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Makara Journal of Science
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  This is an Open Access Journal Open Access journal
ISSN (Print) 2339-1995 - ISSN (Online) 2356-0851
Published by Universitas Indonesia Homepage  [19 journals]
  • Characterization of Cellulase Enzyme Produced by Two Selected Strains of
           Streptomyces Macrosporeus Isolated from Soil in Indonesia

    • Authors: Yati Sudaryati Soeka, Nandang Suharna, Evi Triana, Titin Yulinery
      Abstract: This study was conducted to characterize the cellulase enzymes produced by Streptomyces macrosporeus BB 32 and S. microspores KRC 21. D, which were isolated from Tanjung Pendam, Belitung Island, and from Cibodas Botanical Garden, Indonesia, respectively. The optimal activity of the enzymes was analyzed using parameters such as incubation time, pH, temperature, carboxymethylcellulose (CMC) concentration. The effect of the addition of some metal ions as activators or inhibitors was also analyzed spectrophotometrically at l 540 nm. Results demonstrated that the activity of the cellulase enzymes of S. macrosporeus BB 32 and S. macrosporeus KRC 21 D reached the optimum level after 2 and 5 days of incubation and at pH values of 8.0 and 6.0, temperatures of 35 °C and 50 °C, and CMC concentrations of 1.75% and 2%, respectively. S. macrosporeus BB 32 cellulase was activated by the cations CuCl2, MgCl2, and ZnCl2 but inhibited by NaCl and CoCl2, reducing its activity. The cellulase of S. macrosporeus KRC 21.D was activated by the cation NaCl and by the divalent cations CoCl2, CuCl2, MgCl2, and ZnCl2. S. macrosporeus BB 32 was deposited at the Indonesian Culture Collection with the collection number InaCC A454.
      PubDate: 2019-06-28
      Issue No: Vol. 23 (2019)
  • Sterol and Triterpene Profiles of the Callus Culture of Solanum mammosum

    • Authors: Silvy Juliana, Suciati Suciati, Gunawan Indrayanto
      Abstract: This study aimed to compare the sterol and triterpene profiles of two types of Solanum mammosum callus cultures, i.e., compact globular structure (CGS) and normal fine (F) calluses. The CGS callus resulted from the differentiation of the F callus culture after many years of subculturing. The growth rate, microscopic characteristics, and morphologies of the two callus types were determined and compared. Sterols and triterpenes were identified through thin-layer chromatography, gas chromatography–flame ionization detection, and gas chromatography–mass spectrometry analyses. The growth rate of the CGS callus was lower than that of the F callus. Microscopic identification revealed that thick, lignin-containing cell walls formed in the CGS callus but not in the F callus. The chromatographic analysis suggested that the CGS and F callus cultures had different sterol and triterpenoid profiles. The sterols and triterpenes produced by the CGC culture were more diverse than those produced by the F callus culture.
      PubDate: 2019-06-28
      Issue No: Vol. 23 (2019)
  • Extraction of “Quercetin-Rich” Red Onion Skin with Acetone and
           Chemical Modification using Aromatic Diazonium Salts

    • Authors: G. Manizabayo, U J Chukwu, O J Abayeh
      Abstract: The extraction of “quercetin-rich” red onion skin (red onion skin extract [ROSE]) using acetone and chemical modification with aromatic diazonium salts of aniline (AmROSE), 2-aminophenol (APmROSE), and 2-aminobenzoic acid (ABmROSE) were carried out in this study. The effects of the particle diameter of red onion skin (ROS), volume of the solvent, and percentage of acetone in the solvent mixture on the extraction yield were investigated. The solubility, color, melting point, and functional groups present in ROSE before and after modification were also analyzed. The extraction of ROS using an aqueous solvent of 50% acetone gave the highest percentage extraction yield. In addition to the C=O, OH, C-O-C, and C-O-H functional groups that were present in both unmodified ROSE (UROSE) and modified ROSE, Infrared spectra results revealed that all the modifications (AmROSE, APmROSE, and ABmROSE) showed the presence of N=N and C-N of aromatic azo compounds at 1512–1496 and 1288–1256 cm−1, respectively. The three modifications were also found to be more soluble than UROSE in all the solvents. The melting point of UROSE and its modifications was within the range of 78 °C–105 °C, which was lower than that of commercial quercetin dehydrate P-Q (300 °C–310 °C).
      PubDate: 2019-06-28
      Issue No: Vol. 23 (2019)
  • Potential of Indigenous Methanotrophic Bacteria as a Biological Control
           Agent Against Xanthomonas oryzae pv. oryzae Causing Diseases on Rice

