Journal of Asian Natural Products Research最新文献

To discover novel antimicrobial drug, 22 novel acylated derivatives were synthesized by A-ring modification of glaucocalyxin A. The structures of these derivatives were confirmed by NMR and MS data. In vitro antimicrobial activity of these compounds was evaluated against E. faecium, E. faecalis, MRSA, E. coli, A. baumannii and K. pneumoniae. The results showed compound 3d against E. faecium, E. faecalis and MRSA with a minimum inhibitory concentration of 4 μg/ml. And further molecular docking revealed that compound 3d has a higher binding affinity. In conclusion, compound 3d has the potential to develop into a new drug against drug-resistant bacteria.

Two new quinazolinone alkaloids, benzomalvin F (1), and quinadoline C (2), along with four known quinazolinones (3-6), were isolated from cultures of the wetland-soil-derived fungus Aspergillus udagawae from the Huixian wetland in Guilin. Their structures were elucidated based on detailed spectroscopic analysis, including 1D, 2D NMR, mass spectrometry, and IR spectra. In addition, the anti-inflammatory results showed that compounds 1, 2, 4, and 5 had significant inhibitory effects on NO production in RAW264.7 cells activated by lipopolysaccharide (LPS), with IC₅₀ values of 24.5 ± 0.1, 29.7 ± 0.1, 29.4 ± 0.1, and 31.0 ± 0.1 µM respectively, compared with the positive control indomethacin (IC₅₀ = 31.6 ± 0.4 μM).

The primary goal of this research was to isolate and assess the bioactive compounds within Eclipta prostrata Linn's chloroform extract, with a focus on their potential to combat arthritis, validating its traditional use. Initially, antioxidant characteristics were evaluated, followed by fractionation through column chromatography. The in-vivo safety assessment, following OECD TG 425 Guidelines, showed no mortality at doses up to 2000 mg/kg, confirming the fraction's safety. Subsequently, the active fraction was assessed in a complete Freund's adjuvant-induced arthritis model. It demonstrated a dose-dependent inhibitory effect on inflammation and improved various parameters, including thermal latency time, dorsal flexion, motility, and motor coordination. Active bio constituents like rutin, stigmasterol, quercetin, and beta-sitosterol were estimated in the active fraction. The findings provide validation for the traditional use of E. prostrata as a potential plant with anti-arthritic properties, suggesting its potential suitability for rheumatoid arthritis treatment.

Three new compounds, including two glycosides, named gerbelavinsides E/G (1/2), and a flavone, named gerbelavin G (3), were isolated from 50% ethanol extract of Gerbera delavayi. Their structures were elucidated based on HR-ESI-MS, IR, UV and NMR spectral data, and the absolute configurations of 1 and 3 were determined by ECD spectra. Three compounds were tested for their inhibition effect against LPS-induced NO production in RAW 264.7 cells. They exhibited different degrees of inhibition activities with rates of 40.55 ± 1.65%, 70.13 ± 0.55%, 56.74 ± 1.15%, respectively.

By establishing an in vitro model of D-Gal-induced brain neuronal cell (HT-22) senescence, it was found that TAX treatment significantly increased the activities of SOD and GSH, while decreasing MDA levels in aging HT-22 cells, indicating that TAX effectively restored the total antioxidant capacity and antioxidant enzyme activity of aging HT-22 cells induced by D-Gal, and attenuated cellular oxidative stress injury. In addition, taxifolin could also protect HT-22 cells from aging by up-regulating SIRT1 while reducing the expression of Ac-p53, indicating that TAX may be an active substance that can effectively delay cell aging.

Respiratory syncytial virus (RSV) is a widespread viral infection that causes millions of high-risk illnesses annually. Medicinal herbs such as ginseng root, echinacea purpurea, and radix astragali have a positive effect on antiviral activity by preventing viral adhesion, syncytial development, inhibiting viral internalization, relieving respiratory inflammation, strengthening the immune system, and stimulating the release of interferons. The potential benefits of natural products in terms of lower costs, better patient outcomes, and fewer adverse effects are discussed. This review examines the current evidence on the prevention and control of RSV with natural ingredients and the challenges and opportunities in clinical practice.

The global aging population highlights the need for effective anti-aging treatments. Natural products show promise, but thorough evaluation requires in vivo models due to the complexity of aging. Ethical concerns are driving a shift from traditional models like rabbits and mice to alternatives such as Caenorhabditis elegans. This microscopic nematode, with its short life cycle, genetic similarities to humans, and cost-effectiveness, is ideal for testing anti-aging compounds. We review studies using C. elegans to assess natural products, suggesting it could serve as a primary model for -evaluating the safety and efficacy of plant-derived anti-aging compounds.

Epimedium is widely used in traditional Chinese medicine and contains rich bioactive compounds. These compounds often have a methyl group at their 4'-OH position catalyzed by methyltransferases. Therefore, studying methyltransferases in Epimedium plants is of great significance. In this study, a flavonol methyltransferase, EpOMT4, was isolated from Epimedium pseudowushanense B.L. Guo. The recombinant enzyme regiospecifically transferred a methyl group to the 4'-OH position of 8-prenylkaempferol forming icaritin. The study demonstrates that enzymatic methylation of flavonoids in Epimedium plants holds significant potential and could provide a promising alternative method for the biosynthetic production of bioactive methylated prenylflavonoids.

The incidence of Alzheimer's is increasing and poses a significant social and economic burden. The pathogenesis involved in the expansion of AD includes neuronal oxidative damage, tau phosphorylation, amyloid beta aggregation, neuroinflammation, etc. Despite enormous efforts, there is currently no effective treatment or cure for this condition in the allopathic system. Marine compounds are appealing options and have a strong neuroprotective impact. Marine-derived compounds from sponges, algae, and marine invertebrates can be used for neuroprotection, with fewer adverse effects than synthetic drugs. Various compounds such as bryostatin-1, docosahexaenoic acid, spirolides, and astaxanthin, GV-971, have demonstrated outstanding activity and bioavailability.