ß-sitosterol isolated from the leaves of Trema orientalis (Cannabaceae) promotes viability and proliferation of BF-2 cells.

Trema orientalis is a pioneer species in the cannabis family (Cannabaceae) that is widely distributed in Thai community forests and forest edges. The mature leaves are predominantly used as an anti-parasite treatment and feed for local freshwater fish, inspiring investigation of their phytochemical composition and bioactivity. The purpose of this work was to investigate the bioactive compounds in T. orientalis leaf extract and their cytotoxicity in the BF-2 fish cell line (ATCC CCL-91). Flash column chromatography was used to produce 25 mL fractions with a mixture solvent system comprised of hexane, diethyl ether, methanol, and acetone. All fractions were profiled with HPLC-DAD (mobile phase methanol:aqueous buffer, 60:40 v/v) and UV detection (wavelengths 256 and 365 nm). After drying, a yellowish powder was isolated from lipophilic leaf extract with a yield of 280 µg/g dry weight. Structure elucidation by nuclear magnetic resonance (NMR) indicated it to consist of pure ß-sitosterol. The lipophilic extract and pure compound were evaluated for cytotoxicity using BF-2 cells. MTT assays showed both leaf extract and pure compound at 1 µg/mL to increase cell viability after 24 h treatment. The respective half maximal inhibitory concentration (IC50) values of leaf extract and ß-sitosterol were 7,027.13 and 86.42 µg/ml, indicating a lack of toxicity in the BF-2 cell line. Hence, T. orientalis can serve as a source of non-toxic natural lipophilic compounds that can be useful as bioactive ingredients in supplement feed development.

Computational Analysis and Biological Activities of Oxyresveratrol Analogues, the Putative Cyclooxygenase-2 Inhibitors.

Polyphenols are a large family of naturally occurring phytochemicals. Herein, oxyresveratrol was isolated from ethanolic crude extracts of Artocarpus lacucha Buch.-Ham., and chemically modified to derive its lipophilic analogues. Biological screening assays showed their inhibitory potency against cyclooxygenase-2 (COX-2) with very low cytotoxicity to the MRC-5 normal cell lines. At the catalytic site of COX-2, docking protocols with ChemPLP, GoldScore and AutoDock scoring functions were carried out to reveal hydrogen bonding interactions with key polar contacts and hydrophobic pi-interactions. For more accurate binding energetics, COX-2/ligand complexes at the binding region were computed in vacuo and implicit aqueous solvation using M06-2X density functional with 6-31G+(d,p) basis set. Our computational results confirmed that dihydrooxyresveratrol (4) is the putative inhibitor of human COX-2 with the highest inhibitory activity (IC50 of 11.50 ± 1.54 µM) among studied non-fluorinated analogues for further lead optimization. Selective substitution of fluorine provides a stronger binding affinity; however, lowering the cytotoxicity of a fluorinated analogue to a normal cell is challenging. The consensus among biological activities, ChemPLP docking score and the binding energies computed at the quantum mechanical level is obviously helpful for identification of oxyresveratrol analogues as a putative anti-inflammatory agent.

Yanangdaengin, a dihydrochalcone glucoside galloyl ester as active antioxidative agent from leaves of Lysiphyllum strychnifolium (syn. Bauhinia strychnifolia).

Objective: To isolate and identify the major bioactive components from the leaves of Lysiphyllum strychnifolium, an indigenous herb used in traditional Thai medicine for detoxification, longevity, and some other health related issues. Methods: Comparative HPLC analyses of the crude extracts from three provenances were carried out for an overview of characteristic compound profiles. Isolation of the major compounds was undertaken with chromatographic methods. Chemical structures were elucidated by NMR spectroscopic techniques and mass spectrometry. DPPH scavenging assay was carried out to determine the free radical scavenging activity of isolated compounds. Results: Yanangdaengin (3), a dihydrochalcone glucoside galloyl ester, has been isolated together with its corresponding dihydrochalcone glucoside trilobatin (2) as major compounds from the leaves of L. strychnifolium. Additionally, gallic acid (1) was co-chromatographically identified. Free radical scavenging activity of isolated compounds were determined. Compound 3 exhibited higher free radical scavenging activities in comparison to Trolox and quercetin. Conclusion: The isolated compounds could be used as chemical markers for quality assessment. The present work could promote the quality control and herbal medicinal product development of this plant.

Simultaneous HPLC analysis of crebanine, dicentrine, stephanine and tetrahydropalmatine in Stephania venosa

ABSTRACT Stephania venosa (Blume) Spreng., Menispermaceae, has been traditionally used as tonic drug and treatment of various diseases in South East Asian countries. In order to evaluate the quality and standardization of S. venosa roots, the HPLC method for quantification of the content of major components in S. venosa was developed and validated. The chromatographic separation was performed on a Hypersil BDS C18 column using gradient system of 100 mM ammonium acetate in water and methanol with flow rate 1 ml/min. Detection wavelength was set at 210 nm for tetrahydropalmatine, 280 nm for dicentrine and crebanine, and 270 nm for stephanine. The validated method showed good sensitivity, linearity, precision, and accuracy. The suitable solvent that yielded highest alkaloids contents from the matrix was optimized. S. venosa samples collected from various locations were analyzed. The present study provided comprehensive overview of major components in S. venosa. A remarkable variation in the accumulation of alkaloids in each population and the between individual in the same population could be observed. Our results showed the heterogeneity of S. venosa in Thailand which would need a further study for species delimitations.