Leptocarposide: a new triterpenoid glycoside from Ludwigia leptocarpa (Onagraceae)

Triterpene and Steroids from Ludwigia abyssinica A. Rich (Onagraceae) Displayed Antimicrobial Activities and Synergistic Effects with Conventional Antibiotics

Difficulties encountered in treating drug-resistant pathogens have created a need for new therapies. Synergistic combinations of antibiotics are considered as ideal strategies in combating clinical and multidrug-resistant (MDR) infections. In this study, the antimicrobial activities of triterpenes and steroids from Ludwigia abyssinica A. Rich (Onagraceae) and their combined effects with antibiotics were assessed. The associations between plant constituents and antibiotics were evaluated by determining their fractional inhibitory concentrations (FICs). Sitost-5-en-3β-ol formiate (1), 5α,6β-dihydroxysitosterol (2), and maslinic acid (3) were isolated from the L. abyssinica ethyl acetate (EtOAc) extract. The EtOAc extract, compounds 1, 2, and 3 (MIC = 16-128 µg/mL) would be the best antibacterial and antifungal agents. The antimicrobial activities of amoxicillin were relatively weak against MDR Escherichia coli and Shigella flexneri and significant against Staphylococcus aureus ATCC 25923. However, when used in association with plant constituents, it displayed an interesting synergistic effect. Among plant components-antibiotic combinations, the EtOAc extract and compound 1 (steroid) showed a synergistic effect with amoxicillin/fluconazole against all the tested microorganisms whereas the association of compound 3 (triterpenoid) and amoxicillin/fluconazole displayed an additive effect against Shigella flexneri and Escherichia coli and a synergistic effect on Staphylococcus aureus, Cryptococcus neoformans, Candida tropicalis, and Candida albicans ATCC 10231. Overall, the results of the present study demonstrated antibacterial and antifungal activities of extracts and compounds isolated from L. abyssinica. The findings of the current study also showed that the potency of antibiotics was improved when screened in combination with L. abyssinica components, supporting the drug combination strategy to combat antimicrobial resistance.

The potential and outgoing trends in traditional, phytochemical, economical, and ethnopharmacological importance of family Onagraceae: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

The Onagraceae is a widely distributed family of flowering plants comprises about 17 genera and more than 650 species of herbs, shrubs, and trees. Onagraceae also common as willowherb family or evening primrose family is divided into two subfamilies; Ludwigioideae (mainly genus; Ludwigia) and Onagroideae. Family Onagraceae is characterized by its numerous traditional uses as treatment of hormonal imbalances, urinary system ailments, prostate health maintenance, and antimicrobial effects.

AIM OF THE STUDY

This review aims to introduce a holistic overview on the phytochemical composition, economical importance and ethnopharmacological value of different species of family Onagraceae.

MATERIALS AND METHODS

Literature review was performed using different data bases such as PubMed, Web of Science, Google Scholar and Reaxys searching for articles focused on phytochemical composition, bioactivity and ethnopharmacological history of Onagraceae species.

RESULTS

Different species of Onagraceae were reported to have a great variety of phytochemicals including flavonoids, tannins, phenolic acids, triterpenoids, saponins, and volatile/fixed oils. Onagraceae exhibited several health benefits and pharmacological activities including anti-inflammatory, antiarthritic and analgesic, antioxidant, cytotoxic, antidiabetic, and antimicrobial.

CONCLUSIONS

Family Onagraceae is an extremely important family with diverse phytochemical composition which enriches their pharmacological importance and hence it's commercial and economical value.

Triterpenoids

Covering 2014. Previous review: Nat. Prod. Rep., 2017, 34, 90-122 This review covers the isolation and structure determination of triterpenoids reported during 2014 including squalene derivatives, lanostanes, holostanes, cycloartanes, cucurbitanes, dammaranes, euphanes, tirucallanes, tetranortriterpenoids, quassinoids, lupanes, oleananes, friedelanes, ursanes, hopanes, serratanes, isomalabaricanes and saponins; 374 references are cited.