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"The metabolites from microorganisms for rapidly grawing field,due to the suspicion that a number of metabolites obtained from reef's invertebrates are produced by associated microorganisms....."

"Several series of trawl surveys were carried out in the waters of Perhentian Islands using commercial trawlers.16S mithochondrial rRNA gene sequences were used to infer the phylogenetic relationship among nine morphospecies of leiognathids...."

"buku ini membahas tetang virus molekuler secara spesifik"

"Penelitian ini dilakukan untuk mencari beberapa senyawa kimia dari ekstrak kulit pohon Garcinia tetrandra serta uji aktivitas biologi terhadap Artemia salina L. dan aktivitas antibakteri. Senyawa tersebut diisolasi dengan cara ektraksi dalam n-heksan selanjutnya ekstraksi dengan aseton . Masing-masing ekstrak dipisahkan dengan cara kromatografi kolom dengan fasa diam silika gel dan fasa geraknya adalah n-heksan , etil asetat, metanol secara gradien. Senyawa kimia yang telah murni ditentukan struktur molekulnya dengan cara spektrofotometri UV-Vis, spektrofotometri Infra Merah, Spektrometri Massa, Spektrometri Resonansi Magnet inti 3H dan 13 C. Dari hasil penelitian ini diperoleh senyawa GT-1 yang mempunyai rumus molekul C23HxoO6 , diperkirakan sama dengan Thwaitesixanton, senyawa GT-2 dengan rumus molekul C30H500 yang diperkirakan senyawa 3-a- (22) (29) Hopen-ol; Senyawa GT-3 dengan rumus molekul C38H50O6 yang diperkirakan sama dengan Camboginol; Senyawa GT-4 dengan rumus molekul C38H5006 yang diperkirakan sama dengan cambogin. Dari senyawa - senyawa tersebut yang memiliki aktivitas antimikroba adalah senyawa GT-3 dengan diameter harnbatan rata-rata = 8 mm/1000 ppm.terhadap bakteri B. subtilis ATCC 6633, E. coli ATCC 25922, S. aureus ATCC 6538, M. phlei DSM 43286. Dari hasil uji aktivitas terhadap larva-udang Artemia salina Leach., senyawa yang memiliki aktivitas yang cukup signifikan adalah senyawa GT-3 dan GT-4 dengan LC50 masing-masing 7µg/ ml dan 18µg/ ml.

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Isolation, Structure Elucidation, Biological Activity Test of Chemical Constituents of Stem Bark of Garcinia Tetrandra PierreThis study was caned out to obtain several chemical constituents of the extract of the stem bark of Garcinia tetrandra Pierre, their biologic are activity to Artemia salina Leach and their antibacterial activity. The compounds were isolated from the n-hexane and acetone - soluble extracts. Each extract was separated through a column chromatography on silica gel G , as the stationary phase which gradient mixtures, of n-hexane, ethyl-acetate and methanol as the mobile phase. The purified chemical constituents were identified their structures based on their UV -- Visible , Infra Red Spectrophotometry , Mass Spectrometry, 1H and '3C - Nuclear Magnetic Resonance Spectrometry data. The first isolate of GT-I with its molecular formula of C23HxoO6 was identified as Thawaitesixantone; GT-2 with and its molecular ion formula of C30H50O was identified as 3-a-(22)(29) Hopen-ol; GT-3 with its molecular formula of C38H50O6 was identified as camboginol; GT- 4 with its molecular formula of C38H5006 was identified as cambogin. From of all of the isolated compounds GT-3, showed antibacterial activity. In a concentration of 1000 ppm, its inhibition against the growth off B. subtilis ATCC 6633, E. code ATCC 25922, S. aureus ATCC 6538, M phlei DSM 43286 were 8 mm. From the results of toxicity evaluation to the Artemia salina Leach , GT-3 and GT-4 with its LC50 7µg/ ml and 18 µg/ ml, respectively."