HAYATI Journal of Biosciences
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Taxonomic Profiling of Microorganisms Inhabiting Two Solar Salterns that Produce High- and Low-Quality Salts
Get PDFThe contribution of halophilic microorganisms to the quality of salts produced in solar salterns has recently been recognized but not clearly understood. Using metagenomic 16S rRNA gene sequencing approach, we showed the microbial composition difference between the Tuban crystallization pond (CP-Tuban) that produces low-quality salt and CP-Sampang as a representative solar saltern that yields high-quality salt. Dominant classes in both traditional salterns were represented by γ-proteobacteria and halobacteria that occurred at higher prevalence in CP-Sampang. Microbial taxa, including beneficial genera, in CP-Sampang were more diverse and abundant compared to CP-Tuban. Among 180 genus-level OTUs identified in CP-Sampang, 127 of them were considered unique due to their absence in CP-Tuban. Higher levels of dissolved oxygen (DO) and nutrient (phosphate, nitrate, and ammonia) in the seawater reservoir (SR) of Sampang may contribute to more diverse phytoplankton genera, which could support the growth of beneficial heterotrophic microbes that positively affect the salt quality of the CP-Sampang. Low number of Dunaleilla sp. in both CPs do not seem to influence the quality of salts produced. The outcome of these comparative studies provides new insights into the contribution of diverse microbial taxa in correlation with physico-chemical parameters and phytoplankton communities to the high quality of salts produced in traditional solar salterns. The presence of beneficial genera in the enriched microbial cultures could provide an important basis for further applications, such as improving the quality of salt produced and producing unique compounds and enzymes
Social Networking Sites and Empathy Among Adolescents in Indonesia
Get PDFSocial networking sites (SNSs) have increased in number and popularity for more than a decade especially for adolescents. Previous studies conducted in western countries have stated that using SNSs could exert positive and negative effects on various aspects of psychosocial development, one of which is empathy. The relationship between SNSs use and empathy has remained unclear, especially in Indonesia. Therefore, the present study aims to determine the relationship between SNSs and empathy on adolescents in Indonesia. This study recruited 1,638 students from junior and senior high school with ages ranging from 12 to 19 years randomly across several provinces in Indonesia. Data collection was carried out by administering online questionnaires to participants consists of informed consent, demographic data, intensity of SNSs use during the past week with the Social Networking Time Use Scale (SONTUS) method, and questions about empathy with the Adolescent Measure of Empathy and Sympathy (AMES) method. Our result showed that higher frequency of using SNSs significantly positive correlated with cognitive empathy, affective empathy, and sympathy among adolescents in Indonesia, which is similar to previous studies, so this may be a general pattern in adolescence. The connections made by SNSs is believed to increase feelings of humanity (sympathy) and also empathy to other humans
Sequence-Structure Based Comparison of Structurally Homologous Thermophilic and Mesophilic Polyethylene Terephthalate (PET) Hydrolases
Get PDFProtein structure has a direct impact on thermostability. Deviations in the primary sequence can affect structural changes, leading to alterations in thermostability properties. However, the molecular basis of protein thermostability is unspecified; thus, elucidation of key factors that role particular protein thermostability is required when engineering proteins to be thermostable. To address this challenge, the amino acid composition, hydrophobicity/hydrophilicity ratio, cysteine bridges, and intrinsic features of two structurally homologous but different thermostability, poly(ethylene terephthalate) hydrolase (PETase) were compared. According to the findings, thermostable and thermolabile PETases have similar folds, compactness, and disulfide bridges. Interestingly, an abundance gap of aromaticity, hydrophobic cluster area, polar amino acid and hydrogen bond network compositions demonstrated dominant trends of variations for both PET hydrolases, indicating a pivotal role of these features in the thermostability of PET hydrolase. Furthermore, increased hydrophobic amino acid frequency in the inner surface of thermostable proteins contributed significantly to thermostability by forming more internal hydrophobic interactions and a less hydrophobic patch. There are no consistent trends in insertions and deletions between both PETases. Taken together, these observations demonstrate that hydrophobicity and hydrogen bond networks are essential factors in thermostability of thermostable PETase
Leclercia adecarboxylata C12, The Newly Isolated Cellulose-degrading Bacteria from Indonesian Coffee Pulp
