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A field experiment was conducted at ARS, Bhavanisagar, during summer 2021, to investigate the effect of multi-nutrient-loaded electrospun PVA nanofibre on the green gram. The nanofibre developed from polyvinyl alcohol (10%) infused with macro and micronutrients. The nanofibre coated seeds recorded the higher plant height (44.97 cm); crop growth rate (1.5- 18.43 g m-2 d-1); leaf area index (0.56-1.84 m2m-2) and leaf area duration (13.29-34.77days). Further, the higher grain yield (854.2 kg ha-1) and haulm yield (1100 kg ha-1) were obtained from the nanofibre-coated seeds. According to the findings of this study, nanofibre technology is a novel idea for the fertilizer sector because it reduces fertilizer use and increases nutrient use efficiency.

Pichia pastoris remains an amicable host for the expression of heterologous protein from eukaryotes. Achieving a high level of expression of yeast in the recombinant host has remained a challenge. Apart from the codon preference of genes and proper protein folding for efficient expression of the heterologous gene, the main bottleneck is to efficiently integrate the heterologous gene into the host DNA. The present study evaluated the choice of available transformation methods such as lithium chloride, electroporation, and spheroplast for efficient integration of xylose reductase (Xr) gene of Candida tropicalis in P. pastoris. The results revealed that electro transformation was found to be an efficient method for the transformation for xr in P. pastoris, yielding 1 x 106 transformants, followed by the lithium chloride method registering 2 x 103 transformants.

Nodule associated endophytic yeasts have attracted much attention dueto its potential plant growth-promoting activities and protecting legumecrops from both biotic and abiotic stress. The present study evaluated thepotential role of an endophytic yeast Candida tropicalis VYW1 in modulatinghost fitness (blackgram) both as a single inoculant and co-inoculant withRhizobium sp. VRE1. The results showed that nodule associated endophyticyeast C. tropicalis VYW1 when co-inoculated with Rhizobium sp. VRE1significantly increased the germination percent (100%), root (34.6 cm),and shoot length (32.8 cm). The vigor index was also maximum (4250) inthe treatment that received the co-inoculation of Rhizobium sp. VRE1 andC. tropicalis VYW1 besides registering enhanced hydrolytic enzyme,α - amylase, and protein content in seeds. Metabolite profiling of bacterialprimed seed exudates revealed 30 diverse compounds belonging to theclasses viz., sugars, amino acids, organic acids, flavones, prenol lipids,and fatty acids. The blackgram seeds primed with co - inoculants releasedhydroxyl benzoic acid and galactopyranose, which act as potential chemoattractantsand involves in the lectin complement pathway regulatingfructose mannose metabolism. These metabolites lead to a significantincrease in germination and nodulation in blackgram seedlings. Hence,the study suggests the scope of enhancing the fitness of blackgram usinga co-inoculant comprising of C. tropicalis VYW1 and Rhizobium sp. VRE1.

The impact of moisture stress tolerant Bacillus altitudinis FD48 in promotingseed germination and physiological phenomenon under water deficit wasevaluated. Rice seeds (Var CO51) biotized with B.altitudinis FD48 enhancedthe seed germination and seedling vigor index by 51.05% followed byMethylobacterium sp.,(37.3%) moisture stress seedlings (-0.7 Mpa osmoticpotential). Plant biomass, accumulation of proline and compatible sugars alsoincreased in FD48 treated seeds under moisture stress. Further, the alphaamylase activity also accelerated with increase in moisture stress intensity. GCMSprofiling of bacterial primed seed exudates revealed 35 diverse compoundsbelonging to the class viz., sugars, aminoacids, organic acids, flavones, prenollipids and fatty acids. The B. altitudinis FD48 primed seeds alone releasedmethoxy flavone which may act as a lure for recruiting beneficial rhizosphericbacteria. Hence, this study implies that seed priming with B.altitudinis FD48is a promising approach for enhancing seed germination and seedlingestablishment in rice for drought prone areas and subsequent recruitment ofbeneficial bacteria that promotes plant growth and fitness.

