Jurnal Ilmiah Perikanan dan Kelautan

DNA Barcoding of Red Algae (Rhodophyta) in Ternate Island Sea, North Maluku, Indonesia

2023-11-20T10:53:54+07:00

Abstract

Ternate Island is located on the North Maluku Sea. The North Maluku Sea region includes the Wallacea area and the world’s coral triangle. One of the organisms commonly found in this sea is red algae. Study aimed to determine the red algae species by phylogenetic tree analysis based on the rbcL gene as a DNA marker. The preserved red algae tissue samples were extracted with the Geneaid GP100 DNA Extraction Kit Plant. The DNA sample was amplified and then visualized by 1% agarose gel electrophoresis. The amplicon products were sequenced and then aligned with the rbcL gene database that was available at the NCBI gene bank. The phylogenetic tree was constructed using the UPGMA method. The results showed that red algae were identified into four species: namely Gibsmithia hawaiiensis (98.65%), C_rbcL sample was identical to Amansieae sp. (91.50%), D_rbcL sample was identical to Peyssonnelia sp. (95.54%), and G_rbcL sample was similar to Portieria hornemanniI (96.15%). Based on phylogenetic tree analysis, Gibsmithia hawaiiensis from North Maluku is closely related to species from Raja Ampat, West Papua, Indonesia, followed by the Philippines species. Special findings were found to carry out phylogenetic reconstructions that can answer inter-species kinship. The general finding is that the markers used can be used for phylogenetic construction. Phylogenetic construction of Peyssonnelia sp. in North Maluku is related to species from South Africa. North Maluku's Portieria hornemannii is closely related to a species from Korea.

Highlight Research

This study provides initial information about the DNA barcoding of red algae.
Important for management purposes and determining the status of red algae in the future.
This scientific information also provides an understanding of the relationships among red algae species in the world's oceans.
Global warming has changed the temperature of seawater and affected the population of marine organisms.

Isolation, Identification, and Pathogenicity of Potential Probiotics Isolated from Intestinal Coconut Crab (Birgus latro Linnaeus, 1767)

2023-12-01T18:32:25+07:00

Abstract

The supply of coconut crabs (Birgus latro Linnaeus, 1767) has been sourced from capture in the wild. Development efforts in aquaculture have succeeded in producing eggs. However, further development with larval maintenance failed because it was constrained by a low survival rate. This study aimed to identify the potential probiotic bacteria in coconut crabs. Coconut crab samples were collected from Moor Island, South Patani District, Central Halmahera Regency, North Maluku Province, Indonesia. The intestines of coconut crabs were taken as much as 1 g, then ground on a porcelain dish and added to Tri-Salt. The scouring liquid was taken in 0.1 ml and spread on a petri dish containing Nutrient Agar. The isolated used were marked with BL1, BL2, BL3, BL4, and BL5. Molecular identification was performed with sequencing and then analyzed using the Basic Local Alignment Search Tool (BLAST). The selection of isolates from the gastrointestinal tract of coconut crabs showed that the bacteria obtained were Enterobacter tabaci (BL1), Enterobacter hormaechei (BL2), Bacillus horneckiae (BL3), Pseudomonas stutzeri (BL4), and Acinetobacter variabilis (BL5). Further testing revealed that the bacteria A. variabilis (BL5) is a probiotic isolate in coconut crabs.

Highlight Research

The intestinal bacteria from coconut crabs identified were E. tabaci, E. hormaechei, B. horneckiae, P. stutzeri, and A. variabilis.
The E. tabaci strain BL1, E. hormaechei strain BL2, B. Horneckiae strain BL3, and P. stutzeri strain BL4 are pathogenic bacteria.
The A. variabilis strain BL5 is potential probiotics bacteria.
The A. variabilis strain BL5 showed a better survival rate than other isolates.

DNA Barcoding of Cardinalfish (Apogonidae) in Gilimanuk Bay, Bali, Indonesia

2023-05-02T10:29:35+07:00

Abstract

The Apogonidae is estimated to consist of nearly 300 fish species, most of which inhabit coral reef areas. The lack of distinctive body markings and overlapping species distribution makes species assignment challenging. Therefore, this study aimed to delineate species and establish barcoding reference databases of Apogonidae in Gilimanuk Bay (Bali, Indonesia) using the Cytochrome Oxidase I (COI) gene of the mitochondrial DNA. A total of 22 fish tissue samples were extracted with 10% Chelex solution. BLAST analysis was performed and genetic differentiation between species was calculated. The phylogenetic tree was constructed using the Maximum Likelihood method and tree visualization was generated using iTOL V5. The morphology and genetic identification results based on the mitochondrial COI gene revealed eight species of seven genera, and one species was new to GenBank online database. This study was the first-ever addition of COI sequence for Ostorhinchus hartzfeldii into the GenBank database. The average K2P genetic distance within species and K2P distance between genera within the family were 0.60% and 19.10%, respectively. The mean genetic distance between genera within the family was 31.8-fold higher than the mean genetic distance within species. The phylogenetic tree showed that each sample resided in a distinct cluster, which indicates that DNA barcoding is a reliable and effective approach for species delimitation in Apogonidae fishes.