Get PDFCulturable cellulose-degrading microorganisms were collected from Arabica coffee pulp in East Java, Indonesia. Fifty isolates were obtained, and thirty-three isolates showed hydrolyzing zone on Carboxy Methyl Cellulose agar plates after Congo-Red staining. The highest specific CMCase activity was observed by isolates C12, identified as Leclercia adecarboxylata based on 16S-rRNA gene sequence analysis. SDS-PAGE of Leclercia adecarboxylata C12 cellulase revealed two bands with a molecular mass of 95.49 and 81.28 kDa, respectively. Activity gel analysis showed the cellulolytic ability of Leclercia adecarboxylata C12 cellulase by clear zone formation. The optimal CMCase activity was achieved at 50°C and pH 9, and the activity retained 47% of its initial activity after incubation at 50°C for 90 minutes. The purified enzyme remains stable from pH 5 to 10, with 77% of its maximum activity. The activity of CMCase was stimulated by the presence of K+, Ca2+, Mg2+, and Fe3+, while SDS and EDTA reduced its activity. The current study shows that the thermostable-alkalophilic cellulase produced by Leclercia adecarboxylata C12 is very promising for industrial applications
Alkaline Phosphatase Activity of Plant Growth-Promoting Actinomycetes and Their Genetic Diversity Based on the phoD Gene
Get PDFActinomycete is one of the beneficial bacteria groups inhabiting rhizosphere soil. They can promote plant growth through various mechanisms. In the previous study we have isolated rhizosphere actinomycetes from maize rhizosphere with direct plant growth promotion characters. The aims of the present study were to analyze the ability of maize rhizosphere actinomycetes to solubilize phosphate, determine alkaline phosphatase activity, and study their genetic diversity based on phoD gene. Thirteen rhizosphere actinomycete isolates were able to solubilize phosphate at concertation range 55.84±2.27 mg/L to 144.48±5.71 mg/L. The activity of extracellular alkaline phosphatase was exhibited by all maize rhizosphere actinomycetes isolates in various level ranging from 0.08 mU/mL to 0.51 mU/mL. The phoD gene, one of the three homologous genes which encode alkaline phosphatases, was successfully detected in all isolates and identified as alkaline phosphatase D of Streptomyces spp. The partial phoD sequences of the isolates were located within metallophosphatase domain of alkaline phosphatase D. Alignment analysis showed that the deduced amino acid sequences of PhoD were mostly conserved in the isolates and Streptomyces spp. Essential residues involved in the active core arrangement of PhoD which binds metal ion cofactors were conserved. Constructed phylogenetic tree showed that the isolates were divided into two groups within PhoD cluster. PhoD of the isolates and Streptomyces spp. had closer relationship to purple acid phosphatase compared to other homologous PhoA and PhoX which form separate cluster. Generated three-dimensional structure model of partial PhoD had high similarity to alkaline phosphatase D of Bacillus subtilis (2YEQ) and showed overlapping structure based on super-positioning analysis
Morphology and Anatomy of Endemic Fish Leptobarbus melanopterus (Cyprinidae) in Danau Sentarum National Park Kapuas Hulu Regency
Get PDFOne of the endemic freshwater fishes in Danau Sentarum National Park (DSNP) is Leptobarbus melanopterus which has high economic value for both commercial and collection purpose. However, the overfishing of L. melanopterus running over decades with harmful catch tools is worried could contribute to the population decline in the future. At the same time, this species has never been cultured and fishermen catch directly in the habitat on a daily basis. This research was aimed to identify the morphological and anatomical characters of L. melanopterus. All samples were collected from three different sites in DSNP and measured its morphological and anatomical sizes manually. The results showed that the length of mandibula barbel was the distinguishing character between females and males, with loading score of 0.81. Most meristic variables showed no difference between two sexes. In terms of anatomical measurements, L. melanopterus females had larger gill sizes than males, including gill raker, gill arch and fill filament. Our findings signify the thorough morphological and anatomical sizes of L. melanopterus which are important in identifying fish stock, growth pattern and sexual dimorphism for future culture management
Molecular Identification, GC-MS Analysis of Bioactive Compounds and Antimicrobial Activity of Thermophilic Bacteria Derived from West Sumatra Hot-Spring Indonesia
Get PDFThermophilic bacteria are a source of bioactive compounds that have many benefits for human life. One of them is as a source of antimicrobials. This research aimed to identify and characterize the promising thermophilic bacterial isolates by analyzing bioactive compounds and their potential as antimicrobial agents. Thermophilic bacteria with the code LBKURCC were taken from the collection of the Biochemistry Laboratory of the University of Riau. Forty-four purified strains of thermophilic bacteria were tested for antimicrobial ability. These thermophilic bacteria were taken from hot springs located in the Sumatra provinces of West Sumatra and Riau. Strain LBKURCC218 isolated from Rimbo Panti hot springs in West Sumatra was chosen to further investigate antimicrobials production. Isolates of hot spring bacteria that produced the highest antimicrobial were identified by comparing the similarity of the 16S rRNA gene sequences. BLAST result and phylogenetic tree showed that the selected thermophilic bacterial strain was similar to Bacillus paramicoides with the similarity index of 99.93%. Analysis of bioactive compounds of the ethyl acetate extract of liquid cultures of B. paramycoides LBKURCC218 showed the best producer of antimicrobial compounds compared to other isolates. The most identified compounds from the ethyl acetate extract were Dodecanoic acid, representing 23.62% of the total compounds, followed by 11-Dodecanoic acid at 17.84%. Ethyl acetate extract of B. paramycoides LBKURCC218 has a high inhibition zone against Escherichia coli, Staphylococcus aureus, and Candida albicans
