Keanekaragaman Spesies Lamun di Kabupaten Bangka Selatan Provinsi Kepulauan Bangka Belitung

Marine area which is planted by seagrass called as seagrass beds. Seagrass is one of the typical ecosystems in marine waters. Bangka Belitung Province is one of the areas in Indonesia that has seagrass ecosystem. This study aims to determine the diversity, density, and coverage area of seagrass beds in the waters of South Bangka Regency. The research was conducted in Tukak, Tanjung Kerasak, and Tanjung Kemirai. The data is collected using quadratic transect method and also data of physics-chemical parameters such as temperature, salinity, pH, depth, velocity and water substrate. The results of the research showed that 7 species of seagrasses in South Bangka Regency are Cymodocea serrulata, Cymodocea rotundata, Halodule uninervis, Enhalus acoroides, Thalassia hemprichii, Syringodium isoetifolium and Halophila minor. Seagrass in Lempeng waters which has the highest density is Cymodocea serrulata, about 58 ind/m2. The highest frequency of seagrass species in Tukak is Thalassia hemprichii about 1%. Seagrass species of Cymodocea serrulata has the highest cover percentage in Lempeng waters about 29.56%

Efek Konsentrasi Sublethal Fenol Terhadap Total Haemocyte Count (THC) Dan Histologi Insang Kepiting Bakau (Scylla Serata)

Hadirnya fenol yang melebihi batas ambang ke dalam ekosistem perairan dapat menjadi stresor kimia bagi organisme akuatik, termasuk juga bagi ekosistem muara oleh karena muara (estuaria) merupakan daerah pertemuan antara air tawar dari perairan sungai dan air laut sehingga berpotensi mengandung bahan kimia antropogenik. Kepiting bakau (Scylla spp.) memiliki siklus hidup yang sebagian besar berada pada ekosistem mangrove dan umum digunakan dalam studi ekotoksisitas. Total Haemocyte Count (THC) dan histologi organ insang dapat menginformasikan Perubahan histologi akibat stressor oleh karena paparan toksik, terutama fenol. Perlakuan sublethal fenol dengan konsentrasi yang berbeda terhadap kepiting bakau (Scylla serata) pada hari ke-1, hari ke-3, hari ke-5 dan hari ke-8 tidak terdapat perbedaan yang signifikan (p> 0,05) (Lampiran) terhadap rata-rata Total Haemocyte Count (THC). Namun pada hari ke-7 menunjukkan penurunan jumlah THC pada tiap perlakuan bila dibandingkan dengan kontrol (tanpa perlakuan). Perubahan histologi yang terjadi meningkat sebanding dengan konsentrasi fenol yang diperlakukan terhadap kepiting bakau (S. serata). Perubahan histologi yang terjadi adalah kerusakan struktur dari lamela insang (l) dan bagian terluar sinus lamela atau outer lamellar sinuses (ols) yang meliputi infiltrasi hemosit, hiperplasia maupun nekrosis

Purification and Characterization of Aeromonas Media Klu 11.16 Chitosanase Isolated From Shrimp Waste

Our previous study found that KLU 11.16, isolated from shrimp waste secreted chitinolytic enzymes. The crude enzyme was interesting since their chitooligosccharide was able to inhibit some pathogenic bacteria. In this study we report a purification and characterization of the chitosanase enzyme produced and the identification of the KLU 11.16. Purification of the enzyme was done two steps by ion exchange chromatography followed by gel filtration. Two out of 4 peaks from Gel Filtration step, i.e. fraction 16 and 33 were capable of hydrolyzing 100% deacetylated chitosan, indicating that both fractions contained chitosanase enzyme. The enzyme from fraction 16 had approximate molecular weight of 98.3 kDa. The enzyme worked optimally at temperature of 300C, and pH 6. Addition of Ca2+, Fe2+, K+, Na+ ions in the form of Cl2 salt and detergent Triton X-100 increased the enzyme activity, while Co2+, Mn2+ and Zn2+ ions in the same concentration decreased the enzyme acitivity. Addition of EDTA and SDS significantly decreased the enzyme activity. Molecular based identification revealed that KLU 11.16 was 99% similar to Aeromonas media

The effects of acute exposure to cadmium nitrate (CdNO3) on gambusia fish (Gambusia affinis)

The aim of this study was to assess the impact of cadmium nitrat (CdNO3) in Gambusia affinis on growth and the development of histopathological changes in gill organs and on the activity of some oxidative stress markers during a 96-hours acute toxicity test. Tests were performed on G. affinis. The average initial weight of fish used in the experiment was 3±1.2 g and the average initial total length of fish was 5.21±3.48 mm. The fish were exposed to a range of CdNO3 concentrations (1 mg/L, environmental concentration, 0.1, 0.01, 0.001 nad 0.0001 mg/L) for 96 hours. Each test on a CdNO3-treated group was performed in duplicate. There were no significant differences between the specific growth rates of fish from the test groups and from the control group. Histopathological examination revealed no pathological changes in organs of fish exposed to any CdNO3 concentration. Significantly lower CAT and SOD activity (p<0.05, p<0.01) was found in fish exposed to CdNO3 concentrations of 1, 0.1 and 0.01 mg/L compared to the control group; the control group was observed. H2O2, GSH and GPx exhibited significantly higher activity (p<0.01) in the 1, 0.1, 0.01 and 0.001 mg/L groups compared to the control group. But none of these differences were significant (p>0.05). No significance differences (p>0.05) between the control group and any experimental group were found with respect to Protease activity. The MDA level was significantly higher (p<0.01) at a concentrations of 1, 0.1, 0.01 and 0.001 mg/L compared to the control, while in the other experimental groups no significant differences compared to the control group (p>0.05) were observed. According to our results, all tested concentrations of CdNO3, including the environmental concentration, had an inhibit on oxidative stress markers and detoxifying enzymes in exposed fish, but did not affect fish growth or cause the development of histopathological changes in the fish organism. © 2019 IOP Publishing Ltd

