Further terpenoids from Vitex negundo L. growing in Vietnam

Evaluation of the anti-inflammatory and antioxidant properties and isolation and characterization of a new bioactive compound, 3,4,9-trimethyl-7-propyldecanoic acid from Vitex negundo

ETHNOPHARMACOLOGICAL RELEVANCE

Herbal medicines derived from plant extraction are affordable, more therapeutically effective, and have fewer side effects than contemporary medications. Vitex negundo L. (V. negundo). is a medicinal shrub, which contains numerous phytoconstituents. In ancient medicinal practices, V. negundo was primarily prescribed as an analgesic and anti-inflammatory drug.

AIM OF THE STUDY

This study aims to evaluate the anti-inflammatory and antioxidant characteristics of crude extracts from V. negundo leaves, including those derived from petroleum ether (P), methanol (M), and aqueous (A) solvents. Additionally, the research seeks to identify the specific bioactive compounds responsible for these observed properties.

MATERIALS AND METHODS

The nitric oxide scavenging study was performed to evaluate the V. negundo crude extract's ability to function as a nitric oxide scavenger. Protein denaturation and proteinase inhibition experiments were employed to study the ability of extracts to suppress proteolysis and inhibit the enzymes that cause tissue injury. The membrane-stabilizing potency of plant extracts were examined through the process of heat-induced hemolysis. The ability of the extracts to neutralize free radicals showed a dose-dependent response, and the aqueous extract exhibited substantially higher activity in both FRAP and DPPH. The GC-MS analysis of V. negundo extracts revealed a vast array of pharmacologically active metabolites. Based on this Bioassay-guided fractionation approach, the optimal extract was selected for the potent molecule isolation and characterization.

RESULTS

The findings demonstrated that the aqueous extract of V. negundo exhibited markedly superior radical scavenging and anti-inflammatory capabilities compared to the other two extracts. Furthermore, a new molecule, 3,4,9-trimethyl-7-propyldecanoic acid was isolated from this extract, and its chemical structure was successfully determined.

CONCLUSION

This study revealed that the aqueous extract of V. negundo demonstrated notably stronger in vitro anti-inflammatory and antioxidant properties in comparison to the methanol and petroleum ether extracts. The identified active compound, 3,4,9-trimethyl-7-propyldecanoic acid is likely responsible for the extract's free radical scavenging and anti-inflammatory effects. Furthermore, conducting both in vitro and in vivo studies is crucial to substantiate the potential of this active constituent for the development of an anti-inflammatory drug derived from V. negundo.

New Halogenated Flavonoids from Adenosma bracteosum and Vitex negundo and Their α-Glucosidase Inhibition

Adenosma bracteosum and Vitex negundo are natural sources of methoxylated flavonoids. Little is known about the α-glucosidase inhibition of multi-methoxylated flavonoid derivatives. Eighteen natural flavonoids were isolated from A. bracteosum and V. negundo. Seven halogenated derivatives were synthesized. Their chemical structures were elucidated by extensive NMR analysis and high-resolution mass spectroscopy as well as comparisons in literature. All compounds were evaluated for their α-glucosidase inhibition. Most compounds showed good activity with IC50 values ranging from 16.7 to 421.8 μM. 6,8-Dibromocatechin was the most active compound with an IC50 value of 16.7 μM. A molecular docking study was conducted, indicating that those compounds are potent α-glucosidase inhibitors.

Traditional Medicinal Uses, Phytochemistry, Biological Properties, and Health Applications of Vitex sp

The genus Vitex is also known as a chaste tree, in which it is a large shrub native to the tropical and subtropical regions of the world. A diverse range of species is distributed throughout Southern Europe, the Mediterranean, and Central Asia. The Vitex tree, including its leaves and fruits, has been used for herbal remedies in the form of pastes, decoctions, and dried fruits since ancient times. This article aimed to prepare a comprehensive review of traditional uses and secondary metabolites derived from Vitex sp., including the chemical compounds, biological activities, application of Vitex in human clinical trials, toxicology and safety, marketed products, and patents. The scientific findings were obtained using a number of search engines and databases, including Google Scholar, PMC, and ScienceDirect. Vitex species are well known in pharmacology to have medicinal values, such as anti-inflammatory, antibacterial, antifungal, antimicrobial, antioxidant, and anticancer properties. Previous studies reported that some species are proven to be effective in treating diseases, such as diabetes, and improving female health. A total of 161 compounds from different Vitex species are reported, covering the literature from 1982 to 2022. A chemical analysis report of various studies identified that Vitex exhibited a wide range of phytoconstituents, such as iridoid, diterpenoid, ecdysteroid, and flavonoid and phenolic compounds. Apart from that, the review will also discuss the application of Vitex in human clinical trials, toxicology and safety, marketed products, and patents of the genus. While the extracts of the genus have been made into many commercial products, including supplements and essential oils, most of them are made to be used by women to improve menstrual conditions and relieve premenstrual syndrome. Among the species, Vitex agnus-castus L. is the only one that has been reported to undergo clinical trials, mainly related to the use of the genus for the treatment of mastalgia, menstrual bleeding problems, amenorrhea, menorrhagia, luteal insufficiency, and premenstrual syndrome. Overall, the review addresses recent therapeutic breakthroughs and identifies research gaps that should be explored for prospective research work.

Recurvataside, a new saponin from aerial parts of Mussaenda recurvata

A new glycoside, recurvataside (1) and six known compounds, quinovic acid (2), quinovic acid 28-O-β-D-glucopyranosyl ester (3), 3-O-β-D-glucopyranosylquinovic acid (4), 3-O-β-D-glucopyranosylquinovic acid 28-O-β-D-glucopyranosyl ester (5), pomolic acid (6), and ursolic acid (7) were isolated from aerial parts of Mussaenda recurvata. The structure of compound 1 was identified from its spectroscopic data and by comparison with the literature. Recurvataside represents the first occurrence of δ-oleanolic acid saponin bearing two D-glucose units at C-3 and C-28 in nature. This is the first time δ-oleanane-type saponin reported in the genus Mussaenda. Compounds 1-7 were evaluated the cytotoxicity against two cancer cell lines MCF-7 and HepG2. Among them, only compound 7 exhibited moderate activity against MCF-7 and HepG2 cell lines with IC₅₀ value of 16.97 ± 1.55 and 20.28 ± 1.00 μM, respectively. Compounds 1-7 were also tested for their inhibitory NO production in LPS-stimulated RAW264.7 cells. Compounds 3, 5, and 7 showed significant reduction of nitrite accumulation in LPS-stimulated RAW 264.7 cells with the IC₅₀ values of 8.81 ± 0.48, 13.42 ± 0.84, and 18.37 ± 0.67 μM, respectively.