    • Authors: Maimuna Nontji, Farizah Dhaivina Amran
      Abstract: Methanotrophic bacteria inhabit the rhizosphere and potentially inhibit the growth of pathogens. Therefore, they have potential utility as biological control agents. This study aimed to analyze 10 isolates of indigenous Methanotrophic bacteria with the potential to act as biological control agents for Xanthomonas oryzae pv. oryzae. Analysis of antagonistic activity was conducted by the direct inhibition method on media using the following parameters: the time to formation of a clear zone, the diameter of the clear zone, and the index of inhibition. The study recommended two isolates as biological control agents that can be combined to inhibit the growth of Xanthomonas oryzae pv. oryzae.
      PubDate: 2019-06-28
      Issue No: Vol. 23 (2019)
  • Blended Film from PVA and Sansevieria trifasciata Dichloromethane Fraction
           for Reducing Heat Radiation from Smartphones

    • Authors: Auliya Ilmiawati, Pujiyati Pujiyati, Asep Hidayat, Purwantiningsih Sugita, Luthfan Irfana, Budi Arifin
      Abstract: It has been reported that the lidah mertua plant (Sansevieria trifasciata) can absorb electromagnetic radiation from various electronic equipment. The current study aimed to make a film layer from polyvinyl alcohol (PVA) and a dichloromethane (DCM) fraction of S. trifasciata to reduce heat radiation from smartphones. S. trifasciata leaves were macerated using ethanol and partitioned with ethyl acetate, DCM, and n-butanol. The DCM fraction was chosen to create the film, for which PVA was also used. The blended film made from PVA and 0.02% DCM reduced heat radiation from smartphones by up to 4.4 °C starting from the first minute of use; its heat reduction remained stable until the 20th minute. Based on these results, it was determined that the active compounds in the DCM fraction are closely related to saponin-type steroids.
      PubDate: 2019-06-28
      Issue No: Vol. 23 (2019)
  • Bioconversion of Glycerol to Docosahexaenoic Acid by Thraustochytrium
           WB-02 an Indigenous Indonesian Microalga Strain

    • Authors: Witono Basuki
      Abstract: Glycerol is a by-product of the biodiesel industry, and it can be processed to produce many useful derivatives. This study is aimed at examining the bioconversion of glycerol to docosahexaenoic acid (DHA) using local microalgae. Glycerol to docosahexaenoic acid converting microalgae were obtained from the mangrove area in the coastal sea of Lampung Province. The single colony was then generated by the scratching technique in its isolation and purification process. By using 18S rDNA, a potential strain namely WB-02, was identified as Thraustochytrium sp. Gas chromatography analysis was performed to identify its product conversion. As a result, Thraustochytrium WB-02 was identified to utilize glycerol as a single carbon source and convert to DHA. A maximum DHA yield of more than 3.4 g/L was obtained when the glycerol concentration in the medium was 8%. Thraustochytrium WB-02 was regarded as a potential microalgae resource in producing DHA due to its high level of production.
      PubDate: 2019-06-28
      Issue No: Vol. 23 (2019)
  • Sequence Variability in the NRAMP1 Gene among Indigenous and Exotic
           Chicken Types

    • Authors: Abazuh Uchenna Desmond, Adekoya Khalid Olajide, Oboh Bola Olufunmilayo
      Abstract: The natural resistance-associated macrophage protein 1 (NRAMP1) gene in chickens, which exists on chromosome 7, is thought to play a significant role in disease resistance. Variations in this gene have been documented and have played crucial roles in the variations in the resistance and/or susceptibility that is expressed by individuals and different groups of animal species. In this study, the NRAMP1 gene was studied for single nucleotide polymorphism (SNP) variability between indigenous and exotic chicken breeds. The gene was amplified using the polymerase chain reaction (PCR) method and sequenced and analyzed. Six SNPs, both synonymous and non-synonymous (C3700T, G3702C, A3712C, C3714G, C3693G, and G3705T), were detected in the gene in both indigenous and exotic chicken types. One allele form was detected among all the sample animals that were studied. A phylogenetic tree revealed that the indigenous chicken type and the exotic broiler chicken type are genetically similar with respect to this gene. However, the exotic layer chicken type is genetically suggested to be distantly related to both the indigenous and broiler chicken types, indicating that the gene has probably been evolving both within and among different poultry species.
      PubDate: 2019-06-25
      Issue No: Vol. 23 (2019)
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