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Current study discloses eco-friendly one pot robust method for the synthesis of silver nanoparticles by employing novel bark extract of the medicinal plant Terminalia bellerica Roxb. Synthesized silver nanoparticles (B-AgNPs) were found spherical and crystalline, as confirmed by UV–visible spectroscopy, XRD, TEM and FTIR. Catalytic potential of B-AgNPs was assessed by reductive degradation of various waste water pollutants, such as 4-nitrophenol, methyl orange, methylene blue and eosin yellow that fitted well to pseudo first order kinetics. B-AgNPs were found most efficient towards the reduction of 4-nitrophenol and removed 88.7% of it in 60 min. An artificial neural networks (ANNs) model based on experimental data was developed to describe the nonlinear behavior of the catalytic process that was found most accurate for the reductive degradation of eosin yellow. Antioxidant activity, evaluated by standard DPPH and ABTS assays, was dose dependent and B-AgNPs were found two fold potent in DPPH radical scavenging than the standard used. These results suggest that B-AgNPs could be a sustainable source of technological innovation in wastewater treatment and management of oxidative stress related health disorders.

In the present study, structurally diverse improvement was made towards bis(indolyl)methanes 5(a-e) and 5′(a-e) along with 6(a-e) and 6′(a-e) by multicomponent approach. Mono and di-N- substituted BIMs were formed by 2(a-e) and 2′(a-e), 3(a-e) and 3′(a-e). Silica-potassium hydrogen sulfate (SiO2-KHSO4) benign and efficient catalyst is used for the synthesis of new compounds where pre-modified indole unit was alkylated by substituted aromatic aldehydes. The yield was significantly affected in the presence of SiO2-KHSO4 and maximum yield (89% in 1 h reaction) of BIMs was achieved using SiO2-KHSO4 (mol 5%). The SiO2-KHSO4 also considerably reduced the reaction time for the synthesis of BIMs. This protocol was found to be beneficial with respect to catalyst, short reaction time, simple work-up and high yield. The compounds thus prepared are studied through FTIR, 1H NMR and MS spectral data.

Herein, we demonstrate a facile and green route for the synthesis of silver nanoparticles (AgNPs) from silver nitrate and seed extracts of different vegetable seeds of Brassicaceae family. All the nanocomposites were fully characterized in the solid-state via various techniques such UV–vis spectrophotometer (UV–Vis); x-ray diffraction (XRD), High-resolution transmission electron microscopy (HR-TEM), energy-dispersive x-ray spectroscopy (EDS), and Fourier transform infrared (FTIR) spectrometry. The experimental parameters such as variation in seeds extract concentration, temperature, stirring time and pH were noted and optimum condition of concentration (20 ml), temperature (80 °C) and pH 8.5 was selected for the synthesis of NPs. Optical absorbance of AgNPs at ≈425 nm indicated the formation of metallic silver through surface plasmon resonance. The successful capping of biological macromolecules was confirmed by FTIR spectroscopy. XRD pattern depicted the formation of face-centered cubic silver nano-composite with average crystal size ranges from ≈14–20 nm. Bio-synthesized Ag nanoparticles showed enhanced antibacterial potential against gram-positive (B. safensis, B. subtilis, B. pumilis and S. aureus) and negative gram (E. coli and S.typhi) strains by disc diffusion method. Highest antimicrobial activity was given by sample S3 (17 mm) against B. pumilis whereas, sample S2 and S5 also showed significant bactericidal potential against B. pumilis that is 15 mm. While highest zone of inhibition for sample S1 and S4 is 14 mm.

A series of fifteen novel gallic acid esters (7a-o) was synthesized and structure was confirmed by spectral data. Antibiotic power of compounds was assessed against a panel of ten microbes while antioxidant activity was gauged by employing DPPH, ABTS and antilipid peroxidation assays. It was found that in comparison to lead, many of the synthesized derivatives implied much improved broad spectrum antimicrobial effect. Most effective compound found was 7c specifically against resistant gram-negative strains such as P. aeruginosa, E. coli and E. aerogenes. Potent antioxidant capacity was exhibited by7a and 7d in electron transfer assays while 7j and 7c provided maximum shielding against lipid peroxidation. Structure-activity analysis revealed that analogues with electron -withdrawing substituent particularly chloro group stand out as much better antibiotic agent. This study suggests that halogenated gallic acid analogues might be promising pharmacological candidates in view of further drug development. This work is licensed under a Creative Commons Attribution 4.0 International License.

