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Screening and Optimization of Cellulase Production of Bacillus subtilis TD6 Isolated from Takifugu rubripes Fish
No full textCellulase enzymes have attracted considerable attention in recent years due to their great biotechnological and industrial potential. Cellulase enzymes provide a key opportunity for achieving tremendous benefits of biomass utilization through the bioconversion of the most abundant cellulosic material into the simplest carbohydrate monomer, glucose. Nowadays, the sources of cellulase-producing bacteria have been broadened into the presence of symbiotic bacteria in herbivorous animal and also from marine. Takifugu rubripes or known as Puffer fish is a unique poisonous vertebrate but nevertheless is considered a delicacy in Korea. The diet of the puffer fish includes mostly algae. This dietary habit considers Puffer fish as host of cellulase-producing bacteria, especially on its gut. In the present study an attempt has been made to search for the cellulolytic bacteria in the gut of Takifugu rubripes. Fifty five microorganisms have been isolated using 1% (w/v) carboxymethyl cellulose (CMC) as substrate. Congo red dye test and DNS method were then used for screening the extracellular cellulase activity of the strains. Among them, TD6 strain has shown the highest performance in term of cellulase activity. In order to evaluate the optimum culture condition of the isolate TD6 for cellulase production, the strain was grown at various temperatures, pH, carbon sources, and nitrogen sources. Under optimum condition, the maximum specific activity of 2.13 U/mg protein was achieved after growth the strain with 1.5% CMC at 45ºC pH 6 for 3 days, respectively. Based on 16S rRNA gene analysis it is proposed that the strain was identified as Bacillus subtilis. 
Micropropagation of Tetramolopium klossii (Moore) Mattfeld, Endemic Subalpine and Alpine Plant Species to New Guinea
No full textThe protocol of micropropagation of Tetramolopium klossii (Moore) Mattfeld through adventitious shoot proliferation was established. This is the first report of T. klossii tissue culture. Seeds were surface-sterilized by dipping them in 10% of ethanol for 1 min followed by soaking in 1% of sodium hypochlorite for 10 min. The sterile seeds were germinated on MS medium solidified with 8 g/l of agar, supplemented with 20 g/l of sucrose. Two-month old seedlings formed some shoot clumps on MS solid medium without addition of any plant growth regulators. Small clumps containing 4-6 adventitious shoots were used for shoot proliferation on MS solid medium containing 0; 0.1; 0.5; 1.0 and 2.0 mg/l of BAP (benzylaminopurine) or kinetin. The results showed that medium MS without cytokinins (control treatment), and the addition of 0.1 or 0.5 mg/l of BAP was more effective for shoot proliferation compared to the medium with addition of BAP at higher concentration and the addition of kinetin. In further subcultures, multiple shoots grown on MS medium without cytokinins was more vigorous than that of shoots grown on other media, so that the shoots were ready for rooting. Medium containing 0.5 mg/l of BAP was the best for maintaining multiple shoot formation. Shoots formed roots on MS medium containing half strength of macro nutrients. 
Alkane Degradation and Detection of Mono-xygenase Gene from Alcanivorax sp. from Jakarta Bay
No full textAlkanes is a major component of crude oil that can be hydrolized by enzyme alkane monooxygenase from bacteria. Nine oil-degrading bacteria were analyzed their capability to degrade alkanes (pristane and paraffin). The result of growth test on paraffin and pristane were showed that 9 isolates could be divided into two groups. First group (BL09, BL31 and BL45) could degrade both paraffin and pristane, and second group (BL01, BL06, BL44, BL057, BL058 and BL071) preferred to degrade paraffin than pristane. Three isolates (BL09, BL31 and BL45) have activity to decrease paraffin and pristane until less 50% remain. Based on homology analysis of 16SrRNA gene sequences showed that isolates No. BL09, BL31 and BL45 were identified as Alcanivorax sp. and the partial sequences of the alkB gene from those three isolates are showing 66-68% of identity compare with some mono-oxygenase gen from database of genbank. 
Tissue Culture Propagation of “Hausa potato” (Solenostemon rotundifolius (Poir) JK Morton)
No full textWe have developed an effective plant propagation method of „hausa potato‟ through shoot proliferation in vitro, acclimatization in the greenhouse and transplantation of the plantlet on the individual media container for planting material production. The shoot cultures were initiated from shoots that grew from tuber collected from the field, disinfested using standard method and transferred to MS medium with 1 mg/l of BA for shoot proliferation. The proliferating shoots were then subcultured to MS medium with no growth regulators to induce rooting and enlarge the shoot. The plantlets were acclimatized in a plastic box containing medium of a mixture of cocopeat, sands, rice husk charcoal and top soil covered with plastic film to maintain humidity. The plantlets survived at 85% and almost 100% grew into planting materials ready for transplanting in the soil. The planting materials survived in the field and produced tuber normally.