Highlight Research

Eight species of cardinalfish in Gilimanuk Bay were delineated using the barcoding method.
This study provides the first nucleotide sequence for Ostorhinchus hartzfeldii in GenBank online database.
The phylogenetic tree showed that each sample resided in a distinct cluster, indicating that the barcoding method efficiently differentiated at the species level.
The mean genetic distance between genera within the family was 31.8-fold higher than the mean genetic distance within species.

Effects of Iodine Treatment on the Development of Eggs and Larvae of Rabbitfish (Siganus guttatus Bloch, 1787)

2023-11-02T08:14:31+07:00

Abstract

Iodine is proven to be an effective disinfectant for fish eggs and is commonly used in a hatchery to improve hatching and survival rates. However, tolerance to iodine can vary in different fish species, and it is essential to determine the optimal concentration to ensure successful hatchery production. This study investigated the optimum concentration and exposure time to iodine during incubation to improve rabbitfish larvae’s hatching and fertilization rate from 4/2022 – 8/2022 in Thua Thien Hue, Vietnam. The study consisted of two experiments: Experiment 1 focused on different iodine concentrations: 0 ppm (C1), 50 ppm (C2), 100 ppm (C3), and 150 ppm (C4). Experiment 2 explored three exposure times: 10 minutes (T1), 20 minutes (T2), and 30 minutes (T3) to increase the fertilization, hatching, and survival rates at five days post-hatching. Data were compiled, analyzed, and compared by ANOVA using SPSS ver. 22.0. The results showed that 100 ppm iodine concentration at 20 minutes of exposure resulted in the optimum hatching, fertilization, and survival rates of S. guttatus during artificial reproduction. In the future, integrated solutions in the use of iodine solution for egg treatment and natural food supplementation at the larval stage should be recommended to improve the efficiency in artificial hatchery production of Rabbitfish.

Highlight Research

The concentration and incubation time of rabbitfish (Siganus guttatus) eggs affect the production efficiency of fingerling fish.
Iodine concentration of 100ppm for 20 minutes is the best to treat fish eggs before incubation.
The fertilization rate of eggs, hatching rate, and survival rate of larva after 5 days of hatching when washing by iodine concentration of 100 ppm was 86.44 ±84%, 96.14 ± 1.05%, 58.65 ± 7.60% respectively.

Effect of Ultrasonic Assisted Extraction with Ethanol for Removing Lipid on Catfish (Pangasius sp.) Skin as a Collagen Source and Its Characteristics

2023-06-30T10:01:06+07:00

Abstract

Fish skin is rich in collagen (80%-90%). However, catfish (Pangasius sp.) skin has a high lipid content, which can reduce the quality of collagen. Therefore, treatment is needed to remove the lipid using ultrasonic assisted extraction (UAE) with ethanol. Hence, the aim of the present study was to remove lipid content from catfish skin as a raw material for collagen by using UAE with different concentrations of ethanol (25, 50, and 75%). The research was conducted in three stages: removing impurities, collagen extraction, and characterization of collagen. The result exhibited that UAE-ethanol treatment was capable of removing up to 85.6% of lipid content, and the produced collagen had the potential to be utilized as an alternative source of collagen based on its properties.

Highlight Research

Ethanol could be used as extractor of lipid from catfish skin of Pangasius
Ultrasonic assisted extraction could increase efficiency of lipid extraction from catfish skin.
Fish skin of Pangasius sp. has a potential source for collagen.
Collagen from skin of Pangasius sp. has a good characteristic with high protein content.

