Genetic Diversity and Anti-Oxidative Potential of Streptomyces spp. Isolated from Unexplored Niches of Meghalaya, India.

Streptomyces is genetically and functionally diverse genus known to produce a wide array of phenolics and flavonoids with significant biotechnological applications. 52 isolates belonging to 26 species of Streptomyces collected from Meghalaya, India were analyzed for their genetic diversity using BOX-PCR. Significant inter- and intra- generic diversity was observed among the Streptomyces isolates especially those belonging to S. cacaoi, S. lavendulae, S. olivochromogenes, S. aureus, S. flavovirens. During bioactivity screening of the isolates, S. rectiviolaceus MJM72 recorded the highest DPPH activity (77.13 ± 0.91%) whereas S. antimycoticus MSCA162 showed excellent ABTS radical scavenging activity (99.65 ± 0.41%). On the other hand, S. novaecaesareae MJM58 had the highest (756.4 ± 7.38 µg GAE g-1 fresh weight) phenolic content while S. rectiviolaceus MJM72 was recorded with the highest flavonoid content (69.3 ± 0.12 µg QE g-1 fresh weight). As compared to total flavonoid content, total phenolic content had a stronger correlation with antioxidant activities. HPLC analysis of five selected isolates showed presence of gallic acid and pyrocatechol as predominant phenolics. In case of flavonoids, three isolates showed presence of rutin with S. rochei MSCA130 having the highest rutin content (0.95 µg g-1 fresh weight). The results of this study showed high genetic diversity and antioxidant potential among the Streptomyces isolates.

Unraveling the mechanism of sulfur nutrition in pigeonpea inoculated with sulfur-oxidizing bacteria.

An investigation was carried out to understand the mechanism(s) involved in the uptake of sulfur (S) as sulfate in pigeonpea following single inoculation of two sulfur-oxidizing bacteria (SOB), Stenotrophomonas maltophilia and Stenotrophomonas pavanii in the treatments amended with either elemental sulfur (S0) or sulfate (S6). Colonization potential and biofilm formation were analyzed through confocal laser scanning microscope (CLSM) and scanning electron microscope (SEM). Furthermore, the effect of seed inoculation on root architecture, expression of genes involved in sulfur oxidation (sox) in bacterial inoculants, and genes involved in sulfate transport in pigeonpea (PpSULTR) were analyzed to correlate with the higher uptake of S in roots and shoots of pigeonpea. Both the SOB exhibited a good colonization potential and biofilm formation on the roots of pigeonpea. Among the 11 sox genes targeted in rhizosphere of pigeonpea, expression was achieved for seven genes, which showed 2-fold increase in treatments inoculated with S. maltophilia and amended with either S6 or S0. The inoculation of S. maltophilia and amendment of S0 led to increased expression of PpSULTR genes by several folds in roots. The inoculation of SOB had a significant influence on non-enzymatic (osmolytes like proline) and enzymatic (PAL, peroxidase, superoxide dismutase, and catalase) levels. The results revealed a significant increase in sulfur uptake in roots and shoots in treatment inoculated with S. maltophilia and amended with S6. The investigation showed that the SOB-mediated over-expression of PpSULTR genes in roots of pigeonpea and sox genes in the rhizosphere were acting synergistically in facilitating higher uptake and translocation of S in roots and shoots of pigeonpea plants.

A Comparative Analysis of Microbe-Based Technologies Developed at ICAR-NBAIM Against Erysiphe necator Causing Powdery Mildew Disease in Grapes (Vitis vinifera L.).

