title: Bioprospecting of thermo- and osmo-tolerant fungi from mango pulp-peel compost for bioethanol production.
abstract: The persistent edaphic stress on microbial succession due to dynamic changes during composting was explored for selection of multi-stress tolerant microbe(s) desirable for ethanol production. A total of 23 strains were isolated from mango compost using four successive enrichments in YP broth (g l(-1)): glucose, 100; 150; 250 with ethanol (40) and cycloheximide (0.4) at 40 °C, pH 6.0. Based on multi-gene ribotyping, 14 yeasts (61 %) of Saccharomycetaceae, 2 filamentous fungi (8.6 %) and 7 bacteria (30.4 %) were obtained. Phenetic and phylogenetic analysis of the 14 yeasts revealed 64.3 % tolerant to 500 g l(-1) glucose, growth at 45 °C and resemblance to Candida sp. (14.3 %), Kluyveromyces marxianus (35.7 %), Pichia kudriavzevii (21.4 %) and Saccharomyces cerevisiae (28.6 %). Assessment of the 14 yeasts in glucose fermentation medium (pH 4.5 at 40 °C) showed ethanol productivity of ≥92 % by 12 yeasts with theoretical yields of 90-97 %. Fermentation of molasses (150 g l(-1) glucose equivalent) by P. kudriavzevii D1C at 40 °C resulted in 73.70 ± 0.02 g l(-1) ethanol and productivity of 4.91 ± 0.01 g l(-1) h(-1). Assessment of P. kudriavzevii D1C revealed multi-stress tolerance towards 5-hydroxymethyl furfural, ethanol (20 %, v/v), high gravity and H2O2 (0.3 M) indicating suitability for ethanol production using high gravity molasses and pre-treated lignocellulosic biomass fermentation.
authors.affiliation: School of Life Sciences, North Maharashtra University, P.O. Box 80, Jalgaon, 425001, Maharashtra, India.
authors.forename: N D
authors.initials: ND
authors.lastname: Dandi
authors.forename: B N
authors.initials: BN
authors.lastname: Dandi
authors.forename: A B
authors.initials: AB
authors.lastname: Chaudhari
mesh_terms: D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005658:Fungi / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*; D005838:Genotype; D005947:Glucose / Q000378:metabolism; D031022:Mangifera / Q000382:microbiology*; D016533:Mycological Typing Techniques; D010641:Phenotype; D021521:Ribotyping; D012988:Soil Microbiology
chemical_list: D000431:Ethanol; D005947:Glucose