Front Meter Vol 16 No 1

2024-01-27T16:44:15+07:00

Effect of Dayak Onion (Eleutherine bulbosa (Mill.) Urb.) on the Immune Response and Gene Expression of Nile Tilapia (Oreochromis niloticus) Infected with Aeromonas hydrophila

2023-05-27T16:34:32+07:00

Abstract

Dayak onion (Eleutherine bulbosa (Mill.) Urb.) has the potential to be an immunostimulant to benefit fish health. This study aimed to evaluate the effectiveness of dietary supplementation with the powder and crude ethanol extracts of Dayak onion on the hematology and immune response parameters of Nile tilapia challenged with Aeromonas hydrophila. The research used a completely randomized design with six treatments and three replications. Nile tilapias were fed with Dayak onion (w/v) consisting of powders of 5% (P5), 10% (P10), and 15% (P15), while crude extract was 0.5% (E05) and given during rearing for 30 days. Positive control (C+) and negative control (C-) were used without Dayak onion. Nile tilapia in treatment C+, P5, P10, and P15 were injected with A. hydrophila 10⁶ CFU mL⁻¹, while that in treatment C- was injected with phosphate buffered saline (PBS) intramuscularly. The results showed that the dietary with 15% powder and 0.5% crude extract significantly improved the hematology and immune response parameters compared to the control after the challenge against A. hydrophila (P<0.05). Dayak onion supplementation effectively increased the health status based on hematology and immune response parameters of Nile tilapia against A. hydrophila infection.

Highlight Research

Dayak onion has significant potential to improve nonspecific immunity in fish.
Dayak onion improves hematology and immune response of Nile tilapia.
Dayak onion can significantly regulate the immune system against A. hydrophila infection.
Dayak onion significantly increases the production of the gene expression of IL-1β and TNF-α.

Growth and Metabolite Enhancement of Acidophile Euglena sp. Isolated from Indonesia under Different Photoperiod Cycles

2023-09-26T08:13:18+07:00

Abstract

Euglena sp. is a unicellular, flagellated microalga considered one of the most promising microalgal feedstock species for biofuels. Reducing the level of liquid waste pollutants can be done biologically by using microalgal organisms. Its metabolites, including lipids, proteins, carbohydrates, and pigments, are appropriate for producing biorefinery products such as biodiesel and jet fuels. They can be isolated from extreme environments, such as highly acidic and ammonia-rich environments, that are not conducive to their proliferation. This study sought to determine the effect of the photoperiod or (light: dark) cycle (24 L:0 D, 12 L:12 D, 14 L:10 D, and 16 L:8 D) on the growth, biomass, metabolite content consisting of lipids, carbohydrates, and proteins, and the rate of CO₂ uptake by Euglena sp. As stated previously, the study was conducted by cultivating Euglena sp. on a laboratory scale with four photoperiod regimens. The results indicated that optimal growth, biomass content, and metabolite content were obtained with a 24 D:0 L lighting cycle. The control treatment (24 L: 0 D) had the highest biomass productivity (0.032 g.L^-1.day^-1± 0.004), lipid content (0.387 g.L^-1± 0.031), protein content (0.542 mg.Ml^-1± 0.007), carbohydrate content (0.409 x10⁴ g.L^-1), chlorophyll a (6.237 g.L^-1± 0.184), chlorophyll b (2.838 g.L^-1± 0.253), and total carotenoid (1.566 g.L^-1± 0.105). Full light illumination (24 L:0 D) was significantly producing carotenoid content, including phaeophytin a, phaeophytin b, violaxanthin, 9’-cis-neoxanthin, dino xanthin, and fucoxanthin.

Highlight Research

The growth rate was higher when Euglena was cultivated under continuous illumination.
The biomass productivity of Euglena increased significantly under continuous illumination.
The metabolite content of Euglena (lipids, proteins, and pigments) was higher in continuous illumination.

Effect of Dietary Canarium indicum L. on the Growth, Health, and Resistance of Asian Seabass Challenged with Vibrio alginolyticus

2023-04-10T18:15:27+07:00

Abstract

Canarium indicum offers the potential of usage in aquaculture. This study aimed to evaluate the utilization of C. indicum on growth performance, health, and resistance of Asian seabass Lates calcalifer challenged with Vibrio alginolyticus. The study employed a completely randomized design with seven treatments, namely positive control (K+), negative control (K-), vitamin control (KVit), antibiotic control (KAnt), doses of 5 g kg^-1 (D05), 10 g kg^-1 (D10), and 20 g kg^-1 C. indicum (D20). The test feed was prepared with a coating method and fed for 30 days. On the 31st day of rearing, a challenge test was conducted by injecting V. alginolyticus intramuscularly at 10⁶ CFU mL^-1. The results showed that C. indicum treatment for 30 days had a significantly different effect (P<0.05) on weight gain and average daily growth, while KVit and KAnt treatments were not different from the control. After the challenge test, all doses of C. indicum treatment, as well as KVit and KAnt treatments, showed survival significantly different (P<0.05) from that of the positive control, which ranged from 88.89% to 95.56% and was not significantly different (P>0.05) from the negative control. The survival rate condition is identical to the cumulative survival condition which shows the highest mortality found in the positive control. The administration of C. indicum at a dose of 5 g kg^-1 to 20 g kg^-1 improved the growth performance and prevented V. alginolyticus infection.