A study was undertaken to determine the physico-chemical characteristicsof sago wastewater (SWW) from various sago industries in Salem andNamakkal districts of India. Besides, different SWW (raw wastewater,aerobic wastewater, treated wastewater and starch wastewater) from withinthe industry were evaluated. The results concluded that effluents from thisregion are whitish and greyish brown in color with majority supra-colloidalor settable suspended solids with high TS, TSS, and TDS. The ammoniacal,nitrate, and nitrite nitrogen ranged from 2.7 to 6.5, 4.5 to 19.1, and 0.4to 2.8 mg.L-1. The total nitrogen content of SWW samples was ranged from180- 650 mg.L-1. The phosphate level of SWW was very high (640-1096 mg.L-1). The COD and BOD content of SWW from all the industries ranged from2560 to 3200 mg.L-1 and 34000 to 76000 mg.L-1 indicates its high organicnature. SWW effluents are acidic in nature (pH 4.3-5.2). The free cyanide(CN) content was ranged from 1.2 to 5.2 mg.L-1. The treated wastewater hadneutral pH (pH - 6.2), and had a reduced level of EC, starch content, TSS,COD and BOD.

An aerobic, rod shaped, mesophilic, gram positive xylitol producing bacterial isolates were made from different enriched substrates. Xylose isomerase is an enzyme that catalyzes the interconversion of D-xylose and D-xylulose. The microbes producing xylulose from xylose via xylose isomerase enzyme were screened for the xylose isomerase activity based on 2, 3, 5-Triphenyl tetrazolium dye retention capacity. Among the fourteen isolates screened, only six isolates showed the positive results by retaining the dye of which XLY3 was the best. Phylogenetic and sequence analysis of 16SrRNA gene showed 98 % homology to Bacillus endophyticus

Gibberellins (GAs) are a group of diterpenoid acids with ent-gibberellane skeleton that function as plant growth regulators influencing a range of devel- opmental processes in higher plants including stem elongation, germination, dormancy, flowering, sex expression, enzyme induction, leaf and fruit senes- cence (Graebe and Ropers, 1978). Gibberellic acid is a high value, industrially important biochemical, sell- ing high rate in the international market depending on the purity and potency. Gibberellic acid also has potential application in improving seedling establish- ment and seed production in hybrid rice (Carlson et al., 1992). In India up to 1970’s research on gibberel- lic acid mainly focused on the isolation and identifi- cation of GAs from plant sources. Studies conducted at CFTRI, Mysore in 1970s ended with a GA3 yield of0.40 - 0.45 g per litre in submerged fermentation pro- cess (SmF) even after optimizing the culture condition parameters. The efficient strain selection and usage plays key role to make the gibberellic acid production economically viable. The strain improvement strategy for increased GA production can be achieved by mu- tation and protoplast fusion in filamentous fungi like F.fujikuroi. In the present work, we have screened and developed a procedure to obtain effective F.fujikuroi mutants through physical and chemical mutagenesis for increased gibberellic acid production.

Burgeoning population, fastest depletion of fossil fuel resources, alarming global climate change issues are the top most challenge to be addressed for a country to prosperous in energy, environmental and economic security. Greatest attention has been paid on renewable biomass for generation of alternative fuels, bio products and fine chemicals in a sustainable manner. It has been estimated that, every year photosynthesis alone accounts for conversion of 100 billion metric tons of CO2 and H2O to cellulose and other biomass products. Hence biomass driven industry is one of the fastest growing sector, their share on global economy is increasing about 5-20%. The total world annual biomass production is estimated at 2740 quadrillion BTU’s. At present, only about 7% of the annual production of biomass is used.