Globally, Erysiphe necator causing powdery mildew disease in grapevines (Vitis vinifera L.) is the second most important endemic disease, causing huge economic losses every year. At present, the management of powdery mildew in grapes is largely dependent upon the use of chemical fungicides. Grapes are being considered as one of the high pesticide-demanding crops. Looking at the residual impact of toxic chemical pesticides on the environment, animal, and human health, microbe-based strategies for control of powdery mildew is an emerging technique. It offers an environment-friendly, residue-free, and effective yet safer approach to control powdery mildew disease in grapes. The mode of action is relatively diverse as well as specific to different pathosystems. Hence, the aim of this study was to evaluate the microbe-based technologies, i.e., Eco-pesticide®, Bio-Pulse®, and Bio-Care 24® developed at the Plant-Microbe Interaction and Rhizosphere Biology Lab, ICAR-NBAIM, Kushmaur, against grape powdery mildew and to integrate these technologies with a safer fungicide (sulfur) to achieve better disease control under organic systems of viticulture. The experiments were conducted at four different locations, namely, the vineyards of ICAR-NRCG, Rajya Draksha Bagayatdar Sangh (MRDBS), and two farmers' fields at Narayangaon and Junnar in the Pune district of Maharashtra. A significantly lower percent disease index (PDI) was recorded on the leaves of grape plants treated with Eco-Pesticide®/sulfur (22.37) followed by Bio-Pulse®/sulfur (22.62) and Bio-Care 24®/sulfur (24.62) at NRCG. A similar trend was observed with the lowest PDI on bunches of Eco-pesticide® /sulfur-treated plants (24.71) followed by Bio-Pulse®/sulfur (24.94) and Bio-Care®/sulfur (26.77). The application of microbial inoculants singly or in combination with sulfur has a significant positive impact on the qualitative parameters such as pH, total soluble solids (TSS), acidity, berry diameter, and berry length of the grapes at different locations. Among all the treatments, the Bio-Pulse®/sulfur treatment showed the highest yield per vine (15.02 kg), which was on par with the treatment Eco-Pesticide®/sulfur (14.94). When compared with the yield obtained from the untreated control, 2.5 to 3 times more yield was recorded in the plants treated with either of the biopesticides used in combination with sulfur. Even in the case of individual inoculation, the yield per vine was approximately two times higher than the untreated control and water-treated plants across the test locations. Results suggested that microbial technologies not only protect grapevines from powdery mildew but also enhance the quality parameters with increased yield across the test locations.

Modulation in Biofertilization and Biofortification of Wheat Crop by Inoculation of Zinc-Solubilizing Rhizobacteria.

Zinc is an important micronutrient needed for the optimum growth and development of plants. Contrary to chemical zinc fertilizers, the use of zinc-solubilizing bacteria is an environmentally friendly option for zinc enrichment in edible parts of crops. This study was conducted with the objective of selecting potential zinc-solubilizing rhizobacteria from the rhizosphere of chickpea grown in soils of eastern Uttar Pradesh and further assessing their impact on the magnitude of zinc assimilation in wheat crops. Among 15 isolates, CRS-9, CRS-17, CRS-30, and CRS-38 produced net soluble zinc in broth to the tune of 6.1, 5.9, 5.63, and 5.6 µg ml-1, respectively, in zinc phosphate with the corresponding pH of 4.48, 5.31, 5.2, and 4.76. However, the bacterial strains CRS-17, CRS-30, CRS-38, and CRS-9 showed maximum zinc phosphate solubilization efficiency of 427.79, 317.39, 253.57, and 237.04%, respectively. The four bacterial isolates were identified as Bacillus glycinifermentans CRS-9, Microbacterium oxydans CRS-17, Paenarthrobacter nicotinovorans CRS-30, and Bacillus tequilensis CRS-38 on the basis of morphological and biochemical studies and 16S rRNA gene sequencing. Bacterial inoculants significantly colonized the roots of wheat plants and formed a biofilm in the root matrix. These strains significantly increased seed germination (%) and vigor indices in wheat grown under glasshouse conditions. After 30 days of sowing of wheat under microcosm conditions, eight zinc transporter (TaZIP) genes were expressed maximally in roots, with concomitant accumulation of higher zinc content in the bacterially treated plant compared to the absolute control. Out of the four strains tested, two bacteria, B. tequilensis CRS-38 and P. nicotinovorans CRS-30, improved seed germination (%), vigor indices (2-2.5 folds), plant biomass, grain yield (2.39 g plant-1), and biofortificated grains (54.25 µg g-1Zn) of wheat. To the best of our knowledge, this may be the first report on the presence of zinc solubilization trait in B. glycinifermentans CRS-9, M. oxydans CRS-17, and P. nicotinovorans CRS-30.

Linking Soil Microbial Diversity to Modern Agriculture Practices: A Review.