Highlight Research

C. indicum significantly increases the growth of Asian seabass.
C. indicum significantly enhances the immune response to V. alginolyticus infection in Asian seabass.
C. indicum can prevent V. alginolyticus infection as it resulted in a higher and cumulative survival than the positive control.
C. indicum can be developed as an immunostimulant for the prevention of vibriosis in Asian seabass at doses of 5 g kg^-1 to 20 g kg^-1.

Exploring the Resources Governance Connectivity of Cultural Ecosystem Services: Evidence in Tanjung Lesung SEZ Tourism, Banten Province, Indonesia

2023-05-26T07:54:20+07:00

Abstract

The existence of the utilization of the Tanjung Lesung Special Economic Zone (SEZ) as connectivity, interaction relationships, and the balance of resource governance influence cultural ecosystem service. This research aimed to map out the social-ecological system components of coastal and marine cultural ecosystem services. The focus is on examining the connectivity network between resource governance (RG) components such as resource actors (RA), resource units (RU), and resource systems (RS). The data obtained were analyzed using the stages of social-ecological network analysis. The results show a significant influence and strong interaction between resource governance (RG) components and other components. The presence of institutional structures and typologies is a crucial component that serves as a guideline for SEZ management influenced by actor centrality through links. Several performance indicators are still lacking based on the interaction conditions, indicating the need for strategies to strengthen governance. However, a particular challenge that needs attention is the implementation of every governance strategy formulation. Cohesion among stakeholders in enhancing resource governance performance with the surrounding community is paramount. Improvement can be achieved through strong collaboration to ensure the sustainability of coastal and marine cultural ecosystem services.

Highlight Research

The components of the social-ecological system of cultural coastal and marine ecosystem services can be identified and analyzed in a case study of a special economic zone.
The complexity of the social-ecological system was analyzed using a network perspective approach.
Centrality analysis was used to determine the magnitude of influence of each component in the system.
The performance condition of governance can be determined using analysis of the resource governance interactions.

Sustainable Pangasius Aquaculture Management Strategy using Multidimensional Scaling (MDS) and Analytical Hierarchy Process (AHP) in Tulungagung Regency, East Java, Indonesia

2024-01-19T09:34:01+07:00

Abstract

Aquaculture activities in Tulungagung Regency provide livelihoods for 12,050 households. Therefore, ensuring the sustainability of Pangasius aquaculture activities is crucial for the welfare of fish farmers. This study aims to analyze the sustainability of existing Pangasius aquaculture businesses in Tulungagung Regency, East Java, Indonesia, and to create a sustainable Pangasius aquaculture policy strategy. This quantitative study used Multi-Dimensional Scaling (MDS) and Analytical Hierarchy Process (AHP) analyses to determine the sustainability status of Pangasius aquaculture based on five dimensions: ecological, economic, social, institutional, and technological infrastructure. Among these dimensions, two are less sustainable, particularly infrastructure technology and the economy.

Highlight Research

The author mentioned four highlights from their research:

Tulungagung Regency is East Java Province's major pangasius producer.
MDS can assess sustainability across multiple dimensions.
AHP enables the prioritization of strategies that must be implemented.
The Pangasius aquaculture company in Tulungagung Regency is currently in a sustainable state.

Spatial and Temporal Variability of Mixed Layer Depth (MLD) in Eastern Indian Ocean (EIO): 1998-2020

