Keragaman Bakteri Endofit Penghasil L-Asparaginase Bebas L-Glutaminase

Endophytes are potential as a source of active compound producer. Endophytes that is isolated from tropical medicinal plants has been getting attention due to its high biodiversity and active compound producing ability. L-asparaginase is the first enzyme used as chemotherapeutic agent for leukemia. The aim of this study is to collect the endophytic bacteria associated with tropical medicinal plants from Sumba Island and investigate the activity of L-asparaginase without L-glutaminase from endophytic bacteria isolates. The samples Gliricidia sepium, Pittosporum moluccanum, Clerodendrum buchanani, and Zingiberaceae are collected from Wanggameti, East Sumba, NTT. Samples are sterilized using surface-sterilization method and endophytic bacteria are isolated using plant piece method on R2A media. Selected endophytic bacteria are identified by 16S rDNA sequences. L-asparaginase screening is conducted using modified R2A with addition of L-asparagine and phenol red as colour indicator. A total of 34 isolates of endophytic bacteria were collected from 5 samples. A total of 14 genus consisted of 17 different bacterial species were obtained from 34 selected isolates. Endophytic bacteria of P. stutzeri strains of SMKL1 and R. radiobacter strains of SMKW2 from the Kahili plant were needed as L-glutaminase-free L-asparaginase and were potential to be candidate of leukemia cancer chemotherap

Isolation and Screening for IAA production, Nitrogen Fixation, P-Solubilization and Cellulolytic Activity of Plant Growth-Promoting Rhizobacteria from Imperata cylindrica Grasslands

Indigenous Plant Growth-Promoting Rhizobacteria (PGPR) are naturally occur for enhancement of soil fertility, producing plant growth hormones, nitrogen fixing, bio-composting and biodegradation of organic substances of soil without damaging the ecosystem. The objectives of this study was to isolate beneficial microbes using direct and enrichment methods on specific media, and screen these isolates for PGPR traits of Rhizobium-like strains, Azotobacter-like strains, Azospirillum-like strains and phosphate solubilizer-like strains isolated from four Imperata grasslands in Indonesia. About 208 isolates were isolated using direct and enrichment method from Cibinong (CSC); Central Kalimantan (Katingan) and Nusa Tenggara Timur (SV and RM) on specific media screened for IAA, phosphate solubilization, nitrogen fixation and cellulolytic activity. This study showed that enrichment method was effective for isolation of beneficial microbes. One hundred and seven isolates assayed exhibited ability to produce IAA about 200 µg/ml. One hundred sixty four isolates appeared solubilized of Ca-P complex and release orthophosphate. Ninety nine isolates showed ability to fix nitrogen and 24 isolates were able to degrade cellulose