Agriculture is a multifarious interface between plants and associated microorganisms. In contemporary agriculture, emphasis is being given to environmentally friendly approaches, particularly in developing countries, to enhance sustainability of the system with the least negative effects on produce quality and quantity. Modern agricultural practices such as extensive tillage, the use of harmful agrochemicals, mono-cropping, etc. have been found to influence soil microbial community structure and soil sustainability. On the other hand, the question of feeding the ever-growing global population while ensuring system sustainability largely remains unanswered. Agriculturally important microorganisms are envisaged to play important roles in various measures to raise a healthy and remunerative crop, including integrated nutrient management, as well as disease and pest management to cut down agrochemicals without compromising the agricultural production. These beneficial microorganisms seem to have every potential to provide an alternative opportunity to overcome the ill effects of various components of traditional agriculture being practiced by and large. Despite an increased awareness of the importance of organically produced food, farmers in developing countries still tend to apply inorganic chemical fertilizers and toxic chemical pesticides beyond the recommended doses. Nutrient uptake enhancement, biocontrol of pests and diseases using microbial inoculants may replace/reduce agrochemicals in agricultural production system. The present review aims to examine and discuss the shift in microbial population structure due to current agricultural practices and focuses on the development of a sustainable agricultural system employing the tremendous untapped potential of the microbial world.

An updated patent review on drugs for the treatment of tuberculosis (2018-present).

INTRODUCTION: Tuberculosis (TB) caused by Mycobacterium tuberculosis (M.tb) has been a global challenge as 1.4 million deaths were reported in 2019, which included deaths attributed to HIV-TB co-infection. It is curable by the prescribed Directly Observed Treatment Short (DOTS) course, but the situation becomes critical and alarming due to multi-drug resistant (MDR) and extensively drug-resistant (XDR) tuberculosis. Hence there has been an urgent need to develop novel M.tb chemotherapeutics to overcome this situation. AREAS COVERED: This review provides an overview and update on recent developments on the novel therapeutics for the treatment of TB from the important published and granted patents (2018-present). EXPERT OPINION: The discovery of potent chemotherapeutics with reduced toxicity to combat M.tb particularly MDR and XDR-TB is a major challenge in antitubercular drug development. The missing of any doses during the DOTS treatment and poor immunity particularly in HIV patients has been a major cause for the development of drug resistance. Hence the major focus has to be on novel targets with their inhibitors and novel molecules both of natural and synthetic origins along with repurposed drugs for the complete eradication of tuberculosis.

Inter-Genera Colonization of Ocimum tenuiflorum Endophytes in Tomato and Their Complementary Effects on Na+/K+ Balance, Oxidative Stress Regulation, and Root Architecture Under Elevated Soil Salinity.

Endophytic bacilli of ethano-botanical plant Ocimum tenuiflorum were screened for salt stress-alleviating traits in tomato. Four promising O. tenuiflorum endophytes (Bacillus safensis BTL5, Bacillus haynesii GTR8, Bacillus paralicheniformis GTR11, and Bacillus altitudinis GTS16) were used in this study. Confocal scanning laser microscopic studies revealed the inter-genera colonization of O. tenuiflorum endophytes in tomato plants, giving insights for widening the applicability of potential endophytes to other crops. Furthermore, in a pot trial under 150 mM NaCl concentration, the inoculated endophytes contributed in reducing salt toxicity and improving recovery from salt-induced oxidative stress by different mechanisms. Reduction in reactive oxygen species (ROS) (sub-cellular H2O2 and superoxide) accumulation was observed besides lowering programmed cell death and increasing chlorophyll content. Endophyte inoculation supplemented the plant antioxidant enzyme system via the modulation of enzymatic antioxidants, viz., peroxidase, ascorbate peroxidase, superoxide dismutase, and catalase, apart from increasing proline and total phenolics. Antioxidants like proline have dual roles of antioxidants and osmoregulation, which might also have contributed to improved water relation under elevated salinity. Root architecture, viz., root length, projection area, surface area, average diameter, tips, forks, crossings, and the number of links, was improved upon inoculation, indicating healthy root growth and enhanced nutrient flow and water homeostasis. Regulation of Na+/K+ balance and water homeostasis in the plants were also evident from the modulation in the expression of abiotic stress-responsive genes, viz., LKT1, NHX1, SOS1, LePIP2, SlERF16, and SlWRKY39. Shoot tissues staining with light-excitable Na+ indicator Sodium GreenTM Tetra (tetramethylammonium) salt showed low sodium transport and accumulation in endophyte-inoculated plants. All four endophytes exhibited different mechanisms for stress alleviation and indicated complementary effects on plant growth. Furthermore, this could be harnessed in the form of a consortium for salt stress alleviation. The present study established inter-genera colonization of O. tenuiflorum endophytes in tomato and revealed its potential in maintaining Na+/K+ balance, reducing ROS, and improving root architecture under elevated salinity.

Characterization and low-cost preservation of Chromobacterium violaceum strain TRFM-24 isolated from Tripura state, India.

