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The conversion of biobased feedstocks into energy and value-added chemicals is one main approach to address the current global challenge for waste mitigation through the biorefinery mode. Corncob biomass which is one of the most abundant agricultural residue in India with a high hemicellulose content, can serve as a potential low-cost raw material for food-grade xylitol production. The present study demonstrates a process for xylitol production from corncob biomass with detailed energy and life cycle analysis for viability assessment. The major highlight of the process is the use of microbial fermentation, where biomass-derived D-xylose is converted to xylitol with high selectivity. Overall, 0.502 kg of xylitol crystals could be produced from 3.5 kg of corncob biomass. Simulation analysis revealed that the evaporators are the primary consumers of energy, and the process of heat integration can significantly reduce the energy requirements of the overall process. Environmental impacts of the system evaluated showed emission results of 8.68 kg CO2 equivalent and revealed that marine aquatic and freshwater eco-toxicity are the only possible contributors to the environment. The results suggest that the process would have favourable energy balances, which can be used in pilot plant and heat exchanger network design and operation for xylitol production scale up to 500 L.

Fetal Bovine Serum (FBS) is an expensive source of macronutrients which are required for proper nutrition of Leishmania parasite in the culture medium. An alternative, cost effective source of macronutrients which can replace the use of FBS in tissue culture medium is required. The potential of Soy Protein Isolate (SPI) to replace FBS in RPMI-1640 medium for the in vitro cultivation of Leishmania donovani was evaluated. Commercially available SPI powder was used in RPMI-1640 medium as a substitute of FBS to cultivate L. donovani promastigotes. The growth, multiplication and morphology of cultivated parasites was observed in conventional RPMI-1640 with 10% FBS (v/v) and RPMI-1640 containing 10% SPI (v/v) by using light microscopy, measurement of absorbance and cell counting. The growth of Leishmania promastigotes in the medium containing 10% SPI was slower in initial phase; however, the parasites were morphologically larger as compared to those in RPMI-1640 medium containing 10% FBS. Cell count in the SPI-containing RPMI-1640 medium was 2.3 × 108 cells/ml whereas it was 1.9 × 107 cells/ml in RPMI-1640 with 10% FBS. This study concludes that RPMI-1640 may be supplemented with SPI instead of FBS for the in vitro cultivation of Leishmania donovani promastigotes to decrease the culture maintenance cost in developing countries.

The present study was aimed to evaluate the in vitro antileishmanial activity of four different concentrations of natamycin and nystatin by using MTT 3-(4.5-dimethylthiazol-2-yl)-2.5-diphenyl tetrazolium bromide reduction assay. In vitro antileishmanial activity revealed that the IC50 of natamycin (80.49 μg/ml) and nystatin (105.7 μg/ml) was less than that of sodium stibogluconate (127.9 μg/ml), and more than amphotericin B (18.91 μg/ml).

Worldwide, sugarcane industries produce tons of sugarcane bagasse as residual/waste material. This residual material is rich in complex lignocellulosic substances and may be used as a low cost carbon and energy source for the growth of fungal species. The present work was aimed at designing a sugarcane waste-based medium as a substitute for expensive commercial media for growing fungal cultures. Eight species of fungi, namely, Aspergillus niger, Candida albicans, Saccharomyces cerevisiae, Fusarium sp., and four unidentified species F1, F2, F3, and F5, were grown on the sugarcane bagasse medium which produced remarkable results and competed with standard media like potato dextrose agar, Sabouraud dextrose agar, and cornmeal agar. The designed medium was able to provide nourishment to the fungi as well as prevent the growth of any bacterial or fungal contaminant. The production of spores was more in the sugarcane medium as compared with standard media. Hence, this study led to the discovery of a new and efficient medium for fungal cultures as well as decrease in the waste disposal expenses and efforts.

Rise in global fuel demands and approaching towards the ‘peak-oil,’ liquid fuels from non-fossil resources are being considered as promising alternatives. Yeast single cell oil is gaining significant attention as feedstock for biofuels or oleochemicals over tree-borne or algal oil. In the present work, the oil-producing capacity of an oleaginous yeast Rhodotorula mucilaginosaIIPL32 has been enhanced to 1.18-fold by overexpressing the cytosolic malic enzyme through genome integration and cultivating the yeast on sugarcane bagasse derived xylose on 15 L fermenter scale. Detailed in silico modeling and docking study of the malic enzyme of R. mucilaginosa was also carried out to understand its interaction with cofactors involved in lipogenesis. Estimation of fuel properties revealed that the lipid produced by transformed yeast complies with fourteen out of the seventeen fuel properties in the EU, Indian and US standards. We conclude with the plausible use of the engineered yeast for industrial production of oil as an alternative to plant-borne oil for biofuel production in a lignocellulosic-biomass-based biorefinery.

Gentiana kurroo Royle, native to North- Western Himalayas, is one of the critically endangered perennial herbs, which is being overexploited due to its multiple medicinal uses. The goal of this work was to develop a protocol for somatic embryogenesis and efficient plant regeneration through cell suspension culture. Selected ranges of plant growth regulators were experimented for somatic embryogenesis. Light micrographs of the established suspension cell cultures of somatic embryos at different developmental stages were also observed under light microscope. Somatic embryogenesis was induced from the leaf explants and the maximum induction frequency (97.2%) was obtained on Murashige and Skoog (MS) medium supplemented with 0.5 mg/l each of NAA, BAP and TDZ. Cell suspension cultures were established in MS liquid medium containing IAA (0.5 mg/l) + BAP (1.0 mg/l) with 89-93% viable cells. Transfer of cotyledonary somatic embryos to the MS agar medium containing 2, 4-D (0.4 mg/l) and KN (1.5 mg/l) resulted in somatic embryogenesis at high frequencies (80%) with an average of 28 ± 0.2 embryos/ callus piece. After transfer onto the half strength MS medium without growth regulators approximately 80-90% somatic embryos developed into complete plantlets. The protocol described here could be used for somatic hybridization, genetic transformation, isolation of protoplasts and large-scale propagation of G. kurroo.

The present study was aimed at in vitro antileishmanial screening of ten plants used in the traditional medicine in India. MTT method was used to evaluate the cell death after application of 100, 250, 350 and 500 μg/mL of the methanolic extracts followed by incubation for 24 hours at 25°C. Methanolic leaf extracts of Acorus calamus, Alstonia scholaris and Berberis aristata showed significant antileishmanial activity at a concentration of 500 µg/ml. In order to identify the antileishmanial compounds present in the active extracts of the screened plants, an LC-MS analysis of the tested extracts was carried out. The active extracts revealed the presence of some natural products with known antileishmanial activity along with other compounds. The present study suggests that the active plant extracts may be processed to isolate the compounds that may further be screened for their antileishmanial potential.