Investigation Of Alisma Orientale And Scrophularia Ningpoensis On Chemical Constituents And Bioactivities

Terpenoids is one of the substances in Natural Pharmaceutical Chemistry,its molecular skeleton is composed by isoprene or isopentane unit as the basic structural unit,linked in a variety of ways.There are many structure types including monoterpenes,sesquiterpenoids,iridoids,diterpenoids and triterpenoids.This constituent is widely found in plants;it is an important secondary metabolite and has many biological activities.Alisma orientale(Sam.)Juzep and Scrophularia ningpoensis Hemsl.were traditional therapeutic drugs in China.Both of these herbs are rich in terpenes and have anti-inflammatory effect including sesquiterpene,triterpenoids,iridoids and glycosides.In order to elucidate the bioactive constituents of these two traditional Chinese medicine,and explore new type biological activity lead compounds,their secondary metabolites were investigated systematically and the structures of these compounds were determined based on detailed spectroscopic data analyses.The cytotoxic,antimicrobial,anti-inflammatory and α-glucosidase inhibitory activities of the isolated compounds were evaluated.61 compounds including nineteen triterpenoids(1-19),ten sesquiterpenoids(20-29),two alkaloids(30-31),10 iridoid glycosides compounds(36,37,38,39,40,44,45,46,53 and 54),five phenylpropanoids(48-52),three 2-pyrrolidones(41-43)and other compounds(32-35,47,55-61)were isolated from Alisma orientale and Scrophularia ningpoensis by various chromatographic separation methods and spectrum technology.Among them,twelve compounds(1,2,4,20,29,36,37,38,39,40,41 and 42)were determined as new compounds,55 was a new natural product.Five compounds(22,23,27,30 and 31)were isolated from Alisma orientale for the first time and five compounds(50,51,52,58 and 59)were isolated from Scrophularia ningpoensis for the first time.The cytotoxic,antibacterial,antifungal,anti-inflammatory,and α-glucosidase inhibitory activities of isolated compounds were evaluated.The human large-cell lung cancer cell line H460,human breast cancer cell line MCF-7,and human prostate cancer cell line PC-3 were used to evaluate the cytotoxic effects of all these isolates using the MTT method,nine compounds(6,8-12,17,20 and 27)exhibited cytotoxicities with IC50 values ranging from 11.5 ±1.7 μM to 76.7 ± 1.4 μM.We used a micro broth dilution assay to evaluate the minimum inhibitory concentrations(MICs)of terpenoids against Bacillus subtilis ATCC 6633,Staphylococcus aureus ATCC 25923,Escherichia coli ATCC 25922,Candida albicans ATCC MYA-2876,and Candida parapsilosis ATCC 22019.Eight compounds(6,9-12,16,22 and 27)showed antibacterial activities against the Gram-positive strains Bacillus subtilis and Staphylococcus aureus with MIC values of 12.5-100 mg/mL.The nitrite concentration in the medium was measured using the Griess reaction to indicate NO production with IC50 values ranging from 3.8 ± 1.8μM to 91.34±5.9 μM(1,14,16,29,41/42,47 and 59).The α-glucosidase inhibitory activity of compounds were tested and p-nitrophenyl-α-D-glucopyranoside(PNPG)was used as a substrate.Further,the initial cytotoxic and antibacterial SAR of 3-oxo-protostanes were deduced.These findings will provide valuable information for the application of the traditional medicine A.orientale and S.ningpoensis...