BACKGROUND: Chromobacterium species, through their bioactive molecules, help in combating biotic and abiotic stresses in plants and humans. The present study was aimed to identify, characterize and preserve in natural gums the violet-pigmented bacterial isolate TRFM-24 recovered from the rhizosphere soil of rice collected from Tripura state. RESULTS: Based on morphological, biochemical and 16S rRNA gene sequencing, the isolate TFRM-24 was identified as Chromobacterium violaceum (NAIMCC-B-02276; MCC 4212). The bacterium is saprophytic, free living and Gram negative. The strain was found positive for production of IAA, cellulase, xylanase and protease, and showed tolerance to salt (2.5%) and drought (-1.2 MPa). However, it showed poor biocontrol activity against soil-borne phytopathogens and nutrient-solubilizing abilitiets. C. violaceum strain TRFM-24 did not survive on tryptic soya agar (TSA) beyond 12 days between 4 and 32 °C temperature hence a method of preservation of this bacterium was attempted using different natural gums namely Acacia nilotica (babul), Anogeissus latifolia (dhavda), Boswellia serrata (salai) and Butea monosperma (palash) under different temperature regime (6-32 °C). The bacterium survived in babul gum (gum acacia), dhavda and salai solution at room temperature beyond a year. CONCLUSION: Based on polyphasic approach, a violet-pigmented isolate TRFM-24 was identified as Chromobacterim violaceum which possessed some attributes of plant and human importance. Further, a simple and low-cost preservation method of strain TRFM-24 at room temperature was developed using natural gums such as babul, dhavda and salai gums which may be the first report to our knowledge.

Salt-Tolerant Compatible Microbial Inoculants Modulate Physio-Biochemical Responses Enhance Plant Growth, Zn Biofortification and Yield of Wheat Grown in Saline-Sodic Soil.

A wide range of root-associated mutualistic microorganisms have been successfully applied and documented in the past for growth promotion, biofertilization, biofortification and biotic and abiotic stress amelioration in major crops. These microorganisms include nitrogen fixers, nutrient mobilizers, bio-remediators and bio-control agents. The present study aimed to demonstrate the impact of salt-tolerant compatible microbial inoculants on plant growth; Zn biofortification and yield of wheat (Triticum aestivum L.) crops grown in saline-sodic soil and insight of the mechanisms involved therein are being shared through this paper. Field experiments were conducted to evaluate the effects of Trichoderma harzianum UBSTH-501 and Bacillus amyloliquefaciens B-16 on wheat grown in saline-sodic soil at Research Farm, ICAR-Indian Institute of Seed Sciences, Kushmaur, India. The population of rhizosphere-associated microorganisms changed dramatically upon inoculation of the test microbes in the wheat rhizosphere. The co-inoculation induced a significant accumulation of proline and total soluble sugar in wheat at 30, 60, 90 and 120 days after sowing as compared to the uninoculated control. Upon quantitative estimation of organic solutes and antioxidant enzymes, these were found to have increased significantly in co-inoculated plants under salt-stressed conditions. The application of microbial inoculants enhanced the salt tolerance level significantly in wheat plants grown in saline-sodic soil. A significant increase in the uptake and translocation of potassium (K+) and calcium (Ca2+) was observed in wheat co-inoculated with the microbial inoculants, while a significant reduction in sodium (Na+) content was recorded in plants treated with both the bio-agents when compared with the respective uninoculated control plants. Results clearly indicated that significantly higher expression of TaHKT-1 and TaNHX1 in the roots enhances salt tolerance effectively by maintaining the Na+/K+ balance in the plant tissue. It was also observed that co-inoculation of the test inoculants increased the expression of ZIP transporters (2-3.5-folds) which ultimately led to increased biofortification of Zn in wheat grown in saline-sodic soil. Results suggested that co-inoculation of T. harzianum UBSTH-501 and B. amyloliquefaciens B-16 not only increased plant growth but also improved total grain yield along with a reduction in seedling mortality in the early stages of crop growth. In general, the present investigation demonstrated the feasibility of using salt-tolerant rhizosphere microbes for plant growth promotion and provides insights into plant-microbe interactions to ameliorate salt stress and increase Zn bio-fortification in wheat.

Exploring Spike Protein as Potential Target of Novel Coronavirus and to Inhibit the Viability Utilizing Natural Agents.