Population Analysis and Genetic Structure of Two Kazakh Cattle Breeds Using 150K SNP
Get PDFKazakh white-headed and Auliekol breeds are mostly spread through Kazakhstan and are animals with dual purpose productivity directions including meat and milk. Kazakh native cattle breeds are still largely unexplored based on the genetic markers and are of great interest in the country. In this study, we for the first time applied high-density SNP genotyping for two indigenous cattle breeds to study genetic diversity, population structure and relationships with the different foreign breeds. Using of GGP Bovine 150K SNP array the principal component analysis (PCA), populations estimates of the genetic structure (ADMIXTURE), genetic diversity and distances (Fst), and phylogenetic tree showed that the Kazakh white-headed and Auliekol breeds have certain separate genetic structure that differ from European and Russian cattle breeds The two of these Kazakh cattle breeds have their genetic background according to observed results as distinct breeds. The obtained results will be aided in the development breeding system and conservation programs of the Kazakh white-headed and Auliekol breeds of beef cattle in the Kazakhstan
Crude Oil Biodegradation Potential using Acinetobacter baumannii CYA20 and Bacillus subtilis CYA27 from the Bekasi Coast, Indonesia
Get PDFThe pollution of coastal areas caused by oil spills is an environmental issue that needs further attention. Crude oil contains persistent organic pollutants (POPs) that are difficult to degrade. This study aimed to isolate bacterial strains capable of degrading crude oil from the Bekasi coast through bacterial isolate characterization and crude oil biodegradation tests using a crude oil-enriched microcosm model. Two strains with higher TPH degradation values were selected among the isolated bacteria, namely CYA20 and CYA27, which specifically showed values of 46% and 66%, respectively. These strains were tolerant to NaCl concentrations of up to 4% and 12%, respectively, and they were also tolerant to pH values ranging from 5 to 9 and temperatures between 10°C and 50°C. Both strains were shown to utilize POPs, such as phenanthrene and fluorene, produce biosurfactants, and exhibited an emulsification activity in paraffin ranging from 0.373 to 0.533. Phylogenetic analyses identified these bacterial strains as Acinetobacter baumannii CYA20 and Bacillus subtilis CYA27, respectively. The results of this study indicate that these isolates could be developed as biodegradation agents for the bioremediation of crude oil-contaminated environments
Metabolite Bioactive Contents of Parkia timoriana (DC) Merr Seed Extracts in Different Solvent Polarities
Get PDFParkia roxburghii G.Don seeds have popular folkloric ethnomedicinal use in the treatment of many diseases especially in Indonesia. Methanol, distilled water, n-hexane, and ethyl acetate extracts from the seeds of Parkia roxburghii were assayed for secondary metabolism quantitative, antioxidant, antidiabetic and antibacterial and activities as well as determined the presence of phytochemical constituents. The extracts were investigated for antioxidant possession by DPPH free-radical (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2’ Azinobis (3-ethylbenz-thiazoline-6-sulfonic-acid) scavenging ability, Antidiabetic potential was invitro assayed by α-amylase inhibition and α-glucosyde inhibition while antibacterially by applying the disk diffusion procedure, as well as refined for the attendance of bioavailable phytochemical components. The result showed the existence of phytochemical components in diverse extracts could attribution free scavenging, antidiabetic and antimicrobial activities. The qualitative results all extracts of Parkia roxburghii seeds have expressed the presence of alkaloid, flavonoid, steroid, terpenoids, saponins and tannin whereas, methanol, distilled water, and n-hexane extracts expressed the presence of anthraquinones, The entire phenolic contents were examined as attested by the Follin-Ciocalteu methods, which varied from 43.82 - 137.42 mg GAE/g. The entire flavonoid compounds were measured with aluminum chloride colorimetric procedure, which varied from 20.42 – 45.90 mg QEDW/g. The total phenolic compound were measure Follin Ciocalteu which varied from 43.82-137.42 mg/g. The alkaloid, saponin, tanic acid, terpenoid and cardiac glycoside quantitative were measured with spectrofotometri UV-VIS which varied from 16.34 – 48.90 mg for alkaloid. The Saponin content varied 1.76 – 16.04 mg/g. Tanic acid which varied 0.21 – 7.29 mg/g. Terpenoid which varied 50.12 – 91.02 mg/g. Cardiac glycoside which varied 7.24-36.53 mg/g. The potential antioxidant were measured with ABTS and DPPH method, the methanol extract is the potential antioxidant. Antidiabetic potential were measured with alfa amylase and alfa glucosyde inhibition, the best antidiabetic is methanol extract. The potential antibacterial and antifungal was the methanol extract for Eschericia Coli and Candida Albicans. The conclusion established the tremendous perspective of the Parkia roxburghii seeds as another option fountain of food supplement, as well as drug components