Phytochemical Screening, Quantification, FT-IR Analysis, and In Silico Characterization of Potential Bio-active Compounds Identified in HR-LC/MS Analysis of the Polyherbal Formulation from Northeast India.

Diabetes is a group of metabolic disorders characterized by elevated blood sugar levels, leading to many undesirable health consequences. There are many herbal formulations, traditionally used by the Northeast Indian population for disease management. These formulations require scientific validations to optimize their efficacy and increase their popularity. In this study, we attempt to scientifically validate a polyherbal formulation traditionally used for the management of diabetes through preliminary phytochemicals investigation, characterization of potential phytochemicals using Fourier transform infrared (FT-IR) spectroscopy, high-resolution liquid chromatography mass spectrometry (HR-LC/MS) analysis, and in silico characterization of physiochemical, drug-likeness, and pharmacokinetic properties of identified phytochemical compounds. Qualitative phytochemical screening of various extracts of the formulation confirmed the presence of alkaloids, phenols and tannins, flavonoids, fats, and oils. Phytochemical quantification of the various extracts showed that the highest total phenolic content is present in the ethanolic extract (35.61 ± 0.15 mg GAE/g), while the highest total flavonoid content is present in the chloroform extract (76.33 ± 2.96 mg QE/g) of the formulation. FT-IR spectroscopic analysis revealed various characteristic band values with various functional groups in the formulation extract such as amines, alcohol, fluoro compounds, phenol, alkane, alkene, and conjugated acid groups. HR-LC/MS analyses identified nearly 51 compounds including 9 small peptides and 42 potential phytochemical compounds. In silico SwissADME analysis of identified compounds revealed 25 potential compounds following Lipinski's rule and showing drug-like characteristics, and out of them, 16 compounds exhibited good oral bioavailability, as revealed in the bioavailability radar. The overall study showed that the presented polyherbal formulation is enriched with bio-active phytochemical compounds with good pharmaceutical values.

Kinetics and Production of Rhamnolipid from Pseudomonas sp. TMB2 in Shake-Flask and Fabricated Batch Reactor.

Rhamnolipid producing Pseudomonas sp. TMB2 was selected for this investigation to optimize the metabolite production in fabricated batch reactor after studying yield kinetics in shake-flask and tried to reduce the overall production cost through In-situ recovery technology. Using various kinetic models, maximum specific growth rate (µmax) and half velocity constant (KS) of TMB2 were determined to be 0.185 ± 0.0025 h-1 and 0.124 ± 0.024 g/L in shake-flask, respectively. Further, a batch reactor was designed with integration of a foam fractionate column in the lid of the vessel and their performances were compared with shake-flask studies. The yields of rhamnolipids production on biomass (YP/X), rhamnolipids production on substrate (YP/S) and biomass production on substrate (YX/S) were found to be higher in reactor than that of shake-flask. The best conditions for maximum rhamnolipid production in reactor were observed to be 2 vvm and 300 rpm, giving YP/S = 0.152 g/g, YP/X = 0.542 g/g and YX/S = 0.280 g/g. Rhamnolipid production was increased by ≈ 10.18% in the reactor than that of shake-flask in optimized conditions. Rhamnolipid concentrations in the foamate were also found to be higher than that of reactor vessels. Further, the performance of foam fractionation was validated through enrichment and recovery, which were found in the range of 2.75-4.86 and 25.33-64.64%, respectively. Supplementary Information: The online version contains supplementary material available at 10.1007/s12088-022-01021-0.

Characterization of Pseudomonas sp. TMB2 produced rhamnolipids for ex-situ microbial enhanced oil recovery.

