Analysis of Biochemical and Antimicrobial Properties of Bioactive Molecules of Argemone mexicana.

This study identified phytochemicals in Argemone mexicana (A. mexicana) extracts that are responsible for its medicinal properties, and the best solvent for their extraction. The extracts of the stem, leaves, flowers, and fruits of A. mexicana were prepared at low (corresponding to room temperature) and high temperatures (corresponding to the boiling points) in various solvents, viz., hexane, ethyl acetate, methanol, and H2O. The UV-visible absorption spectra of various phytoconstituents in the isolated extracts were determined through spectrophotometry. Qualitative tests for the screening of phytoconstituents in the extracts were performed to identify various phytochemicals. We identified the presence of terpenoids, alkaloids, cardiac glycosides, and carbohydrates in the plant extracts. The antioxidant and anti-human immunodeficiency virus type 1 reverse transcriptase (anti-HIV-1RT) potential, as well as the antibacterial activity of various A. mexicana extracts were determined. These extracts showed strong antioxidant activities. The extracts exhibited antimicrobial activities against Salmonella typhi, Staphylococcus epidermis, Citrobacter, Neisseria gonorrhoeae, and Shigella flexineri. These extracts significantly inhibited HIV-1 reverse transcriptase activity. The aqueous leaf extract prepared at a temperature equivalent to the boiling point, i.e., 100 °C, was identified to be the most active against pathogenic bacteria and HIV-1 RT.

Chemical characterization, antioxidant and anti-HIV activities of a Brazilian propolis from Ceará state

ABSTRACT Propolis (bee glue) a product of Apis mellifera L. is a resinous mixture containing chiefly beeswax and resin harvested by bees from plant leaves, buds and exudates. Extracts of a propolis sample from Salitre, a municipality of Ceará state (northeast Brazil) were obtained with solvents of increasing polarity (hexane, chloroform, ethyl acetate and methanol). A chemical profile was carried out by GC-EI-MS and HPLC-DAD-ESI-MS/MS. Lupenone, lupeol, octanoic acid tetracosyl ester and octanoic acid hexacosyl ester were identified by GC-EI-MS. Antioxidant activity was evaluated by the DPPH and β-carotene discoloring methods, and anti-HIV activity by the in vitro inhibition of HIV-1 reverse transcriptase. The ethyl acetate extract exhibited the highest antioxidant and anti-HIV activity and was fractioned by column chromatography using silica gel and seven different eluents. The active fractions were submitted to semi preparative HPLC and the following compounds were isolated: caffeic acid, p-coumaric acid, diprenylcinnamic acid, quercetin, naringenin, isorhamnetin, quercetin-3-O-diglucoside,4,2′,4′-trihydroxy-2-methoxychalcone, gossypetin-3,3′,4′,7-tetramethyl ether, myricetin-3,7,3′-trimethyl ether and 5-hydroxy-3,6,7,8,4′-pentamethoxyflavone. The ethyl acetate extract and its fractions F5-F7, as well as quercetin, isorhamnetin, myricetin-3,7,3′-trimethyl ether and p-coumaric acid exhibited high antioxidant activity on both DPPH and β-carotene antioxidant methods. Isorhamnetin exhibited moderate inhibitory effect against HIV-1 reverse transcriptase (56.99 ± 3.91%), followed by naringenin (44.22 ± 1.71%), quercetin (43.41 ± 4.56%) and diprenylcinnamic acid (41.59 ± 2.59%). These results agree with previous authors who reported anti-HIV activity of flavonoids.