2023-03-27T08:28:01+07:00

Abstract

Mixed Layer Depth (MLD) plays an important role in various aspects of oceanography. MLD has a characteristic parameter value that is uniform with depth. MLD has an important role for local, regional, and global phenomena. Indonesia, which is surrounded by the East Indian Ocean, will be directly influenced by the dynamics of MLD. This study aimed to analyze seasonal variability and MLD between years. Mixed layer depth data from the ARMOR3D Dataset Copernicus-Marine Environment Monitoring Service was used for MLD analysis with a threshold of 0.2^oC for temperature. Wavelet analysis showed that MLD variability in the eastern Indian Ocean spans from intra-seasonal to interannual scales. Time series analysis showed a complex relationship between MLD and SST in the annual and interannual periods which indicates a different process. The MLD monthly climatology at point 90E, 0 showed the depth of mixed layers is deeper during the east monsoon (JJA-SON) ranging from 50-65 m compared to the west monsoon (DJF-MAM) which has a range of 20-40 m. Spatially the MLD in the south of the equator is deeper than in the north. Interannually, MLD is heavily influenced by the Indian Ocean Dipole. MLD depth is deeper in nIOD with a maximum depth in the range of 100 m compared to pIOD. MLD with maximum depth in the strong nIOD phase is around the equator and the pIOD phase is south of the equator. The study also showed that inter-annual variability in regions around the mainland showed a stronger response.

Highlight Researh

ARMOR3D data has fairly good accuracy as evidenced by data validation
In general, EIO is influenced by intra-seasonal, seasonal and inter-annual variability
The shallowing and deepening of the MLD are strongly correlated with the wind speed associated with the annual cycle
IOD has a strong role in MLD which looks significantly different, especially when nIOD and pIOD

Oxygenase Enzyme Activity and Compound Profile in Hydrocarbon Bioremediation by Pseudomonas aeruginosa and Rhodococcus erythropolis Consortium

2023-12-01T10:58:01+07:00

Abstract

Hydrocarbon contamination is one of the most significant environmental problems, including in the marine environment. Several methods, such as chemical and physical remediation, have been constructed to remediate pollutants but remain side effects and have a relatively high cost. Bioremediation is an alternative method for degrading contaminants due to its eco-friendliness and low cost. During bioremediation, the enzyme oxygenase is produced by bacteria to degrade pollutants. However, the oxygenation enzyme's activity and compound profile during this bioremediation process are still sparsely explored. This study aimed to analyze oxygenation enzyme activity and compound profiles during the hydrocarbon bioremediation process by bacterial consortia of Pseudomonas aeruginosa and Rhodococcus erythopolis. The materials of this research were the oxygenase enzyme activity, compound profile, and amount of BOD and COD during the bioremediation process. The results showed that the monooxygenase enzyme has activity between 0.257 and 3.859 U/mL. Meanwhile, the dioxygenase enzyme has activity between 0.579 and 5.402 U/mL. The final incubation compound profile found that Hexadecanoic acid methyl ester (C₁₇H₃₄O₂) decreased by up to 47.66%. Moreover, BOD and COD reductions were 68.59% and 67.51%, respectively. This study concluded that oxygenation enzymes were produced to degrade pollutant compounds during the hydrocarbon bioremediation process. Further research is needed to improve the effectiveness of bioremediation by enhancing enzyme activity.

Highlight Research

The potential of hydrocarbon-degrading bacteria (Rhodococcus erythropolis and Pseudomonas aeruginosa) for pollutant degradation in the marine environment.
Enzyme activity of hydrocarbon-degrading bacteria and degradation profile of pollutants.
The dynamics of BOD and COD during the bioremediation process.

Integration of Tetraselmis chuii and Artemia sp. Culture in Industrial-Scale Salt Production

2024-01-27T15:31:59+07:00

Abstract

The common technique of traditional salt production in Indonesia is seawater evaporation technology, which uses sunlight to produce salt crystals from seawater. However, in general, the applied technology only produces salt with about 80% NaCl and water contents >7%, impurities >2%, and other contaminants. This produced salt is not suitable to be used as industrial salt. This study aimed to determine the effects of liquid organic fertilizer Gracilaria sp. addition into the culture media of Tetraselmis chuii on Artemia sp. growth, to identify the profile of length, weight, and survival rate of Artemia sp., and finally attempted to uncover the contribution of Artemia sp. in impurity mineral absorption and NaCl content improvement. The results of the study showed that the density of T. chuii based on the concentration of liquid organic fertilizer Gracilaria sp. was significantly different (p<0.05) in each treatment. T. chuii cultivation using liquid organic fertilizer Gracilaria sp. 16 mg N/mL resulted in the highest density on the culture days. However, the studies showed that there was no significant effect (p>0.05) on the weight and length gain of Artemia sp. The research conducted can support the downstream use of products from engineering research in the field of technology to increase the added value of salt products and be part of the contribution to the achievement of the 14th SDG on life below water.

Highlight Research

Integration of chuii and Artemia sp. culture in salt production could improve NaCl contents by up to 97% and reduced impurities of sulfate and magnesium.

