Steroidal constituents of rice (Rryza sativa) hulls with algicidal and herbicidal activity against blue-green algae and duckweed.
Two new compounds, 14-methyl stigmast-9(11)-en-3alpha-ol-3beta-D-glucopyranoside (1) and cholest-11-en-3beta, 6beta, 7alpha, 22beta-tetraol-24-one-3beta-palmitoleate (2), along with the known compound beta-sitosteryl-3beta-D-glucopyranosyl-6'-linoleiate (3), were isolated from the methanolic extract of rice (Oryza sativa) hulls. The structures of the two new compounds were elucidated using one- and two-dimensional NMR in combination with IR, EI/MS, FAB/MS, HR-EI/MS and HR-FAB/MS. In bioassays with blue-green algae, Microcystis aeruginosa UTEX 2388 and duckweed, Lemna paucicostata Hegelm 381, the efficacy of bioactivity of the two new compounds linearly increased as the concentration increased from 0.3 to 300 IgM. Compared with momilactone A, compounds 1 and 2 showed similar and higher inhibitory activities against the growth of M. aeruginosa at a concentration of 300 microM. However, compound 2 was similar to momilactone A in inhibiting L. paucicostata growth at a concentration of 300 microM. As a result, compound 2 appears to have a strong potential for the environmentally friendly control of weed and algae that are harmful to water-logged rice.
Chung
Ill-Min
IM
Department of Applied Life Science, Konkuk University, Seoul 143-701, South Korea.
Ali
Mohd
M
Ahmad
Ateeque
A
Chun
Se-Chul
SC
Kim
Jung-tae
JT
Sultana
Shahnaz
S
Kim
Jin-Seog
JS
Min
Suk-Ki
SK
Seo
Bo-Ram
BR
D002775:Cholestadienols / Q000737:chemistry* / Q000633:toxicity*; D000458:Cyanobacteria / Q000502:physiology*; D004224:Diterpenes / Q000633:toxicity; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry* / Q000633:toxicity*; D005960:Glucosides / Q000737:chemistry* / Q000633:toxicity*; D006540:Herbicides; D006868:Hydrolysis; D007783:Lactones / Q000633:toxicity; D008041:Linoleic Acids / Q000737:chemistry* / Q000633:toxicity*; D009682:Magnetic Resonance Spectroscopy; D046931:Microcystis / Q000187:drug effects; D012275:Oryza / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000633:toxicity; D012855:Sitosterols / Q000737:chemistry* / Q000633:toxicity*; D021241:Spectrometry, Mass, Electrospray Ionization; D016339:Spectrometry, Mass, Fast Atom Bombardment; D013055:Spectrophotometry, Infrared; D013256:Steroids / Q000737:chemistry* / Q000633:toxicity*
C519674:14-methyl stigmast-9(11)-en-3alpha-ol-3beta-D-glucopyranoside; D002775:Cholestadienols; D004224:Diterpenes; D005229:Fatty Acids, Monounsaturated; D005960:Glucosides; D006540:Herbicides; D007783:Lactones; D008041:Linoleic Acids; D010936:Plant Extracts; D012855:Sitosterols; D013256:Steroids; C519675:beta-sitosteryl-3beta-D-glucopyranosyl-6'-linoleiate; C519673:cholest-11-en-3beta, 6beta, 7alpha, 22beta-tetraol-24-one-3beta-palmitoleate; C477203:momilactone B; C116023:momilactone A