BACKGROUND: By the end of 2019, the sudden outbreak of the novel coronavirus disease (COVID-19) has become a global threat. It is called COVID-19 because it was caused by the novel coronavirus (SARS-COV-2) in 2019. A total of 1.9 M deaths and 87.9 M cases have been reported all over the world, where 49M cases have recovered so far. Scientists are working hard to find chemotherapeutics and vaccines for COVID-19. Mutations in SARS-CoV-2 have been observed in a combination of several hazardous stresses, making them more resistant and beneficial. So to break down the viral system, the disease targets are examined. OBJECTIVE: In today's review, a comprehensive study of spike protein explains the main purpose of the novel coronavirus and how to prevent the spread of the disease virus cross-transmission from infected to a healthy person. METHODS: Covid-19 has already been declared a pandemic by the World Health Organization (WHO) due to its result in causing death and severe illness globally. SARS-CoV-2 is highly contagious; however, the intermediate host of the novel coronavirus is not clear. To explore the mechanisms of disease, one of the viral targets, such as the spike protein that binds to human cells and causes the disease by altering its genetic structure which is considered along with potential inhibitors. RESULTS: It has been shown that the interaction of receptor-binding domain (RBD) protein of SARS- CoV-2 spike and the angiotensin-converting enzyme 2 (ACE2) host receptor and further replication of coronavirus spike protein causes its invasion in the host cell. The human Lymphocyte antigen 6 complex, Locus E (LY6E), inhibits the entry of CoV into host cells by interfering with the human gene, inducing spike protein-mediated membrane fusion. Some natural formulations have also been shown to prevent spike protein from binding to the host cell. CONCLUSION: With the development of the LY6E gene activator that can inhibit spike protein- ACE2-mediated membrane fusion, new opportunities for SARS-CoV-2 treatment may emerge. Existing antiviral fusion inhibitors and natural compounds targeting spike resistance can serve as a template for further SARS-CoV-2 drug formulation.

Efficiency of Homology Modeling Assisted Molecular Docking in G-protein Coupled Receptors.

BACKGROUND: Molecular docking is in regular practice to assess ligand affinity on a target protein crystal structure. In the absence of protein crystal structure, the homology modeling or comparative modeling is the best alternative to elucidate the relationship details between a ligand and protein at the molecular level. The development of accurate homology modeling (HM) and its integration with molecular docking (MD) is essential for successful, rational drug discovery. OBJECTIVE: The G-protein coupled receptors (GPCRs) are attractive therapeutic targets due to their immense role in human pharmacology. The GPCRs are membrane-bound proteins with the complex constitution, and the understanding of their activation and inactivation mechanisms is quite challenging. Over the past decade, there has been a rapid expansion in the number of solved G-protein-coupled receptor (GPCR) crystal structures; however, the majority of the GPCR structures remain unsolved. In this context, HM guided MD has been widely used for structure-based drug design (SBDD) of GPCRs. METHODS: The focus of this review is on the recent (i) developments on HM supported GPCR drug discovery in the absence of GPCR crystal structures and (ii) application of HM in understanding the ligand interactions at the binding site, virtual screening, determining receptor subtype selectivity and receptor behaviour in comparison with GPCR crystal structures. RESULTS: The HM in GPCRs has been extremely challenging due to the scarcity in template structures. In such a scenario, it is difficult to get accurate HM that can facilitate understanding of the ligand-receptor interactions. This problem has been alleviated to some extent by developing refined HM based on incorporating active /inactive ligand information and inducing protein flexibility. In some cases, HM proteins were found to outscore crystal structures. CONCLUSION: The developments in HM have been highly operative to gain insights about the ligand interaction at the binding site and receptor functioning at the molecular level. Thus, HM guided molecular docking may be useful for rational drug discovery for the GPCRs mediated diseases.

ATP Synthase Inhibitors as Anti-tubercular Agents: QSAR Studies in Novel Substituted Quinolines.

BACKGROUND: Tuberculosis (TB) is a major infectious disease caused by Mycobacterium Tuberculosis. As per the World Health Organization (WHO) report of 2019, there were 1.5 million deaths in the year 2018, mainly because of multi- and extensively drug-resistant tuberculosis (MDR & XDR-TB). Among several antitubercular drugs in clinical trials, bedaquiline (TMC207) is a highly promising drug that was approved by the FDA in 2012 and marketed in 2016 for the treatment of multidrug resistant TB in combination with other drugs. Bedaquiline acts on mycobacterial ATP synthase and is highly effective in replicating as well as on dormant mycobacteria. Several series of substituted quinolines have been reported with their antitubercular and ATP synthase inhibitory activity. METHODS: To understand the role of physicochemical parameters like hydrophobicity, electronic and steric factors in eliciting the biological response, the Quantitative structure-activity relationship (QSAR) studies have been carried out using the computed parameters as independent variable and activity (-log IC50/MIC) as the dependent variable. RESULTS: The developed QSAR models in terms of positively contributing Molar Refractivity (MR) and negatively contributing Partition Coefficient (PC) and Connolly Molecular Area (CMA) parameters have high predictivity as also shown on external data set and the mean value of the computed 3D parameters of enantiomers may be used in QSAR analysis for racemic compounds. CONCLUSION: These results are also substantiated by pharmacophore modeling. The similar dependence of antitubercular activity against whole-cell M.Tb.H37Rv on MR and CMA suggests ATP synthase as the main target for antitubercular activity and the QSAR models may be useful in the identification of novel antitubercular agents.