Segregation Analysis of Transgenic Rice Plants cv Rojolele Harboring cry1B Gene and Plant Selection for Potential to Yellow Stem Borer
No full textTransgenic rice plants harboring resistant gene to yellow stem borer, cry1B gene had been obtained. However, the cry1B gene in second generation of transgenic rice lines still segregating following Mendelian ratio 3:1. For further use in the breeding programs, it is important to ensure that the gene is dominant gene and the plants are homozygous for cry1B gene. Selection of homozygous transgenic rice lines containing cry1B gene at third, fourth and fifth generation had been conducted by PCR. The presence of cry1B gene was determined by showing the PCR product of 1.9 kb. Segregation analysis proved that six transgenic rice lines i.e. 3R7.8.15.1, 3R7.8.15.9, 3R7.8.15.10, 3R7.8.15.15, 3R7.8.15.21, 3R7.8.15.29 are homozygous lines for cry1B gene. Moreover, bioassay studies at vegetative stage on six homozygous transgenic rice lines showed that these transgenic rice lines are potential resistant to yellow stem borer comparing with non-transgenic plants, with the score of 0 (indicated no symptom) for six transgenic lines and score of 9 (more than 60% damaged tillers ) for non-transgenic plants. However, to confirm the efficacy of cry1B gene to yellow stem borer in natural condition, confined field trial in endemic area of yellow stem borer should be conducted.
Detection of Keto Synthase (KS) Gene Domain in Sponges and Bacterial Sponges
No full textSponges are sources of various useful natural products. The natural compounds derived from sponges are mostly complex polyketide. The polyketide synthase genes (PKS) is responsible for the biosynthesis of complex polyketides. During this research, we detected ketosynthase (KS) gene domain from 10 species of marine sponges, collected from Mediterranean Sea (Aplysina aerophoba, Petrocia ficiformis, Axinella damicornis, Axinella veronicas, Crambe crambe) and North Sea (Halichondria panicea, Haliclona xena, Haliclona oculata, Suberites massa, Ephydatia fluviatilis). We also detected KS gene domain from 12 bacterial sponge isolated from H. panicea. We used a PCR-based approach to detect the ketosynthase (KS) gene domain of Polyketosynthase (PKS) genes. Our result showed that the sponges and the bacterial sponges are mostly KS positive (700 bp). The presence of the PKS gene indicates the ability of the sponges to produce bioactive compound and potential natural product. The presence of the KS domain in both of the sponges and the bacterial sponges might also indicate that the bacterial sponges involved in the biosyntesis of secondary metabolite of the sponges. 
Antioxidant, Antibacterial, and Antidiabetic Activities of Roselle (Hibiscus sabdariffa) Extracts
No full textHibiscus sabdariffa L., also referred to as roselle, is commonly utilized in the pharmaceutical and food industries. Roselle contains bioactive compounds such as phenolics, alkaloids, tannins, flavonoids, saponins, and organic acids, which have pharmacological properties, such as antioxidant, antibacterial, immune booster, antidiabetic, anti-inflammatory, and anti-hypertensive properties. There are many studies regarding the pharmacological activities of roselle extract and its applications. However, there has been no research to study the effectiveness of the solvent in testing roselle petal extracts against antibacterial, antioxidant, and antidiabetic activities, simultaneously. This research used two kinds of polar solvents, dH2O and ethanol, with various concentrations for antibacterial activity test by five pathogenic bacteria, for antioxidant test by the DPPH method, and for antidiabetic test by the alpha-glucosidase inhibition method. The result showed that the ethanol extract of roselle had higher antibacterial activity compare to the roselle water extract. Antioxidant activity of roselle ethanol extract at 20% concentration had the highest activity 69.75 ± 0.002%; while, the 100% concentration of roselle water extract had the highest antioxidant activity 138.73 ± 0.013%. antidiabetic activity of roselle ethanol and water extract at 100% concentration had the highest activity 1,195.44 ± 0.007% and 1,552.49 ± 0.069%, respectively
In Vitro Induction of Tetraploid Pummelo ’Nambangan’ (Citrus maxima (Burm.) Merr.) by Colchicine Treatment Using Germinated Seed, Shoot Tip and Cotyledonary Node As Explants
No full textTetraploid citrus are important for interploidal hybridization to create triploid seedless citrus. Colchicine is the most commonly used as antimitotic agent to induce polyploid plants. Tetraploid induction by colchicine in Pummelo ‘Nambangan’ was conducted in vitro using different types of explants. The aim of this research was to induce tetraploid pummelo ‘Nambangan’ by colchicine treatment using germinated seed, shoot tip and cotyledonary node as explants. Tetraploid shoot induction was conducted by soaking germinated seeds, shoot tips and cotyledonary nodes in 0.1 % colchicine for 1, 3 and 5 hours. Regenerant shoots were grown on MS medium and their growth was observed after four weeks in culture. Ploidy level was determined using flow cytometry analysis. Stomata density, length and width of stomatal guard cell were also recorded. The results showed that shoot elongation was inhibited by colchicine treatment. Soaking of shoot tip explants in 0.1 % colchicine for 1 hour resulted in 66.66 % of putative tetraploid shoots. Compared to diploid shoots, tetraploids had lower stomata density but bigger in guard cell size.