The result of the first phase of this study is the density of chuii. This finding is useful to find out the effects of Gracilaria sp. liquid organic fertilizer administration as a source of nitrogen that improves the growth of T. chuii.

The highest density of T. chuii resulted from a treatment receiving the dose of 16 N mg/L Gracilaria sp. liquid organic fertilizer with > 5 x 10⁶ cells/mL. This finding indicates that the administration of 16 N mg/L Gracilaria liquid organic fertilizer into the culture medium provided a source of nitrogen and phosphorus for the metabolism of T. chuii.
The results of the mineral content test on Artemia sp. show the largest percentage change in Mg²⁺ > SO₄^2- > Cl^- > Na⁺. The densities of Artemia sp. showed a positive trend of increasing levels of Mg²⁺ and SO₄^2-, which coincided with decreasing levels of Mg²⁺ and SO₄^2-in seawater media.
The results of NaCl content measurement in water with Artemia sp. culture integration show salt with excellent quality of 97% that met the criteria of industrial salt. The contribution of Artemia sp. to improving the quality of salt products is interesting and has the potential to serve as an alternative to the traditional salt-farming system that is currently practiced.

The Livelihood Vulnerability of Vannamei Shrimp Culture as the Impact of Climate Change in Banyuwangi Regency, East Java Province, Indonesia

2023-11-29T09:32:16+07:00

Abstract

During Covid-19 outbreak, the production of the Vannamei Shrimp (Litopenaeus vannamei) actually increased and even increased the value of Indonesia’s exports. The existence of shrimp culture is closely related to the nature of the surrounding environment, especially climate change. Climate change has a potential impact on aquaculture production, which affects livelihoods that depend on aquaculture. This study aims to analyze the development of sea surface temperature (SST) and high tides over the last 10 years and to analyze the vulnerability of the vannamei shrimp culture to climate change. This research uses a descriptive method. Data were collected through direct interviews with respondents, while the model was a structured interview. Secondary data were obtained from satellite imagery through geographic information systems, and from literature. Data analysis used spatial analysis with Geographic Information Systems (GIS), and vulnerability analysis was carried out to build the Livelihood Vulnerability Index matrix. The results show that climate change affects the development of sea surface temperature (SST) and high tides on the coast of Banyuwangi Regency, East Java Province, Indonesia. It is proven that during the last 10 years SST and high tide data shows that it fluctuates every year, SST between 27.75-29.6°C, the high tide between 1.47-1.57 m. Changes in SST affects high tide, and both become variability that affects vannamei shrimp culture. The results of the vulnerability analysis show that vannamei shrimp culture livelihoods in Banyuwangi Regency are categorized as vulnerable to climate change, with a value of 3.30 (3.34 vulnerability threshold).

Highlight Research

1. Climate change affecting livelihood vulnerability of vannamei shrimp culture

Effect of Nano Chitosan Concentration and Storage Temperature on the Physical Characteristics of Edible Films of Black Mangrove Starch-Chitosan

2023-05-15T22:19:33+07:00

Abstract

Edible films made from chitosan and starch materials have several physical limitations, particularly in terms of tensile strength and elongation. To address these limitations, glycerol and sorbitol are often added as plasticizers during the production process. Chitosan has also been reported to have plasticizing properties and can serve as an alternative through its modification into nano-sized particles, thereby increasing its reactivity. Therefore, this study aimed to characterize the physical properties of edible films made from black mangrove (Rhizophora mucronata) fruit starch and chitosan by adding nano chitosan suspension at different storage temperatures to determine the best treatment. A completely randomized factorial design was used, and the data obtained were analyzed using Analysis of Variance (ANOVA) at a 95% confidence level with IBM SPSS statistics 25. The treatments used included the addition of nano chitosan suspension (A) at various concentrations of 0%, 25%, 50%, and 75% with storage (B) for 0 days, 9 days at room temperature, and 9 days at cold storage (± 5⁰C) in triplicates. The significant treatments were then further tested using Honestly Significant Difference (sig < 0.05). The results showed that the addition of nano chitosan suspension with storage method affected the physical properties of the edible films. The edible film made from black mangrove fruit starch-chitosan with the addition of nano chitosan (50%:50%:75%) stored at cold temperature for 9 days had the best physical properties to be applied as a package for fishery products (fillets) based on De Garmo analysis.