An ultrasonic pretreatment was evaluated for the delignification of the corncob biomass. The ultra-sonication process was carried in an ultrasonicwater bath for 1 hr, 33 kHz, and 100 watts. Three different pretreatmentcombinations were studied; corncob with distilled water, corncob with buffer,and corncob with buffer and enzyme (Tramates versicolor), and assessedfor lignin reduction, hemicellulose reduction, and cellulose increase. Theresults indicated that sonication of corncob biomass with the enzyme yielded44.19%, 6.74%, and 15.39% of lignin and hemicellulose reduction andcellulose increase, respectively. In FTIR, a reduction in peak intensity for ligninat wavenumbers 1697.05 cm-1, 1534.1 cm-1 and 1328.71 cm-1 was noticed.Thus, ultrasonic pretreatment can be effectively used for the delignificationof corncob biomass.

Endophytes associated with C4 perennial grasses are a treasure trove of biocatalysts, and have emerged as a viable option for biofuel production. Studies were conducted to investigate the production of extracellular cellulases and xylanases from newly isolated Bacillus tequilensis BT5 and Alcaligenes faecalis B12 from perennial grass (Neyraudia reynaudiana L.). The total cellulase activity (FPase) for B. tequilensis BT5 and A. faecalis B12 were recorded as 0.61 and 0.34 FPU.ml-1 at 28 h and 32 h, respectively. Similarly, β-glucosidase, carboxymethyl cellulase (CMCase) and exoglucanase activities of BT5 and B12 were 1.12 and 0.94 U.ml-1; 0.92 and 0.86 U.ml-1 ; 1.98 and 1.58 U.ml-1, respectively. Xylanase activities of 1.58 U.ml-1and 1.22 U.ml-1 at 28 h and 36 h for B. tequilensis BT5 and A. faecalis B12, respectively were also recorded. Furthermore, the presence of cellulases and xylanases genes was confirmed by PCR screening using the gene-specific primers. This study revealed that the cellulases and xylanases from endophytic bacteria from perennial grasses could serve as a natural reservoir for biomass deconstruction and production of cellulose derived commodities.

Plant-derived cellulose (PC) and bacterial cellulose (BC) show poor solubility in common solvents due to the strong inter and intramolecular hydrogen bonding supported by a rigid backbone structure. Dissolving cellulose is the foremost requirement in order to facilitate the application of cellulose to develop various high-end applications like membrane filter, template for drug delivery, agro chemicals, hydrogel, etc. The present investigation was aimed at developing a solvent-based method to dissolve the bacterial cellulose (BC), an exopolysaccharide produced by the gram-negative strain Acetobacter senegalensis MA1 in order to widen the BC application more specifically in packaging, food and pharma industries. Two solvents namely trifluoroacetic acid (TFA) and dimethylsulphoxide (DMSO) were employed as a uni-component in three different conditions viz., conventional (60°C), microwave and cold treatment (0°C) and the results revealed that microwave treatment facilitated early dissolution of BC. Furthermore, FT-IR analysis of the regenerated BC (BC-R) confirmed the absence of TFA, suggesting that all the TFA might have volatilized during the regeneration process. The volatilizing of TFA during the process of regeneration favours the usage of this solvent for the fabrication of BC nanofibres via electrospinning, which finds applications in various fields.

Xylitol is a functional sugar alcohol widely used as a sugar substitute. Chemical route of xylitol production is highly expensive, whereas microbial sources offer lower yield and conversion efficiency. In the present investigation, xylose reductase (XR) gene from Candida tropicalis GRA1 was cloned in pQE30Xa vector and transformed into E. coli M15. The resultant recombinant strain produced xylitol from xylose that harboured Xr gene transcribed under the control of lac operon. Such transcribed Xr protein converts xylose into xylitol using NADPH as a co-factor. Xylitol production was achieved by the recombinant E. coli M15 pQE30XrCt under shake-flask fermentation (2.1 g.l-1 in 24 h) with xylose as the sole substrate in the medium. Addition of co-substrate, glucose in the growth medium enhanced the xylitol production to the tune of 3.4g.l-1. Furthermore, the addition of co-substrate glycerol along with xylose enhanced a xylitol yield of 6.4g.l-1.