Methyl jasmonate inducible UGT79A18 is a novel glycosyltransferase involved in the bacoside biosynthetic pathway in Bacopa monnieri.

Bacosides are dammarane-type triterpenoidal saponins in Bacopa monnieri and have various pharmacological applications. All the bacosides are diversified from two isomers, i.e., jujubogenin and pseudojujubogenin. The biosynthetic pathway of bacoside is not well elucidated. In the present study, we characterized a UDP-glycosyltransferase, UGT79A18, involved in the glycosylation of pseudojujubogenin. UGT79A18 shows higher expression in response to 5 h of wounding, and 3 h of MeJA treatment. The recombinant UGT79A18 shows in vitro activity against a wide range of flavonoids and triterpenes and has a substrate preference for protopanaxadiol, a dammarane-type triterpene. Secondary metabolite analysis of overexpression and knockdown lines of UGT79A18 in B. monnieri identify bacopasaponin D, bacopaside II, bacopaside N2 and pseudojujubogenin glucosyl rhamnoside as the major bacosides that were differentially accumulated. In the overexpression lines of UGT79A18, we found 1.7-fold enhanced bacopaside II, 8-fold enhanced bacopasaponin D, 3-fold enhanced pseudojujubogenin glucosyl rhamnoside, and 1.6-fold enhanced bacopaside N2 content in comparison with vector control plant, whereas in the knockdown lines of UGT79A18, we found 1.4-fold reduction in bacopaside II content, 3-fold reduction in the bacopasaponin D content, 2-fold reduction in the pseudojujubogenin glucosyl rhamnoside content, and 1.5-fold reduction in bacopaside N2 content in comparison with vector control. These results suggest that UGT79A18 is a significant UDP glycosyltransferase involved in glycosylating pseudojujubogenin and enhancing the pseudojujubogenin-derived bacosides.

Chitosan-carbon nanofiber based disposable bioelectrode for electrochemical detection of oxytocin.

Bioelectrodes with low carbon footprint can provide an innovative solution to the surmounting levels of e-waste. Biodegradable polymers offer green and sustainable alternatives to synthetic materials. Here, a chitosan-carbon nanofiber (CNF) based membrane has been developed and functionalized for electrochemical sensing application. The surface characterization of the membrane revealed crystalline structure with uniform particle distribution, and surface area of 25.52 m2/g and pore volume of 0.0233 cm3/g. The membrane was functionalized to develop a bioelectrode for the detection of exogenous oxytocin in milk. Electrochemical impedance spectroscopy was employed to determine oxytocin in a linear concentration range of 10 to 105 ng/mL. The developed bioelectrode showed an LOD of 24.98 ± 11.37 pg/mL and sensitivity of 2.77 × 10-10 Ω / log ng mL-1/mm2 for oxytocin in milk samples with 90.85-113.34 percent recovery. The chitosan-CNF membrane is ecologically safe and opens new avenues for environment-friendly disposable materials for sensing applications.

Valorization of Ginger Waste-Derived Biochar for Simultaneous Multiclass Antibiotics Remediation in Aqueous Medium.

The presence of antibiotics in the aqueous environment has been a serious concern primarily due to the development of antimicrobial resistance (AMR) in diverse microbial populations. To overcome the rising AMR concerns, antibiotic decontamination of the environmental matrices may play a vital role. The present study investigates the use of zinc-activated ginger-waste derived biochar for the removal of six antibiotics belonging to three different classes, viz., ß-lactams, fluoroquinolones, and tetracyclines from the water matrix. The adsorption capacities of activated ginger biochar (AGB) for the concurrent removal of the tested antibiotics were investigated at different contact times, temperatures, pH values, and initial concentrations of the adsorbate and adsorbent doses. AGB demonstrated high adsorption capacities of 5.00, 17.42, 9.66, 9.24, 7.15, and 5.40 mg/g for amoxicillin, oxacillin, ciprofloxacin, enrofloxacin, chlortetracycline, and doxycycline, respectively. Further, among the employed isotherm models, the Langmuir model fitted well for all the antibiotics except oxacillin. The kinetic data of the adsorption experiments followed the pseudo-second order kinetics suggesting chemisorption as the preferred adsorption mechanism. Adsorption studies at different temperatures were conducted to obtain the thermodynamic characteristics suggesting a spontaneous exothermic adsorption phenomenon. AGB being a waste-derived cost-effective material shows promising antibiotic decontamination from the water environment.