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ThesisItem Open Access Evaluation of mycobiota of spoilt wheat in expediting ethanol production(CCSHAU, 2014) Preeti; Goel, SnehEthanol besides being a known feedstock for chemical and beverage industry is also being used as an additive to fuel for automobiles. Over the years, its demand in general, has been on an increase and India is no exception. Clearly, maximization of ethanol production becomes imperative and could be achieved by considering, among others, the addition of yeast nutrients to the fermentation liquor. These nutrients by accelerating the rate of fermentation reduce the fermentation time and in turn lead to maximization of ethanol volumes on a daily basis. Usually, N and P represent these nutrients and in the Indian distilleries they are conventionally sourced from chemical fertilizers, which do have a certain carbon footprint. Ideally, organic/ renewable yeast nutrients would be more suitable, as they have a low net green house gas emission. However, so far, no dedicated nutrient formulation is available in the Indian market. Spoilt wheat which ferments faster than its normal version has been shown to offer a potential for such a formulation, as it contains factor(s)/activity that is responsible for expediting rate of ethanolic fermentation. This ethanol-expediting activity has been speculated due to in situ production of yeast nutrients viz., low molecular weight peptides and free amino acids by the activities of resident bacterial and fungal flora of spoilt wheat. So, fungal flora of spoilt wheat was screened for its ethanolexpediting capability, leading to the retrieval of the best isolate. Such an isolate might later contribute to the development of more useful, environment friendly and activity-enriched wheat-based supplements to expedite ethanolic fermentation by yeast. The spoilt wheat (SW) sample tested positive for ethanol-expediting activity on 30% normal wheat (NW) hydrolysate, as its supplementation @ 15%, both as coarse flour or its aqueous extract, produced 10.6% and 11% (v/v) ethanol, respectively, against 8% (v/v) by the control. Clearly, the SW sample under study was fit for isolation of fungi. Based on colony morphology, 30 fungal isolates were recovered from the SW sample. Screening of the isolates for amylolytic, proteolytic and lipolytic activities on the plate revealed that all the 30 isolates were positive for the amylolytic, 13 were positive for proteolytic and 18 for the lipolytic activities. Thus, only three bacterial isolates viz., SWF-6, SWF- 11 and SWF-20 having dissolution factor of >1 were further utilized to explore their ethanol-expediting capabilities by producing laboratory spoilt wheat grains and subsequently estimating ethanol production by yeast on 30% laboratory developed spoilt wheat as well as on 30% normal wheat (NW) hydrolysate, as its supplementation @ 15%, both as coarse flour or its aqueous extract. Ethanol estimation at 24h showed that three isolate viz., SWF-6, SWF-11 and SWF-20 did produce a boost to alcohol production from 11 to 12.2% (v/v). These three isolates based on morphological characterization were identified to belong most probably to genus Aspergillus.