HAYATI Journal of Biosciences
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The Acute Single and Mixture Toxicity of Paraquat Dichloride and Deltamethrin to Guppy (Poecilia reticulata)
Get PDFAlthough herbicide and insecticide contamination of surface waters normally occurs in the form of mixtures, the toxicity interactions displayed by such mixtures have only rarely been characterized. This study evaluated the acute effects of single pesticides (paraquat dichloride and deltamethrin, tested in their commercial formulations Gramoxone 276 SL and Decis 25EC) and their equitoxic mixtures on the survival of adult male guppy fish (Poecilia reticulata). Mixture toxicity was evaluated against the reference models of Concentration Addition (CA) and Independent Action (IA). In the single treatments, the 72h LC10 and LC50 values were 1.5 and 6.0 mg a.s. L-1 and 0.53 and 3.6 µg a.s. L-1 for paraquat dichloride and deltamethrin, respectively. The equitoxic mixtures showed significant paraquat dichloride-deltamethrin antagonism, both based on the CA and the IA model, without significant dose-level dependent deviations
Quality Improvement of White Pepper with Processing through Optimizing the Ratio of Starter Culture from Acetobacter sp., Bacillus subtilis, and Bacillus cereus
Get PDFFermentation process using known microbial species can be exploited for the processing of white pepper. It is expected to generate quality of white pepper in a short period soaking time. This research aimed to study characteristics of white pepper through a fermentation process by addition of combination isolates of Acetobacter sp., B. subtilis, and B. cereus. After threshing, 2 kg of fresh pepper berries was soaked in water mixed with starter culture. The experiment used a completely randomized design, two replications. The treatment consisted of: A) starter culture ratio of Acetobacter sp.: B. subtillis: B. cereus (A1 = 0:0:0; A2 = 1:1:1; A3 = 2:1:1; A4 = 1:2:1; and A5 = 1:1:2) and soaking time (B1 = 5 and B2 = 7 days). Fermented pepper was decorticated, washed, and dried. The best treatment was fermented for 7 days with the combination isolates of Acetobacter sp., B. subtilis, and B. cereus with ratio 2:1:1. This condition produced white pepper in fulfilling in requirement of SNI standards with piperine and essential oil contents and TPC of 5.95%, 2.95% and 1.1 x 102 CFU/g, respectively. This process is expected to generate high quality of white pepper in a short soaking time
The Effect of Feed Supplementation with Fermented Red Seaweed (Kappaphycus alvarezii) on Growth and Survival of White Shrimp (Litopenaeus vannamei) Post-Larvae Culture
Get PDFThis study was aimed to investigate the effect of novel shrimp diet supplemention with fermented red seaweed Kappaphycus alvarezii on growth and survival of whiteleg shrimp (Litopenaeus vannamei) post-larvae culture. The research consisted of three consecutive steps: (1) preliminary study on Kappaphycus alvarezii fermentation, (2) feed formulation and proximate analysis, (3) performance test of commercial feed (C), commercial + 0.5% K. alvarezii (EF1), and commercial + 1.5% fermented K. alvarezii (EF2). Following 15 days of feeding, the highest biomass, specific growth rate and survival were achieved in EF2 treatment (1.60±0.21 g, 10.88±0.86%/d, 91.67±1.53%), significantly different from control (0.99±0.09 g, 7.72±0.63%/d, 47.00±5.00%) (p<0.05). Overall, this study suggested that the dietary supplementation of 1.5% fermented K. alvarezii can enhance the growth and survival of whiteleg shrimp during the nursery phase
Diversity and Abundance of Phytoplankton in the Coastal Waters of South Sulawesi
Get PDFPhytoplankton are primary producers that can be used as seawater condition indicators. Certain phytoplankton can proliferate, causing harmful algal blooms (HABs). The coastal waters of South Sulawesi, Indonesia are under pressure from land-based processes and activities resulting in inputs of organic and inorganic materials. This study analysed phytoplankton diversity and abundance in coastal waters around South Sulawesi. Phytoplankton were sampled and seawater parameters (salinity, temperature, turbidity, pH, nitrate concentration) measured in-situ at six stations around seven major river estuaries in three seaways (Makassar Strait, Flores Sea, Gulf of Bone). Phytoplankton taxonomic composition, abundance and indices of diversity (H’), evenness (E), and dominance (D) were analysed. Phytoplankton from 31 species and three classes (Bacillariophyceae, Cyanophyceae, Dinophyceae) were identified. Phytoplankton abundance and community structure differed significantly between sites and seaways but were not significantly correlated with water quality parameters although Dinophyceae abundance correlated significantly with observed pollution levels. Phytoplankton abundance was strongly influenced by the Dinophyceae, especially Ceratium furca, a potential HAB species; Cyanophyceae had the strongest influence on species richness but least on community structure. C. furca abundance was strongly correlated negatively with species richness, H’ and E, and positively with D, indicating negative impacts of this species on phytoplankton communities
