Secondary metabolites from the stem of Ravenia spectabilis Lindl

Abstract

Background:Ravenia spectabilis is a medium tall shrub found widespread in South America. It also found in India, Pakistan, Bangladesh etc. Few alkaloid and steroid compounds were reported from the plant previously.Materials and Methods:Methanol extract from the stems of Ravenia spectabilis were partitioned into n-hexane, carbon tetrachloride, chloroform and aqueous soluble fractions, respectively. The crude methanol extract, carbon tetrachloride fraction and chloroform fraction were fractionated by column chromatography of Silica gel and Sephadex LH-20 for isolation and purification of compounds. The structures of the isolated compounds were determined by extensive NMR spectral analysis, including 2D NMR, mass spectroscopy etc.Results:Ten compounds, γ-fagarine (1), ravenoline (2), N-methyl atanine (3),2,3,3,5-tetramethyl-2,3,4,5- tetrahydrofurano [3,2-c] quinolin-4-one (4), arborinine (5), 3-geranyl indole (6), atanine (7), steroids sitosta-4-en- 3-one (8), stigmasterol (9) and 3-methoxy-4-hydroxy cinnamic acid (10) were isolated from the stems of Ravenia spectabilis.Conclusion:Compounds N-methyl atanine (3), 2,3,3,5-tetramethyl-2,3,4,5-tetrahydrofurano [3,2-c] quinolin-4-one (4), 3-geranyl indole (6), sitosta-4-en-3-one (8) and 3-methoxy-4-hydroxy cinnamic acid (10) were isolated from this plant for the first time. 3-geranyl indole (6) was also isolated second time from natural sources.

Evaluation of Alkaloids Isolated from Ruta graveolens as Photosynthesis Inhibitors

“…Accordingly, charge recombination is prevented by the presence of an electron-transport chain driving electrons towards P 700 ; a second light-harvesting process occurs at photosystem I (PSI), providing additional energy to electrons for their final purpose: production of adenosine triphosphate (ATP) and dihydronicotinamide-adenine dinucleotide phosphate (NADPH), which are used for CO 2 fixation through the Calvin cycle (biochemistry phase) [ 13 , 14 ]. Therefore, we analyzed chlorophyll a fluorescence kinetic transients to verify the damage on photosynthetic apparatus, demonstrating the quantitative and qualitative effects of herbicides on both photosystems [ 15 , 16 ]. From this perspective, the main goal of this report was to investigate the effects of alkaloids ( 1 – 8 ) isolated from Ruta graveolens L. ( Figure 1 ) on photosynthetic activities through polarography, chlorophyll (Chl) a fluorescence, and in vivo plant-growth experiments.…”