Recent Breakthroughs in Various Antimicrobial Resistance Induced Quorum Sensing Biosynthetic Pathway Mediated Targets and Design of their Inhibitors.

OBJECTIVE: The world is under the grasp of dangerous post-antibiotics and antimicrobials attack where common infections may become untreatable, leading to premature deaths due to antimicrobial resistance (AMR). While an estimated 7,00,000 people die annually due to AMR, which is a public health threat to all communities in different parts of the world regardless of their economic status; however, this threat is serious in low- and middle-income countries having lack of sanitation and health infrastructure. The 68th World Health Assembly endorsed the Global Action Plan on antimicrobial resistance. Consequently, many countries started drafting and committing to National Action Plans against AMR. As strong as National Action Plans are in terms of prescribing rational use of antimicrobials, infection control practices, and related public health measures, without strong healthcare systems, these measures will have a limited impact on AMR in developing countries. METHODS: The major reason for AMR is microbial quorum sensing (QS) that may strengthen the microbial community to generate inter-communication and virulence effects via quorum sensing mechanisms. Global stewardship to combat antimicrobial resistance aims to develop anti-quorum sensing compounds that can inhibit the biosynthetic pathway mediated different quorum sensing targets. RESULTS: It may pave an effective attempt to minimize microbial quorum sensing mediated antimicrobial resistance. The present review describes QS mediated various potential target enzymes, their connection to AMR, and finds out the corresponding QS biosynthetic target inhibitors. CONCLUSION: These potential inhibitors can be derivatized to design and develop next-generation antimicrobial agents.

Sustainable use of the spent mushroom substrate of Pleurotus florida for production of lignocellulolytic enzymes.

Spent mushroom substrate (SMS), a major byproduct of the mushroom industry, is a lignocellulosic biomass, which contains approximately 57-74.3% of holocellulose fraction. This study was aimed at utilizing SMS of Pleurotus florida for recovery of lignocellulolytic enzymes and sugars and also as a substrate for production of cellulolytic enzymes using different isolates of Trichoderma and Aspergillus under solid-state fermentation (SSF). SMS of P. florida extracts contained significant amounts of laccase (3,015.8 ± 29.5 U/g SMS) and xylanase (1,187.9 ± 12 U/g SMS) activity. Crystallinity pattern and chemical changes in SMS revealed that SMS had a lower crystallinity index (34.2%) as compared with the raw biomass (37.8%), which, in turn, helps in enhancing the accessibility of cellulolytic enzymes to holocellulose. Among the isolates, Trichoderma longibrachiatum A-01 showed maximum activity of endoglucanase (220.4 ± 5.9 U/mg), exoglucanase (78.5 ± 3.2 U/mg) and xylanase (1,550.4 ± 11.6 U/mg) while Aspergillus aculeatus C-08 showed maximum activity of cellobiase (113.9 ± 3.9 U/mg). Extraction with sodium citrate buffer (pH 4.8) showed maximum cellulolytic enzyme activity as compared with other solvents tested. Partial purification of endoglucanase, exoglucanase, xylanase, and cellobiase resulted in 56.3% (1,112.5 U/mg), 48.4% (212.5 U/mg), 44% (4,492.3 U/mg), and 62% (705.0 U/mg) yield with an increase by 5.2-, 4.5-, 4.1-, and 5.0-fold as compared with crude extract. The results reveal that SMS from P. florida could be a potential and cost-effective substrate for production of cellulolytic enzymes from T. longibrachiatum A-01 and A. aculeatus C-08.

Restructuring the Cellular Responses: Connecting Microbial Intervention With Ecological Fitness and Adaptiveness to the Maize (Zea mays L.) Grown in Saline-Sodic Soil.