Evaluation of Bacterial Biofilm as Biosensor for Detecting Phenol, Catechol, and 1,2-dihydroxynaphthalene
Get PDFMonitoring of water quality from the presence of polyaromatic hydrocarbon (PAHs) compounds and its derivates are important for keeping the healthy aquatic environment. Some of those derivates are phenol and several related compounds sharing simmilar structures. This reseach aimed for the detection of those phenol and several similar compounds monitoring due to PAHs degradation. Three identified bacterial isolates of Pseudomonas aeruginosa, Staphylococcus sciuri, and Bacillus amyloliquifaciens were selected based on their phenol degradation characters. On physiological properties all three isolates were observed to degrade several hydrophobic substances such as for naphthalene and anthracene. Yet, genetic analysis indicated that the phenolic degradating oxygenase gene was detected only in the P. aeruginosa and S. sciuri. Applying those isolates for biofilm as biosensor showed a sufficient analytical performance such as their limit of detection between 0.1-0.5 μM
Waterbird Foraging Habitat Selection in Balikpapan Bay: Water Depth and Patch Area as Important Factors
Get PDFBalikpapan Bay is one of the wetlands providing potential foraging habitat for waterbirds in Indonesia. Potential habitat loss due to oil industry expansion, recent waterbird occurrence, and co-occurrence of two closely related species with similar foraging characteristics led to habitat selection. Habitat selection could be affected by food as an intrinsic factor and extrinsic factor, for example, accessibility to the physical and biological components of the habitat. This study aimed to measure the foraging habitat selection, identify significant habitat quality parameters for the habitat selection and predict the foraging habitat selection model. We used one-zero sampling for collecting foraging habitat selection data, corer sampling for prey data, and collecting the abiotic environment, and Generalized Linear Modelling (GLM) to build the model. We identified four species as the migrant Little Egret (Egretta garzetta), Great Egret (Ardea alba), Purple Heron (Ardea purpurea), and Lesser Adjutant (Leptoptilos javanicus). All species, except Purple Heron, selected foraging habitats. A simple mathematic model of foraging habitat selection was significantly affected by two factors: water depth and patch area. A large patch area may provide primary prey abundance for waterbirds, while a low water depth level may give easy access to the prey
Evaluation of Tuberculosis Vaccine Candidate, pcDNA3.1-rpfD using Mycobacterial Growth Inhibition Assay (MGIA)
Get PDFResuscitation-promoting factor D (RpfD) is a protein involved in the resuscitation of dormant bacteria. A new tuberculosis vaccine carrying the rpfD gene has been successfully constructed, pcDNA3.1-rpfD. It was demonstrated that this vaccine exhibits cellular and humoral immune responses. Therefore, within this study, the efficacy of this new vaccine candidate was evaluated using mycobacterial growth inhibition assay (MGIA). MGIA is a functional assay that measures the complex host immune response, peripheral blood mononuclear cell (PBMC) and splenocyte from BALB/c mice against mycobacteria. With BACTECTM MGITTM 960 automated system, the effect of vaccination on bacterial growth was reported as a time to positivity (TTP) in hours. The mean of TTP from the vaccinated group (both pcDNA3.1-rpfD and BCG) was higher than the negative control group. These results suggest that pcDNA3.1-rpfD may be effective in controlling tuberculosis growth and may provide a clue for the development of the tuberculosis vaccine. In addition, despite previous evidence that IFNγ was essential for tuberculosis immunity, IFNγ (interferon gamma) production was found not to be correlated with mycobacterial inhibition. Therefore, these findings offer an alternative method to evaluate vaccine candidates than the assessment using IFNγ only
The Development of In Vitro Culture Sterilization Method of Gametophyte Explant Lopholejeunea sp.
