HAYATI Journal of Biosciences
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Biocorrosion Behaviour of Carbon Steels by Tropical Microbes in the Presence of Corrosion-Inhibiting Bacterium
Get PDFA set of microbiologically induced corrosion was carried out on different types of carbon steels: AISI 1006 and API 5L X52, iron-oxidizing bacterium and sulfur-oxidizing bacterium, a mixed culture of Alicyclobacillus ferrooxydans SKC/SAA-2 and Aspergillus niger and Comamonas thiooxydans SKC/SAA-1, in the presence of the corrosion-inhibiting bacterium, Pseudomonas plecoglossicida. According to the immersion test experiments, weight loss of API 5L X52 was lower (0.06-0.27%) than AISI 1006 (0.14-0.32%). AISI 1006 showed more detrimental localized pitting corrosion than API 5L X52. During the longer incubation time, the corrosion-inhibiting bacterium was more homogenous and compact, which affected the specimen surface more protective characteristics. The 2-week-old biofilm effectively protected the API 5L X52, as indicated by the low amount and more negligible pitting corrosion. This study will be the first report on the biocorrosion behaviour of carbon steels using different corrosion-causing microbes in the presence of the corrosion-inhibiting bacterium
Effects of Dietary Mannan-Oligosaccharide (Mos) and Multi-Species of Bacillus on Growth and Feed Utilization in Leopard Coral Grouper Plectropomus leopardus Juvenile
Get PDFThis study assessed the growth and feed utilization in leopard coral grouper Plectropomus leopardus juvenile fed dietary prebiotic mannan-oligosaccharide (MOS) and multi-species of probiotic bacteria (Bacillus cereus BS6, B. subtilis BS3, and B. amiloliquefaciens BS4). The experiment was performed by feeding four replicates groups of juveniles weighing 3.61±0.60 g on four experimental diets, and each diet included: only MOS (PRE); the multi-species of Bacillus (PRO); a combination of MOS and the multi-species of Bacillus (SYN) and without supplementation (CON). When MOS (PRE) or the multi-species of Bacillus (PRO) was included in the diet solely, the growth of the fish was fairly good, although there was no significant difference with the control diet (p>0.05). Unexpectedly, the combined inclusion of MOS and the multi-species of Bacillus (SYN) did not increase the growth and feed utilization in Plectropomus leopardus juvenile. Presumably, MOS did not exert any favorable effects on the multi-species of Bacillus. This study suggested that no advantage was obtained when MOS and the multi-species of Bacillus were included in the diet simultaneously. In addition, the inclusion of MOS in higher levels may be necessary for better feed utilization and growth in leopard coral grouper Plectropomus leopardus
Genetic Diversity of Eight Native Indonesian Chicken Breeds on Microsatellite Markers
Get PDFIndonesia has diversity in native chickens based on phenotypes. This diversity is utilized for economic purposes such as meat, eggs, fancy, crowing, and fighting. This study aimed to determine the genetic structure of eight native Indonesian chicken breeds with microsatellite markers, the genetic distance, and inbreeding coefficient of each breed of chicken used for crossbreeding programs to obtain a positive heterosis effect for selection programs. The samples used were Arab, Merawang, Pelung, Sentul, Cemani, KUB, Black Kedu and White Kedu. Broiler chickens (Cobb) were used as the outgroup in this study. A total of 192 DNA samples from eight breeds were used in this study. A total of 24 microsatellite markers were used in this study to observe the genetic diversity of 8 native breeds. The POPGENE, Cervus, and FSTAT were used to generate the observed number of alleles, the effective number of alleles, observed heterozygosity value, expected heterozygosity value, the heterozygote deficit within the breed (FIS), gene flow (Nm), Hardy-Weinberg equilibrium, Polymorphism Information Content (PIC), and UPGMA tree. The principal component analysis (PCA) was performed using adegenet package of R software. Bayesian clustering assignments were analyzed using the STRUCTURE program. This study revealed a very close genetic relationship between seven native chickens and broilers. We also found Arab chickens separated from other Indonesian native chickens and no inbreeding in eight native Indonesian chicken breeds. In conclusion, we found two clusters among eight native Indonesian chicken breeds. Twenty microsatellite markers have a high PIC value in this study
Correlation between Stress and Eating Behaviour in College Students: A Longitudinal Study