The present study describes the ex-situ production of a biosurfactant by Pseudomonas sp. TMB2 for its potential application in enhancing oil recovery. The physicochemical parameters such as temperature and pH were optimized as 30 °C and 7.2, respectively, for their maximum laboratory scale production in mineral salt medium containing glucose and sodium nitrate as best carbon and nitrogen sources. The surface activity of the resulting culture broth was declined from 71.9 to 33.4 mN/m having the highest emulsification activity against kerosene oil. The extracted biosurfactant was characterized chemically as glycolipid by Fourier-transform infrared spectroscopy and 1H and 13C nuclear magnetic resonance spectroscopy analyses. The presence of mono-rhamnolipids (Rha-C8:2, Rha-C10, Rha-C10-C10, and Rha-C10-C12:1) and di-rhamnolipids (Rha-Rha-C12-C10, Rha-Rha-C10-C10, and Rha-Rha-C10-C12:1) congeners were determined by liquid chromatography-mass spectroscopy analysis. The thermostability and degradation pattern of the candidate biosurfactant were tested by thermogravimetry assay and differential scanning calorimetry studies for its suitability in ex-situ oil recovery technology. The rhamnolipid based slug, prepared in 4000 ppm brine solution reduced the interfacial tension between liquid paraffin oil and aqueous solution to 0.8 mN/m from 39.1 mN/m at critical micelle concentration of 120 mg/L. The flooding test was performed using conventional core plugs belonging to oil producing horizons of Upper Assam Basin and recovered 16.7% of original oil in place after secondary brine flooding with microscopic displacement efficiency of 27.11%.

Chitosan coated silk fibroin surface modified by atmospheric dielectric-barrier discharge (DBD) plasma: a mechanically robust drug release system.

The current study is designed to develop mechanically strong chitosan (Cs) coated silk based drug delivery system loaded with amoxicillin trihydrate (AMOX). For this purpose, surface modification of Antherarea assama silk fibroin (AASF) yarn is carried out using dielectric barrier discharge (DBD) oxygen (O2) plasma at atmospheric pressure followed by coating with drug incorporated Cs (AASF/O2/Cs-AMOX). It is observed that O2 plasma treatment results in altering surface chemistry and morphology of silk fibroin surface which subsequently improves mechanical properties of AASF/O2/Cs-AMOX yarn. The AASF/O2/Cs-AMOX yarn exhibits strong antibacterial activities against gram-positive Staphylococcus aureus and gram-negative Escherichia coli bacteria. In vitro drug release profile reveals biphasic release behavior of AASF/O2/Cs-AMOX yarn consisting of immediate followed by controlled and sustained release of AMOX up to the observation period of 168 hours. MTT cell viability study further reveals that O2 plasma treatment and incorporation of AMOX do not have any adverse effect on cytocompatibility of AASF/O2/Cs-AMOX yarn. Together, all these results suggest that AASF/O2/Cs-AMOX yarn can be explored in treatment of bacterial infected wounds as potential surgical suture.

Optimization and characterization of a glycolipid produced by Achromobacter sp. to use in petroleum industries.

A biosurfactant, produced by Achromobacter sp. TMB1 is reported through this investigation having physiochemical properties useful for operational and remedial activities in petroleum industries. The strain isolated from soils of local petrol pumps when allowed to grow in glucose containing mineral salts media (MSM) in ambient environment that is, 30 °C and varying pH in between 5.5 and 7.2, showed surface tension reduction as low as 34.25 dyne cm-1 at an interval of 48-72 h. Taguchi experiment confirmed the contribution of glucose, yeast extracts, and NaNO3 concentration on biosurfactant production. FTIR and 1 H NMR analysis of culture supernatant obtained after acid precipitation and solvent extraction methods revealed the glycolipid nature of the extracted compounds. HR-LCMS study further revealed the presence of 10 different types of mono- and di-rhamnolipids congeners with the fatty acids carbon length C8-12 . The isolated biosurfactant shows functional stability in the temperature range 20-100 °C and pH range 2-12 while maintaining the structural integrity till 550 °C (TGA-DSC), strongly suggests its potential applications in petroleum industries.

Sonication assisted assemblage of exotic polymer supported nanostructured bio-hybrid system and prospective application.

This work was focused on sonication mediated immobilization of porcine pancreatic lipase (PPL) onto poly(ethylene glycol) supported silver-iron oxide hybrid nanoparticles (PEG-Ag/IONPs). Selected process parameters of sonication were optimized using response surface methodology. Sonication assisted assemblage of spherical PEG-Ag/IONPs and consequent evolution of nanorods post PPL immobilization were documented. The efficacy of the reported immobilization strategy was attested by the increased thermostability, storage stability and enhanced activity of the biocatalyst, suggestive of plausible structural modulations post immobilization. The commercial prospect of the antibacterial and magnetically recyclable system was vouched by its excellent compatibility with some commercial detergents for oil de-staining.