Salt stress hampers plant growth and development. It is now becoming one of the most important threats to agricultural productivity. Rhizosphere microorganisms play key roles in modulating cellular responses and enable plant tolerant to salt stress, but the detailed mechanisms of how this occurs need in-depth investigation. The present study elucidated that the microbe-mediated restructuring of the cellular responses leads to ecological fitness and adaptiveness to the maize (Zea mays L.) grown in saline-sodic soil. In the present study, effects of seed biopriming with B. safensis MF-01, B. altitudinis MF-15, and B. velezensis MF-08 singly and in consortium on different growth parameters were recorded. Soil biochemical and enzymatic analyses were performed. The activity and gene expression of High-Affinity K+ Transporter (ZmHKT-1), Sodium/Hydrogen exchanger 1 (zmNHX1), and antioxidant enzymes (ZmAPX1.2, ZmBADH-1, ZmCAT, ZmMPK5, ZmMPK7, and ZmCPK11) were studied. The expression of genes related to lateral root development (ZmHO-1, ZmGSL-1, and ZmGSL-3) and root architecture were also carried out. Seeds bioprimed with consortium of all three strains have been shown to confer increased seed germination (23.34-26.31%) and vigor indices (vigor index I: 38.71-53.68% and vigor index II: 74.11-82.43%) as compared to untreated control plant grown in saline-sodic soil at 30 days of sowing. Results indicated that plants treated with consortium of three strains induced early production of adventitious roots (tips: 4889.29, forks: 7951.57, and crossings: 2296.45) in maize compared to plants primed with single strains and untreated control (tips: 2019.25, forks: 3021.45, and crossings: 388.36), which was further confirmed by assessing the transcript level of ZmHO-1 (7.20 folds), ZmGSL-1 (4.50 folds), and ZmGSL-3 (12.00 folds) genes using the qPCR approach. The uptake and translocation of Na+, K+, and Ca2+ significantly varied in the plants treated with bioagents alone or in consortium. qRT-PCR analysis also revealed that the ZmHKT-1 and zmNHX1 expression levels varied significantly in the maize root upon inoculation and showed a 6- to 11-fold increase in the plants bioprimed with all the three strains in combination. Further, the activity and gene expression levels of antioxidant enzymes were significantly higher in the leaves of maize subjected seed biopriming with bioagents individually or in combination (3.50- to 12.00-fold). Our research indicated that ZmHKT-1 and zmNHX1 expression could effectively enhance salt tolerance by maintaining an optimal Na+/K+ balance and increasing the antioxidant activity that keeps reactive oxygen species at a low accumulation level. Interestingly, up-regulation of ZmHKT-1, NHX1, ZmHO-1, ZmGSL-1, and ZmGSL-3 and genes encoding antioxidants regulates the cellular responses that could effectively enhance the adaptiveness and ultimately leads to better plant growth and grain production in the maize crop grown in saline-sodic soil.

Synthesis, SAR and docking studies of substituted aryl phenylthiazolyl phenylcarboxamide as potential protein tyrosine phosphatase 1B (PTP1B) inhibitors.

In our continued effort to discover novel PTP1B inhibitor with improved in vivo activity, we attempted to optimize our previously discovered lead compound by replacing the sulfonyl group with benzoyl group to yield compound II. Additional structural modifications were performed on compound II to yield a series of 24 aryl phenylthiazolyl phenylcarboxamides as potential PTP1B inhibitors. Of the 24 tested, 6 compounds showed good PTP1B inhibitory activity while compound 38 as the most promising one. The plausible PTP1B-binding site interaction of compound 38 showed favourable binding similar to known PTP1B binders and suggests its selectivity towards PTP1B. Compound 38 also showed promising antihyperglycaemic, antidyslipidaemic and insulin resistant reversal activities in vivo in STZ model and db/db mice model. Altogether, the compound 38 presents an excellent candidate for future PTP1B targeted drug discovery.

Lipid Lowering Oxopropanylindole Hydrazone Derivatives with Antioxidant and Anti-hyperglycemic Activity.

A series of substituted oxopropanylindole hydrazone derivatives was synthesized and evaluated for anti-oxidant and anti-dyslipidemic activity. Of the 12 tested, 3 compounds (6c, 7b and 7d) showed good anti-oxidant activity, compound 6c attenuated LDL oxidation by 32%. The compounds 6c and 7d also showed good anti-dyslipidemic activity by reducing serum levels of total cholesterol (TC), phospholipids (PL) and triglycerides (TG). These two compounds were further evaluated for antiadipogenic and anti-hyperglycemic activity, where 6c showed 44% reduction in lipid accumulation and 20.5% and 24.3% reduction in blood glucose at 5h and 24h respectively, as compared to standard drug metformin. Thus, compounds 6c and 7d with balanced anti-oxidant and anti-dyslipidimic activities may be excellent candidates for lead optimization and drug development for the treatment of metabolic disorders.