Indonesian coral reef habitats reveal exceptionally high species richness and biodiversity of diatom assemblages

We present the results of the first ever research on biodiversity and biogeography of marine benthic diatoms from coral reefs of the tropical islands of Indonesia, including West Borneo, East Java, South Celebes, Komodo, Rinca and Flores. The sampled islands offer a broad range of coral reef microhabitats and host diatom assemblages from seaweeds, sea grass, dead corals, scrapes from other biological surfaces, sand, rocks and other solid surfaces. The results of this study are based on the light (LM) and scanning electron microscopy (SEM) identification of diatoms only. Our taxonomic analysis revealed the presence of 911 diatom taxa representing 188 genera. Biodiversity indices such as Shannon, Simpson and Evenness as well as species richness and diatom relative abundance were calculated for each sample examined. We find that these indices were higher for Indonesia than those published for tropical oceanic islands or regions from both hemispheres, e.g. Galapagos and Martinique, but comparable to Madagascar. The non-metric multidimensional analysis showed that the type of habitat from which a particular sample was taken was of greater significance in the taxonomic composition than the geographical aspect. In terms of biogeography, cosmopolitan taxa were dominant in terms of relative abundance, but species richness was higher within tropical zonal and local forms. Many taxa were identified only at the genus level, and may turn out to be new to science

Indonesian coral reef habitats reveal exceptionally high species richness and biodiversity of diatom assemblages

We present the results of the first ever research on biodiversity and biogeography of marine benthic diatoms from coral reefs of the tropical islands of Indonesia, including West Borneo, East Java, South Celebes, Komodo, Rinca and Flores. The sampled islands offer a broad range of coral reef microhabitats and host diatom assemblages from seaweeds, sea grass, dead corals, scrapes from other biological surfaces, sand, rocks and other solid surfaces. The results of this study are based on the light (LM) and scanning electron microscopy (SEM) identification of diatoms only. Our taxonomic analysis revealed the presence of 911 diatom taxa representing 188 genera. Biodiversity indices such as Shannon, Simpson and Evenness as well as species richness and diatom relative abundance were calculated for each sample examined. We find that these indices were higher for Indonesia than those published for tropical oceanic islands or regions from both hemispheres, e.g. Galapagos and Martinique, but comparable to Madagascar. The non-metric multidimensional analysis showed that the type of habitat from which a particular sample was taken was of greater significance in the taxonomic composition than the geographical aspect. In terms of biogeography, cosmopolitan taxa were dominant in terms of relative abundance, but species richness was higher within tropical zonal and local forms. Many taxa were identified only at the genus level, and may turn out to be new to scienc

Exopolysaccharide from Porphyridium cruentum (purpureum) is Not Toxic and Stimulates Immune Response against Vibriosis: The Assessment Using Zebrafish and White Shrimp Litopenaeus vannamei

Exopolysaccharides, or extracellular polysaccharides (EPS, sPS), represent a valuable metabolite compound synthesized from red microalgae. It is a non-toxic natural agent and can be applied as an immunostimulant. The toxicity test of exopolysaccharides from Porphyridium has been done in vivo using zebrafish (Danio rerio) embryonic model, or the ZET (zebrafish embryotoxicity test). The administration of extracellular polysaccharides or exopolysaccharides (EPS) from microalgae Porphyridium cruentum (synonym: P. purpureum) to shrimps Litopenaeus vannamei was investigated to determine the effect of this immunostimulant on their non-specific immune response and to test if this compound can be used as a protective agent for shrimps in relation to Vibrio infection. For immune response, exopolysaccharides were given to shrimps via the immersion method on day 1 and booster on day 8. Shrimp hemocytes were taken on day 1 (EPS administration), day 7 (no treatment), day 8 (EPS booster) and day 9 (Vibrio infection) and tested for their immune response on each treatment. The result shows that the EPS is not toxic, as represented by the normal embryonic development and the mortality data. In the Pacific white shrimps, an increase in the values of all immune parameters was shown, in line with the increasing EPS concentration, except for the differential hemocyte count (DHC). In detail, an increase was noted in total hemocytes (THC) value, phagocytotic activity (PA) and respiratory burst (RB) in line with the EPS concentration increase. These results and other previous studies indicate that EPS from Porphyridium is safe, enhances immune parameters in shrimp rapidly, and has the ability to act as an immunostimulant or an immunomodulator. It is a good modulator for the non-specific immune cells of Pacific white shrimps, and it can be used as a preventive agent against vibriosis