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Isolasi dan Uji Aktivitas Senyawa Bioaktif Antibakteri dari Aktinomisetes TN 15-7.
No full textAktinomisetes merupakan mikroba yang paling banyak memproduksi senyawa
bioaktif dibandingkan mikroorganisme lain. Beberapa diantaranya merupakan antibiotik
terkenal seperti streptomisin. Kelimpahan aktinomisetes di alam sangat luas dengan
keragaman kondisi lingkungan. Penelitian ini bertujuan mengisolasi senyawa bioaktif
aktinomisetes TN 15-7 yang diisolasi dari tanah rhizosfer tumbuhan Angelonia sp koleksi
PUSLIT Biologi LIPI dan uji aktivitas antibakteri terhadap S. aureus Ina-CC B4 dan E.
coli Ina-CC B5 secara kualitatif melalui uji KLT-bioautografi dan kuantitatif melalui
penentuan nilai konsentrasi hambat minimum (KHM). Kloramfenikol digunakan sebagai
standar antibakteri. Dua senyawa bioaktif berhasil diisolasi dan menunjukan aktivitasnya
sebagai antibakteri melalui KLT-bioautografi terhadap S.aureus (fraksi F3.4/F3.5/F3.6 dan
F6.6) dan E.coli (fraksi F6.6). Fraksi F3.4/F3.5/F3.6 memiliki aktivitas antibakteri yang
kuat dengan nilai KHM 32 μg/mL terhadap bakteri S.aureus dan fraksi F6.6 memiliki
aktivitas antibakteri yang sedang dengan nilai KHM 256 μg/mL terhadap bakteri S.aureus
dan E.coli. Kapasitas produksi fraksi F3.4/F3.5/F3.6 sebesar 8.1 mg/L dan fraksi F6.6
sebesar 3.3 mg/L
Isolasi dan Uji Antimikrob Metabolit Sekunder Ekstrak Kultur Jamur Endofit AFKR-5 dari Tumbuhan Akar Kuning (Arcangelisia flava (L) Merr)
No full textEndophytic fungi associated with medicinal plant were known to produce bioactive secondary metabolites similar to its host plant. This study aimed to obtain bioactive secondary metabolites as antimicrobial from endophytic fungi AFKR-5 associated with akar kuning plant from Bogor Botanical Garden. Methanol fraction of ethyl acetate extract from AFKR-5 culture in potato dextrose broth medium was capable to produce the bioactive secondary metabolites F3.4 (10.375 mg/L) with retention factor of 0.30. Antimicrobial activity test using Kirby-Bauer disc diffusion method showed that F3.4 was a broad antimicrobial spectrum on 3 pathogenic microbes, namely Gram-positive bacteria Staphylococcus aureus, Gram-negative bacteria Escherichia coli, and Candida albicans mold. The determination of minimum inhibitory concentration (MIC) and the minimum fungicidal concentration (MFC) were carried out with liquid microdilution method. F3.4 was the most potential with MIC value of 16 μg/mL against C. albicans, twice as stronger than the commercial antifungal Nystatin which was only fungistatic with MIC value of 32 μg/mL. F3.4 was fungicidal with MFC value of 32 μg/mL against C. albicans, so that it is potential to be developed as antimicrobial, especially antifungal
Fraksi Antioksidan dan Antibakteri dari Jamur Endofit G1BP-10 yang Berasosiasi dengan Tanaman Manggis (Garcinia mangostana).
No full textJamur endofit adalah mikroorganisme yang hidup di dalam sistem jaringan
tumbuhan, yang terbukti mengandung senyawa bioaktif dengan beragam struktur.
Salah satu jamur endofit yang berhasil diisolasi dari tanaman manggis, yaitu
G1BP-10, diketahui memiliki aktivitas antioksidan dan antibakteri terhadap
Staphylococcus aureus dan Escherichia coli. Isolat jamur dikultur dalam media
potato dextrose broth dan ekstrak etil asetat kultur tersebut difraksionasi untuk
mendapatkan fraksi yang terindikasi mengandung senyawa aktif. Noda aktif
ekstrak etil asetat jamur dideteksi melalui uji bioasai dengan metode bioautografi
langsung. Ekstrak mampu menghambat pertumbuhan bakteri S. aureus dan E.
coli dengan nilai konsentrasi hambat minimum (KHM) masing-masing 32 μg/mL
dan 64 μg/mL. Ekstrak juga aktif sebagai antioksidan berdasarkan metode uji
menggunakan 2,2-difenil-1-pikrilhidrazil dengan konsentrasi hambat 50% (IC50)
10.52 μg/mL dan nilai antioxidant activity index (AAI) 2.93. Fraksionasi
menghasilkan F9J1 yakni fraksi teraktif antioksidan kuat dengan nilai AAI 1.32,
selain itu F9J3 merupakan fraksi antibakteri kuat terhadap bakteri S. aureus
dengan nilai KHM 32 μg/mL, tetapi lemah terhadap E. coli dengan nilai KHM >
256 μg/mL
Biotransformation of (-)-Epigallocatechin-3-O-gallate into (-)-2R,3S-Dihydromyricetin by the Endophytic Fungus Diaporthe sp. E Isolate Obtained from a Tea Plant
Full text linkEndophytic fungi have been reported possess an interesting ability to mimic their host plant metabolites. Several fungi also show their specific capability to biotransform the chemical constituents of the host plant. The endophytic fungus Diaporthe sp. E isolate obtained from young stem of a tea plant (Camellia sinensis) show their unique capability to biotransform (-)-epigallocatechin-3-O-gallate [(-)-EGCG] into a major product in glucose-peptone-yeast extract medium that incubated under dark condition at 27 oC for 48 h. The major biotransformation product were isolated and purified through column chromatography techniques using Sephadex LH-20 and silica gel. The chemical structure of the major product were elucidated as (-)-2R,3S-dihydromyricetin based on their IR, FAB-MS, 1D- and 2D-NMR spectra. Key words: (-)-2R,3S-dihydromyricetin, (-)-EGCG, (-)-2R,3R,4R-leucodelphynidin, biotransformation, Diaporthe sp. E isolate, endophytic fungus, Camellia sinensi
HAYATI Journal of Biosciences Vol. 14 No. 4 Tahun 2007
No full textEndophytic fungi have been reported possess an interesting ability to mimic their host plant metabolites. Several fungi also show their specific capability to biotransform the chemical constituents of the host plant. The endophytic fungus Diaporthe sp. E isolate obtained from young stem of a tea plant (Camellia sinensis) show their unique capability to biotransform (-)-epigallocatechin-3-O-gallate [(-)-EGCG] into a major product in glucose-peptone-yeast extract medium that incubated under dark condition at 27 oC for 48 h. The major biotransformation product were isolated and purified through column chromatography techniques using Sephadex LH-20 and silica gel. The chemical structure of the major product were elucidated as (-)-2R,3S-dihydromyricetin based on their IR, FAB-MS, 1D- and 2D-NMR spectra
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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