomyces yeast flora present on the grape berries significantly affect wine production. Six grape varieties, Bangalore blue, Zinfandel, Cabernet, Chenin Blanc, Sauvignon Blanc and Shiraz are being used in India for wine making. The yeast diversity was studied on the basis of morphological, colony, physiological characteristics and 5.8S-ITS sequencing of rDNA of the isolates. Eleven different species belonging to seven genera were identified as: Candida azyma, Candida quercitrusa, Debaryomyces hansenii, Hanseniaspora guilliermondii, Hanseniaspora viniae, Hanseniaspora uvarum, Issatchenkia orientalis, Issatchenkia terricola, Pichia membranifaciens, Saccharomyces cerevisiae and Zygoascus steatolyticus. H. guilliermondii was the predominant species while S. cerevisiae was observed occasionally in the six vine varieties. For the first time, C. azyma was isolated from Bangalore blue and Cabernet varieties grown in different localities. This association may be attributed to the change in cropping pattern from sugarcane to viticulture in the vine growing regions and the known association of C. azyma with sugarcane phylloplane. Further analysis of the indigenous strains and the qualitative and quantitative changes in the flora during fermentation will be useful to understand wine quality and to design preservation strategies to control wine spoilage. [Copyright &y& Elsevier]

• The fermentation characteristics of toddy were studied. • Co-existence of bacteria and fungi during natural fermentation of toddy. • Leuconostoc and Hanseniaspora were abundant in the early stages of fermentation. • Lactobacillus, Gluconoacetobacter and Saccharomyces were abundant in later stages. • Functional profiles such as metabolites, vitamin and amino acids were predicted. Toddy is a traditional mild-alcoholic drink of India, which is produced from fresh palm saps by natural fermentation. We studied the successional changes in bacterial and fungal communities during the natural fermentation (0 h–96 h) of toddy. During fermentation, alcohol content of the fermenting saps increased significantly from 0.6 %±0.15 to 5.6 %±0.02, pH decreased from 6.33 %±0.02–3.93 ± 0.01, volatile and titratable acidity acidity (g/100 mL) increased from 0.17 ± 0.02 (0 h) to 0.48 ± 0.02 (96 h) and 1.30 ± 0.005 (0 h) to 2.47 ± 0.005 (96 h), respectively. Total sugar content and ˚BRIX also decreased during the fermentation. Firmicutes (78.25 %) was the most abundant phylum followed by Proteobacteria (21.57 %). Leuconostoc was the most abundant genus in the early stages of fermentation. However, Lactobacillus and Gluconoacetobacter were found abundant with increase in pH during the later phases of fermentation (72 h–96 h). Ascomycota (99.02 %) was the most abundant fungal phylum. Hanseniaspora was the abundant yeast in the initial stages of fermentation, whereas the population of Saccharomyces increased significantly after 24 h of fermentation. Torulaspora , Lachancea and Starmerella showed their heterogeneous distribution throughout the fermentation. Computational analysis of metagenomes based on KEGG and MetaCyc databases showed different predictive functional profiles such as folate biosynthesis, glutathione metabolism, terpenoids biosynthesis and biosynthesis of amino acids with significant differences between the fresh palm saps and fermenting saps during toddy fermentation. [ABSTRACT FROM AUTHOR]

Objective: To see the efficacy and safety of 250 mg of Saccharomyces boulardii twice daily for 5 d in acute childhood diarrhea., Methods: Children aged between 3 mo and 59 mo with acute onset diarrhea (of less than 48 h) admitted in DTTU (diarrhea treatment and training unit) were included and those with clinical evidence of severe malnutrition, systemic infection, encephalopathy and/or convulsion, electrolyte imbalance, invasive diarrhea or previous use of any probiotics were excluded from the study. Those included randomly were given either a placebo or Saccharomyces boullardi (SB) in identical packets mixed with puffed rice powder., Results: Mean post intervention duration of diarrhea was significantly (95% CI = -28.13 to -5.43) shorter in SB group (52.08 ± 24.57 h) as compared to placebo group (64.04 ± 30.43 h). The time of appearance of first semi formed stool in SB group (39.48 ± 23.09 h) was significantly (95% CI -25.4 to -3.87) shorter than the placebo group (54.13 ± 28.21 h). No statistically significant difference was found in rest of the parameters., Conclusions: There is initial evidence available that SB may have a therapeutic role in the management of acute childhood diarrhea.