Potential of Bran from Two Varieties of Rice (Oryza) Spp for Bioethanol Production

Second generation ethanol is produced from non-food based including waste from food crops, wood chips and agricultural residue. Lignocellulosic and starchy materials in them are converted to fermentable sugars which are further processed to produce bioethanol. Rice bran is an agricultural residue with abundant carbohydrate for bioconversion into ethanol. This study was designed to evaluate the potential of two varieties of rice bran (Sipi and Wita) to produce bioethanol. Compositional analysis of Wita rice bran showed 40% cellulose, 23% hemicellulose and 16% lignin content. Sipi variety contains 35% cellulose, 27% hemicellulose and 13% lignin content. Sodium hydroxide pretreatment was carried out at different concentrations (0.5%, 1%, 2% and 3%) and residence time of (15, 30, 60, and 90min). It was observed from the present study, pretreatment of rice bran with 2% NaOH for 90min is considered as effective pretreatment condition for bioethanol production from rice bran. Simultaneous saccharification and fermentation of cellulosic biomass was carried out for 72h with Saccharomyces cerevisae and Mucor indicus. Fermentation of Wita variety with S.cerevisiae produced highest bioethanol yield of 1.36% while Mucor indicus produced 0.75% bioethanol yield. From the result of these findings, it can be concluded that rice bran could be considered as a promising substrate for the fermentation of second generation ethanol.

Potential of Bran from Two Varieties of Rice (Oryza) Spp for Bioethanol Production

Second generation ethanol is produced from non-food based including waste from food crops, wood chips and agricultural residue. Lignocellulosic and starchy materials in them are converted to fermentable sugars which are further processed to produce bioethanol. Rice bran is an agricultural residue with abundant carbohydrate for bioconversion into ethanol. This study was designed to evaluate the potential of two varieties of rice bran (Sipi and Wita) to produce bioethanol. Compositional analysis of Wita rice bran showed 40% cellulose, 23% hemicellulose and 16% lignin content. Sipi variety contains 35% cellulose, 27% hemicellulose and 13% lignin content. Sodium hydroxide pretreatment was carried out at different concentrations (0.5%, 1%, 2% and 3%) and residence time of (15, 30, 60, and 90min). It was observed from the present study, pretreatment of rice bran with 2% NaOH for 90min is considered as effective pretreatment condition for bioethanol production from rice bran. Simultaneous saccharification and fermentation of cellulosic biomass was carried out for 72h with Saccharomyces cerevisae and Mucor indicus. Fermentation of Wita variety with S.cerevisiae produced highest bioethanol yield of 1.36% while Mucor indicus produced 0.75% bioethanol yield. From the result of these findings, it can be concluded that rice bran could be considered as a promising substrate for the fermentation of second generation ethanol.

A Revised Species Concept for OpportunisticMucorSpecies Reveals Species-Specific Antifungal Susceptibility Profiles

ABSTRACTRecently, the species concept of opportunisticMucor circinelloidesand its relatives has been revised, resulting in the recognition of its classical formae as independent species and the description of new species. In this study, we used isolates of all clinically relevantMucorspecies and performed susceptibility testing using the EUCAST reference method to identify potential species-specific susceptibility patterns.In vitrosusceptibility profiles of 101 mucoralean strains belonging to the genusMucor(72), the closely related speciesCokeromyces recurvatus(3),Rhizopus(12),Lichtheimia(10), andRhizomucor(4) to six antifungals (amphotericin B, natamycin, terbinafine, isavuconazole, itraconazole, and posaconazole) were determined. The most active drug for all Mucorales was amphotericin B. Antifungal susceptibility profiles of pathogenicMucorspecies were specific for isavuconazole, itraconazole, and posaconazole. The species formerly united inM. circinelloidesshowed clear differences in their antifungal susceptibilities.Cokeromyces recurvatus,Mucor ardhlaengiktus,Mucor lusitanicus(M. circinelloidesf.lusitanicus), andMucor ramosissimusexhibited high MICs to all azoles tested.Mucor indicuspresented high MICs for isavuconazole and posaconazole, andMucor amphibiorumandMucor irregularisshowed high MICs for isavuconazole. MIC values ofMucorspp. for posaconazole, isavuconazole, and itraconazole were high compared to those forRhizopusand the Lichtheimiaceae (LichtheimiaandRhizomucor). Molecular identification combined within vitrosusceptibility testing is recommended forMucorspecies, especially if azoles are applied in treatment.