Get PDFIn vitro cultures of leafy liverworts are still facing significant challenges due to high-level of explant contamination. The sterilization process can easily damage the structure of liverwort after exposure to the disinfectant. This study was to determine the concentration and time exposure of commercial bleach as a disinfectant to suppress contamination using the gametophyte culture of Lopholejeunea sp. The experiment consisted of control and six treatment combinations of commercial bleach with concentration 0.5, 0.75, and 1% (v/v), and exposure time (60 and 90 seconds). The type and location of contamination, the color of the explants after sterilization, and response after 30 days were observed. The results showed that the 0.75% bleach with 60 and 90 seconds exposure time had a lower contamination until the 7th day of culture. The most common type of contamination is bacteria and fungi that arise from the explant. Despite the contamination, it did not inhibit shoot formation. Further studies still needed to determine the type of fungicides and antibiotics with the most potent concentration and exposure time should be tested to obtain an axenic and viable culture of liverworts Lopholejeunea sp
In Vitro Germination and Flowering of Dendrobium capra J.J. Smith, An Endemic Orchid of Java
Get PDFDendrobium capra is an Indonesian endemic orchid species that live in Java. It grows on low altitude with warm climate. D. capra has beautiful small yellow greenish flower that grow in raceme inflorescence. This orchid faces a threat in its natural habitat due to having a long life cycle and a forestry main commodity as a main host thus categorized as Appendix II on CITES list. To address that problem, ex situ conservation approach using in vitro culture method is necessary. Germination enhancement effort using complex organic substances found that 200 ml/l tomato extract gave best germination result. Analysis on D. capra plantlet growth also showed that MS medium produced better plantlet size than NP, VW and KC medium. Supplementing medium with a combination of NAA and TDZ has also successfully induced early flowering within 11 month of culture period. This information is important to achieve successful in vitro culture of D. capra for various purposes
Antibacterial Activity of Flavonoids from Ethyl Acetate Extract of Milk Banana Peel (Musa x paradisiaca L.)
Get PDFInfectious diseases caused by Staphylococcus aureus and Escherichia coli can be treated by milk banana peels (Musa × paradisiaca L.). This study aims to reveal the antibacterial activity of milk banana peel ethyl acetate extract against Staphylococcus aureus and Escherichia coli, and to identify their active compounds. Extraction was conducted by maceration at room temperature, followed by partition. Separation was carried out by column chromatography with mobile phase of chloroform: ethyl acetate (7.5:2.5) and stationary phase of silica gel 60. Antibacterial assay was performed by well diffusion method and identification of active compounds was analyzed by UV-Vis spectrophotometry and LC-MS/MS. Extraction of the peel powder produced methanol extract, partition of the methanol extract resulted n-hexane, ethyl acetate, n-butanol, and water fractions. Antibacterial activity assay shows that ethyl acetate extract was the most active to inhibit the growth of both bacteria. Separation with column chromatography resulted 5 fractions. Identification of the most active fraction with UV-Vis showed that the isolate gave maximum absorption at λ 339.00 nm (band I) and λ 262.00 nm (band II) which were thought to be flavonol (3-OH substituted). Analysis with LC-MS/MS shows that the most active fraction contained 3-methacrylate flavonols and 3-(furan- 2yl) acrylate flavonols