The ability of Arundo donax against chromium pollution was tested. A. donax plants were grown under greenhouse conditions in nutrient solution having Cr (0, 50, 100, 200, 400, 600, and 900 μg L −1 ) for three weeks. Shoots and roots dry matter production, growth parameters, plant physiological and morphological characters were measured. The maximum Cr content in roots was 206.33 μg g −1 . Likewise, Cr concentration in stem was 262.6 μg g −1 at 900 μg L −1 supplied Cr. In case of leaves, the maximum Cr concentration was 206.33 μg g −1 at 900 μg L −1 supplied Cr. The IC 50 values of antioxidants using ABTS and DPHH standards showed that both time and increasing Cr concentrations affected the production of antioxidants indicated by lower IC 50 value on 21st day. A. donax may be used in remediation of Cr contaminated wastewaters.

Emodinol, a new oleane type triterpene, has been isolated from the chloroform soluble fraction of Paeonia emodi. The structure 1beta, 3beta, 23-trihydroxyolean-12-en-28-oic acid 1 has been assigned on the basis of spectral studies including 2D NMR. It showed significant beta-glucuronidase inhibitory activity. In addition benzoic acid and 3-hydroxybenzoic acid have also been reported for the first time from this species.

Steam distilled oil of Cymbopogon citratus was analyzed by Gas Chromatographic-Mass Spectrometry (GC-MS) and citral was found as major constituent. The oil exhibited significant inhibition of beta-glucuronidase activity and also showed activities against some tested human, plant and animal pathogens. The minimum inhibitory concentrations could not be determined due to the lack of some chemicals.

Eight new beta-N-substituted acyl hydrazides along with their corresponding acyl derivatives were synthesized and screened for in vitro beta-glucuronidase inhibition and found to be active against the enzyme. All of these compounds were found to be noncompetitive inhibitors except for N'-(2-cyanoethyl)-4-hydroxy benzohydrazide (10), which was found to be an uncompetitive inhibitor. Structure-activity relationship studies indicated that the benzyloxy group present in compounds 12 and 13 is responsible for the beta-glucuronidase inhibition activity.

Pentacyclic triterpenes (1) and (2) have been isolated from Mimusops elengi and assigned structures 3beta,6beta,19alpha,23-tetrahydroxy-urs-12-ene and 1beta-hydroxy-3beta-hexanoyllup-20 (29)-ene-23, 28-dioic acid, respectively, on the basis of spectroscopic studies including 2D-NMR. The compound 1 showed moderate inhibiting activity against beta-glucuronidase enzyme

In the course of searching hepatoprotective agents from natural sources, the protective effect of chemical constituents of the marine brown alga Spatoglossum variabile Figaro et DE Notar (Dictyoaceae) against CCl₄-induced liver damage in Wistar rats was investigated. The compounds were first investigated for in vitro radical scavenging potential and were also tested for β-glucuronidase inhibition to further explore the relationship between hepatoprotection and antiradical potential.The compounds cinnamic acid esters 1 and 2 and aurone derivatives 3 and 4 were first investigated for in vitro radical scavenging potential against 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH), and superoxide anion radicals. In vivo hepatoprotective studies were performed in seven groups (n = 6) of Wistar rats. The test groups were pretreated with compounds (10 mg/kg body weight, po) orally for 30 min before the intraperitoneal administration of a dose of 20% CCl₄ diluted with dietary cooking oil. Moreover, compounds were also tested for β-glucuronidase inhibition to explore the relationship between hepatoprotection and radical scavenging potential.The test compounds 1-4 were found to exhibit antiradical activity against 1,1-diphenyl-2-picrylhydrazyl radicals with IC₅₀ values ranging between 54 and 138 µM, whereas aurone derivatives 3 and 4 additionally exhibited superoxide anion scavenging effects with IC₅₀ values of 95 and 87 µM, respectively. In addition, these compounds were found to be weak inhibitors of xanthine oxidase (IC₅₀ ≥1000 µM). In animal model, pretreatment with compounds 2-4 significantly blocked the CCl₄-induced increase in the levels of the serum biochemical markers.It appears that the hepatoprotection afforded by these compounds was mainly due to their radical scavenging activity that protected the cells from the free radicals generated by CCl₄-induced hepatotoxicity.

A novel beta-glucuronidase inhibiting triterpene (1) has been isolated from the chloroform fraction of Paeonia emodi beta-glucuronidase inhibit established ase chloroform fraction of Pa 11,beta,5alpha,23,24-pentahydroxy-30-norolean-12,20(29)-d ien-28-oic acid on the basis of spectroscopic analysis, including high resolution mass spectroscopy, one and two-dimensional NMR techniques. Oleanolic acid, betulinic acid, ethyl gallate, methyl grevillate and 1,5-dihydroxy-3-methylanthraquinone are also reported for the first time from Paeonia emodi.