Application of Docking Analysis in the Prediction and Biological Evaluation of the Lipoxygenase Inhibitory Action of Thiazolyl Derivatives of Mycophenolic Acid.

5-LOX inhibition is among the desired characteristics of anti-inflammatory drugs, while 15-LOX has also been considered as a drug target. Similarity in inhibition behavior between soybean LOX-1 and human 5-LOX has been observed and soybean LOX (sLOX) type 1b has been used for the evaluation of LOX inhibition in drug screening for years. After prediction of LOX inhibition by PASS and docking as well as toxicity by PROTOX and ToxPredict sixteen (E)-N-(thiazol-2-yl)-6-(4-hydroxy-6-methoxy-7-methyl-3-oxo-1,3-dihydroisobenzofuran-5-yl)-4-methylhex-4-enamide derivatives with lengths varying from about 15⁻20 Å were evaluated in vitro for LOX inhibitory action using the soybean lipoxygenase sLOX 1b. Docking analysis was performed using soybean LOX L-1 (1YGE), soybean LOX-3 (1JNQ), human 5-LOX (3O8Y and 3V99) and mammalian 15-LOX (1LOX) structures. Different dimensions of target center and docking boxes and a cavity prediction algorithm were used. The compounds exhibited inhibitory action between 2.5 µΜ and 165 µΜ. Substituents with an electronegative atom at two-bond proximity to position 4 of the thiazole led to enhanced activity. Docking results indicated that the LOX structures 1JNQ, 3V99 and 1LOX can effectively be used for estimation of LOX inhibition and amino acid interactions of these compounds.

Halotolerant Exiguobacterium profundum PHM11 Tolerate Salinity by Accumulating L-Proline and Fine-Tuning Gene Expression Profiles of Related Metabolic Pathways.

Salinity stress is one of the serious factors, limiting production of major agricultural crops; especially, in sodic soils. A number of approaches are being applied to mitigate the salt-induced adverse effects in agricultural crops through implying different halotolerant microbes. In this aspect, a halotolerant, Exiguobacterium profundum PHM11 was evaluated under eight different salinity regimes; 100, 250, 500, 1000, 1500, 2000, 2500, and 3000 mM to know its inherent salt tolerance limits and salt-induced consequences affecting its natural metabolism. Based on the stoichiometric growth kinetics; 100 and 1500 mM concentrations were selected as optimal and minimal performance limits for PHM11. To know, how salt stress affects the expression profiles of regulatory genes of its key metabolic pathways, and total production of important metabolites; biomass, carotenoids, beta-carotene production, IAA and proline contents, and expression profiles of key genes affecting the protein folding, structural adaptations, transportation across the cell membrane, stress tolerance, carotenoids, IAA and mannitol production in PHM11 were studied under 100 and 1500 mM salinity. E. profundum PHM11 showed maximum and minimum growth, biomass and metabolite production at 100 and 1500 mM salinity respectively. Salt-induced fine-tuning of expression profiles of key genes of stress pathways was determined in halotolerant bacterium PHM11.

Pharmacological evaluation of the efficacy of Dysoxylum binectariferum stem bark and its active constituent rohitukine in regulation of dyslipidemia in rats.

The antidyslipidemic effect of the ethanolic extract of Dysoxylum binectariferum stem bark and its major active constituent rohitukine was evaluated in a high fat diet (HFD)-fed dyslipidemic rat model. Chronic feeding of ethanolic extract (200 mg/kg) in HFD-fed rats showed significant lipid lowering activity. The bioassay guided fractionation of ethanolic extract resulted in the identification of known alkaloid rohitukine as major active constituent. Rohitukine (50 mg/kg) significantly decreased the plasma levels of total cholesterol (24 %), phospholipids (25 %), triglycerides (27 %), very low density lipoprotein (27 %) and low density lipoprotein (32 %) accompanied with an increase in high density lipoprotein (21 %). The present study demonstrated that ethanolic extract of Dysoxylum binectariferum stem bark and its major constituent rohitukine both have antidyslipidemic as well as antioxidant potentials. The antidyslipidemic activity of rohitukine can be correlated to its effect on enzymes involved in lipid metabolism.