Highlight Research

Nano chitosan can be applied as plasticizer in making edible film of black mangrove starch-chitosan.
The concentration of nano chitosan and storage temperature influenced the thickness, tensile strength, elongation, young modulus, and water resistance of edible film.
The edible film made from Black mangrove starch - chitosan with the addition of 75% concentration of nano chitosan when stored at cold temperature (5 ⁰C) for nine days can increase tensile strength, young modulus, elongation, and water resistance.
Components of edible films interact less with one another intermolecularly due to nano chitosan, which encourages the creation of hydrogen bonds between polymer chains.

Optimizing Coastal Management: A Comprehensive Value Chain Analysis Approach for Sustainable Economic Development in Java, Indonesia

2023-08-21T18:22:55+07:00

Abstract

Coastal areas have become an important part of Indonesia's evolving economy, with a variety of commercial activities taking place. The island of Java has both northern and southern coastal areas, each with its own distinctive characteristics and products. The studies about coastal development through its product value chain are still limited. This study aimed to determine the value chain of fishery products in Java to provide recommendations for enhancing coastal management. For the northern coast, milkfish and ariid catfish from Juwana Coast (Pati Regency, Central Java) were selected, while Whiteleg Shrimp from Mendit Coast and Trisik Coast of Kulon Progo Regency, Yogyakarta were chosen to represent the southern coast. The study involved 48 respondents, including small and medium-sized enterprises (SMEs), farmers, fishermen, wholesalers, middlemen, retailers, restaurants, and consumers. The analysis techniques used in this study included Porter’s value chain, Hayami’s added value, Return/Cost (R/C) Ratio, and marketing margin analysis. The results of the study revealed that the products followed various channels in the value chain, with longer chains leading to higher prices for the end consumers. The findings also indicated that processed and creatively packaged products tend to command higher prices and generate greater profits. Coastal management should not only focus on upstream activities but also consider downstream processes to increase the value of coastal products. Efforts to enhance coastal management should consider key actors and government interventions through developing the coastal local products.

Highlight Research

The coastal area of Java Island makes a significant contribution to the local economy.
The supply chain of Whiteleg Shrimp, Ariid Catfish, and Milkfish involves various actors who play important roles in maintaining the distribution of coastal products.
Value chain analysis reveals opportunities to increase and improve the quality of products to enhance their worth.
It is necessary to enhance coastal management by involving local institutions, the government, and the private sector.

Social Structure Analysis in Management of South Sumatra Inland Waters

2023-09-03T14:49:31+07:00

Abstract

The social structure of inland fisheries communities tends to place powerful elites in important positions, while local fishermen are subordinate actors. Patronage is a form of social relationship that describes the unequal social structure between these actors. This research aimed to analyze social structure in the inland waters of South Sumatra in the practice of the Lebak Lebung and River Auction (L3S) in OKI District. To achieve this goal, a constructivist paradigm with qualitative research methods was employed, and the sample comprised 39 informants selected as subjects. The data analysis was conducted in three distinct stages, namely data reduction, presentation, and drawing conclusions. The results showed that the regulation of open access for all parties in the local government regime after 1982 created an institutionalized social relations structure where the government, investors, traders, middlemen, and non-fishing actors dominated compared to the fishermen. The participants in this social landscape strived to accumulate capital to enhance their competitiveness within the L3S domain. A patronage system was implemented with middlemen assuming the role of patron and the fishermen acting as their clients. The current institutional social structure has created an unfair distribution of resource benefits for fishing workers. The novelty theories were found in the working relations of the inland waters community of South Sumatra, namely stratified distribution of rights, dual status, multi-stage patronage, and the positive function of patronage for chief fisherman. Further research should be conducted to research policy revitalization and develop strategic inland water management models.

Highlight Research

The author mentioned 3 highlights from their results research:

Auction system in inland waters in South Sumatra presents an unfair distribution for fishermen.
Structure of the working relationship formed is an asymmetric patron-client relationship but with novel theories such as the stratified distribution of rights model, dual status, multi-stage patronage, and the positive function of patronage.
An imbalance in local access to auction objects due to their weak ability to accumulate capital.

Xanthophore Distribution of Nemo (Amphiprion ocellaris) Skin Based on various Concentrations of Carotenoid Sources

2023-07-31T12:36:59+07:00

Abstract

The decreased color intensity of Nemo is related to the amount of carotenoid concentration in the xanthophore of Nemo’s skin. Therefore, efforts are needed to maintain stable carotenoid production. Tomato is one of the most abundant carotenoid producers. The utilization of carotenoids can maintain the morphological color of aquatic organisms. This study aimed to analyze the effect of carotenoid compounds on total carotenoid content, the size, and distribution of xanthophores on Nemo skin. A total of 60 Nemo with an average initial weight of 0.84±0.14 g and an average length of 2.95±0.08 cm. The research was conducted using a completely randomized design (CRD), consisting of four carotenoid concentrations in addition to fish pellet, 0%, 0.5%, 1%, and 1.5% with three replications. The results showed that the optimum dose of carotenoid compounds in increasing the total carotenoid content in nemo fish skin is 1.5%. Carotenoids added to the fish feed affected the distribution and maturity of xanthophore. However, it did not affect the size of the xanthophore.