Get PDFStress is a process that involves the perception of and response to pressure and is often related to eating behaviour. For college students, academic stress could be one factor that affects eating behaviour. So far, no longitudinal study has directly compared the same respondents’ stress levels and eating behaviours in different years of study. Thus, this study aimed to examine changes in stress levels and eating behaviour during college students’ third and final years and determine the correlation between stress levels and eating behaviour. We asked 89 undergraduate students (27 males and 62 females) to complete a questionnaire on their stress levels using the Perceived Stress Scale (PSS-10) and their eating behaviour. Our results showed that students had significantly higher stress levels during the final year than in their third year. Our results also showed that during the student’s final year, there was a significant increase in eating when feeling stressed, overeating, eating fast food, and skipping meals compared to their third year. There was also a significant decrease in healthy food consumption during the final year compared to the third year. During the third year of study, stress levels were increased by academic workload pressure; meanwhile, during the final year of study, they were affected by sex and undergraduate thesis pressure. These results indicate that differences in academic pressure in different years of study can influence stress levels and eating behaviour in college students
Morphological and Anatomical Comparison between Tetraploid Stevia rebaudiana (Bertoni) Bertoni and its Parental Diploid
Get PDFStevia rebaudiana (Bertoni) Bertoni is a perennial herbaceous plant that produces natural low glycemic-index sweeteners alternative to sugar cane. The genetic improvement of Stevia needs to be investigated to increase its productivity. Although this plant has a narrow genetic diversity, genetic improvement through polyploidization may succeed. Meanwhile, genotypic characters of tetraploid Stevia were previously reported. This study then observed the phenotypic characters of the tetraploid plants, which aimed to evaluate the morphological and anatomical characteristics of tetraploid Stevia clones compared to its wild-type parental diploid plant. Three tetraploids and one diploid clone were grown in the field for 12 weeks. The results of qualitative descriptive characters showed that the tetraploid clones B60.3H8, P1T22 and P3T5 had habitus type, shoot bud shape, leaf margin, leaf venation, shape, and type of stem, type of flower, and seed similar to the diploid parental clone. However, the quantitative characters showed that the tetraploid clones had leaf size, stem diameter, root size, length of the single flower, length of the flower stalk, and length of fruit which were more extensive than those of the parental diploid clone. The leaf color of tetraploids was a darker green, and the range of initial flowering times was earlier. This finding gives more understanding of the phenotypic and anatomical characteristics of Stevia tetraploids compared to their parental diploid plant
Revisit Study of Freshwater Sponges Eunapius carteri (Bowerbank, 1863) and a New Record of Oncosclera asiatica Manconi and Ruengsawang, 2012 (Porifera: Spongillida) in Porong River, East Java, Indonesia
Get PDFDistribution of freshwater sponges (Porifera: Spongillida) in Indonesia is currently insufficiently reported and underestimated compared to marine sponges. An inventory study on freshwater sponges in East Java after Indonesian independence in 1945 is yet to be carried out. For this reason, we reported new records of two freshwater species, Eunapius carteri (Bowerbank, 1863) and Oncosclera asiatica (Manconi and Ruengsawang, 2012) in Porong river, East Java, Indonesia. E. carteri species was originally described in Mumbai, India and its presence in Java was reported in 1927, 1928, and 1930. DNA barcoding and molecular phylogenetic analysis using mitochondrial COI was able to successfully identify our specimens as E. carteri, while analysis using the nuclear ITS markers placed our samples with other Eunapius species. Furthermore, in this study we report for the first time in East Java, Indonesia, the presence of O. asiatica. The O. asiatica species was originally described from Pong River located in Lower Mekong, Thailand. We concluded our specimens to be O. asiatica based on the morphology, skeleton, and spicule composition of the specimens that were similar to the samples recorded in Thailand. We were only successful in obtaining the COI sequence of O. asiatica. Furthermore, our samples did not group to the publicly available sequence of its congener, namely Oncosclera sp. Therefore, further molecular taxonomy and morphological analysis is needed to explore the diversity of freshwater sponges in general and to conduct species delimitation of E. carteri and O. asiatica in Java, Indonesia, and Asi
Cloning, Expression, and In Silico Analysis of Class IV Poly-(R)-3-hydroxybutyrate Genes from New Strain of Bacillus thuringiensis TH-01
