Special metabolites isolated from Urochloa humidicola (Poaceae)

ABSTRACT This study aims to identify special metabolites in polar extracts from Urochloa humidicola (synonym Brachiaria humidicola) that have allelopathic effects and induce secondary photosensitization in ruminants. The compounds were isolated and identified via chromatographic and spectroscopic techniques. The compounds 4-hydroxy-3-methoxy-benzoic acid, trans-4-hydroxycinnamic acid, and p-hydroxy-benzoic acid; the flavonols isorhamnetin-3-O-β-d-glucopyranoside and methyl quercetin-3-O-β-d-glucuronate; and kaempferitrin, quercetin-3-O-α-l-rhamnopyranoside, and tricin were identified in the extract from the leaves of Urochloa humidicola. Two furostanic saponins, namely, dioscin and 3-O-α-l-rhamnopyranosyl-(1-4)-[α-l-rhamnopyranosyl-(1-2)]-β-d-glucopyranosyl-penogenin, as well as catechin-7-O-β-d-glucopyranoside were identified in the methanolic extract obtained from the roots of this plant. This species features a range of metabolites that may be toxic for animals if used in food and may interfere with the growth medium, thereby inhibiting the development of other species.

Characterization of natural organic matters effect on the biodegradation in the slow sand filter.

This study focuses on the differences in biodegradation of the natural organic matters (NOMs) of p-hydroxy-benzoic acid (PHBA) and 4-hydroxy-3-methoxy-benzoic acid (VA) with slow sand filter (SSF). The PHBA and VA were biologically transformed into another organic matter in the slow sand filtration (SSF) at the start-up period. The dissolved organic carbon (DOC) of PHBA and VA were stabilized at 2 mg/l after 5th day. The SUVA value of PHBA run decreased with higher sand depth and flow rate, and VA run's increased with higher sand depth, but smaller than PHBA run. Therefore, the PHBA promoted the DBPFP (formation potential of disinfection by products), the VA brought higher biodegradation and lower DBPFP.

Picrorhiza kurroa (Kutaki) Royle ex Benth as a hepatoprotective agent--experimental & clinical studies.

Picrorhiza kurroa (Pk), a known hepatoprotective plant, was studied in experimental and clinical situtations. The standardization of active principles--Picroside 1 and 2 was done with High Performance Liquid Chromatography. Picroside 1 ranged from 2.72 to 2.88 mg/capsule and picroside 2 from 5.50 to 6.00 mg/capsule. In the galactosamine-induced liver injury in rats, Pk at a dose of 200 mg/kg p.o. showed a significant reduction (p < 0.05) in liver lipid content, GOT and GPT. In a randomised, double-blind placebo controlled trial in patients diagnosed to have acute viral hepatitis (HBsAg negative), Pk root powder 375 mg three times a day was given for 2 weeks (n = 15) or a matching placebo (n = 18) was given. Difference in values of bilirubin, SGOT and SGPT was significant between placebo and Pk groups. The time in days required for total serum bilirubin to drop to average value of 2.5 mg% was 75.9 days in placebo as against 27.44 days in Pk group. The present study has shown a biological plausability of efficacy of Pk as supported by clinical trial in viral hepatitis, hepatoprotection in animal model and an approach for standardizing extracts based on picroside content.