Get PDFPoly-(R)-3-hydroxybutyrate (PHB) is a bioplastic derivative of polyhydroxyalkanoate (PHA) which can be synthesized by bacteria under certain growth conditions. Previous study has reported a new strain of Bacillus thuringiensis TH-01 isolated from thermite, which found to accumulate PHB. This research aimed to clone PHB biosynthesis genes from B. thuringiensis TH-01 and study its expression as well as predict the tertiary structure of the enzymes. The clone of phaA gene, which encodes PhaA, was obtained as 1182 bp. On the other hand, 2546 bp clone of phaRBC gene cluster was obtained to consist of 744 bp phaB, 1086 bp phaC, and 483 bp phaR, encoding respective PhaB, PhaC, and PhaR proteins. In silico analysis indicated that PhaA, PhaB, PhaC, and PhaR, revealed to have 393, 247, 361, and 160 amino acid, respectively. The predicted model of PhaA, PhaB, and PhaC showed dominant structure of α/β folding motif, while PhaR was dominated by a helix-loop-helix motif. The catalytic residues of PhaA were Cys88, His349, and Cys379, whereas the catalytic residues of PhaB were Ser142, Tyr155, and Lys159. These catalytic residues were identical to those residues obtained in other PHB biosynthetic enzymes reported elsewhere, confirming that our clones were of PHB biosynthetic genes
Aeromonas hydrophila AHL 0905-2 and Streptococcus agalactiae N14G as Combined Vaccine Candidates for Nile Tilapia
Get PDFIn Indonesia, the Nile tilapia (Oreochromis niloticus) is the most widely farmed and available fish for consumption. Production loss due to bacterial infection by Aeromonas hydrophila and Streptococcus agalactiae is the main problem in tilapia cultivation. This study aimed to determine the occurrence of concurrent infection of Aeromonas hydrophila AHL 0905-2 and Streptococcus agalactiae N14G in Nile tilapia based on biochemical and molecular characteristics. From the results of biochemical assay and sequence analysis of the 16S rRNA fragment, Aeromonas hydrophila and Streptococcus agalactiae were confirmed. Genes for aerolysin (417 bp), nuclease (504 bp), lipase (155 bp), and serine protease (211 bp) were found in Aeromonas hydrophila AHL 0905-2, while Streptococcus agalactiae N14G was determined as a 1b serotype group that had genes for CPS L (688 bp), CPSG (621 bp), and CPS J (272 bp). The confirmation in tilapia of Aeromonas hydrophila and Streptococcus agalactiae by PCR and sequencing is important for enabling the detection of these organisms and also for the development of a combined vaccine to tackle co-infection
DNA Barcoding of Neolissochilus sumatranus and Tor douronensis to Support In Situ Conservation of Indonesian Mahseers
Get PDFThe fishes of genera Neolissochilus and Tor are locally known as Ikan Batak or ihan in North Sumatra. They are sacred and are usually served in Batak tribe traditional ceremonies. However, their population in the wild is declining because of habitat degradation, unwise exploitation, water pollution, and the introduction of invasive species. Therefore, suitable management is needed to maintain Ikan Batak\u27s sustainability in their natural habitat, which can be conducted through in situ conservation. The habitat of Ikan Batak in the Bonan Dolok river of the Samosir Regency can potentially be developed as a conservation site. Information concerning this species in Bonan Dolok River is needed as a basis for effective in situ conservation management. Morphologically identified fish captured in Bonan Dolok River were validated using DNA barcoding of cytochrome oxidase I (COI) mitochondrial DNA segment. This study confirmed that Ikan Batak captured from Bonan Dolok River belongs to two genera, Neolissochilus and Tor. Furthermore, the phylogenetic tree construction using Maximum Likelihood showed that the specimens identified as N. sumatranus were identical to N. cf soroides, a species found in the Malaysian peninsula, Thailand, and Cambodia.  
Gynura procumbens Adventitious Root Extract Altered Expression of Antioxidant Genes and Exert Hepatoprotective Effects Against Cadmium-Induced Oxidative Stress in Mice
Get PDFExposure to cadmium (Cd) could increase of reactive oxygen species (ROS) and changes in expression of antioxidant genes. Gynura procumbens is a medicinal plant that is rich in phenolic and flavonoid compounds. The aimed of study to evaluate the hepatoprotective effect of G. procumbens adventitious root (GAR) extract against Cd toxicity, especially expression rate of hepatic antioxidant genes. Twenty-five male mice were treated as follows: P1 (control), P2 (Cd100mg/L), P3 (GAR100mg/L + Cd100mg/L), P4 (GAR200mg/L + Cd100mg/L), and P5 (GAR300mg/L + Cd100mg/L). The samples (blood and liver) were collected for analysis of malondialdehyde (MDA) levels, superoxide dismutase (SOD) and catalase (CAT) activities, and their relative gene expression were determined. The hematological assay showed Cd-treated administered with GAR extract increased the number of red blood cells (RBC), haemoglobin concentration (HGB), hematocrit (HCT), mean corpuscular volume (MCV), and mean corpuscular haemoglobin (MCH), but reduced the level of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). In addition, the GAR extract decreased the MDA production, but increased the activities of SOD and CAT. These enzymatic activities were positively correlated with their respective gene transcripts. Our study revealed that GAR extract administration showed marked hepatoprotective effects against Cd-induced oxidative stress