Highlight Research

Nemo contains three types of pigment cells, namely melanophores, xanthophores, and iridophores.
Carotenoid supplementation is related to xanthophore in fish skin
The pigment pattern is determined mainly by the number, size, and distribution of different cell types
xanthophores were not found in the histology HE (hematoxylin-eosin) staining method in fish skin.

The Gonadal Maturity and Gene Expressions of Female Giant Freshwater Prawn (Macrobrachium rosenbergii) after Dietary Administration of Medroxyprogesterone Acetate

2023-05-02T10:31:31+07:00

Abstract

One of the problems in giant prawn cultivation is female giant prawns laying eggs during rearing. They will incubate their eggs for three weeks so that the energy from the expected feed for growth is used for egg development and other reproductive activities. Giving MPA hormone to giant prawns either by injection or oral could inhibit gonadal maturation and increase growth rate. The maturation process of the prawn ovary consists of the activation of some complex cellular mechanisms involving genes that regulate the stages of oocyte development. This study aimed to evaluate the response of gonadal maturity and the expression of the MrvWD-Kazal gene in giant prawns fed with a diet containing MPA hormone. The design used in this study was a completely randomized design with four treatments and five replications. The treatments were feeding a diet added with MPA with a concentration of 0 mg.kg^-1 feed as control (K), 50 mg.kg^-1 feed (P1), 100 mg.kg^-1 feed (P2), and 150 mg.kg^-1 feed (P3). MPA hormone at a concentration of 50-150 mg/kg feed could inhibit the gonadal maturation of female prawns. In 100 mg/kg of feed concentration showed the lowest gene expression level, indicating an inhibition of gonadal maturation molecularly. The administration of MPA hormone through the feed is a recommended method of aquaculture because it is more applicable and effective than by injection, even though it has a non-uniform impact on each individual.

Highlight Research

Administration of MPA hormone through the feed to female giant freshwater prawns can inhibit the level of gonad maturity.
Expression of von Willebrand factor D (vWD) – Kazal gene were analyzed in different levels of prawn maturity
Gonadosomatic index and gonadal histology confirmed that different levels of administration of MPA hormone through the feed could affect the gonad development.
The administration of MPA hormone through the feed is a recommended method for aquaculture because it is more applicable and effective to inhibit early maturation of prawns.

The Use of Vegetation Indices on Temporal Mangrove Condition: A Case Study on Timbulsloko and Bedono, Demak

2023-11-30T09:12:32+07:00

Abstract

Mangrove forests in Timbulsloko and Bedono have very dynamic conditions, due to tidal flooding and land subsidence that occur in these areas. Meanwhile, mangrove forests in the Timbulsloko and Bedono Village play an important role in preventing abrasion which often occurs in these areas. The importance of the mangroves function in this area makes it crucial to monitor their condition. Monitoring the condition of mangroves can be done by looking at their density through the vegetation index. Therefore, this study aimed to determine the best vegetation index to be used in the Timbulsloko and Bedono villages to monitor mangroves in 2016-2018, 2020, and 2022. The method in this research consisted of two stages, namely sentinel 2 image processing and the field survey. Image processing was used to determine the condition of mangroves based on several vegetation indices. Meanwhile, data collection in the field was utilized to validate several vegetation indices used in this study and conducted with the hemispherical photography method. Linear regression analysis was used to determine the most suitable vegetation index to be applied in the study area. The study found that NDVI vegetation index had the highest accuracy value, followed by SAVI, EVI, and MVI. The use of NDVI to see the changes in mangrove conditions showed an increase in the total area in each category. So, it can be concluded that the area and density of mangrove forests in the Bedono and Timbulsloko villages increased every year.

Highlight Research

Mangroves in each region have different canopy density values.
The use of the mangrove vegetation index will produce different accuracy values in different areas.
LAI has a very strong relationship with the NDVI.
The addition of area in the sparse mangrove category can be an indication of mangrove planting at the most recent time.
In general, the research outcome will be valuable recommendation for mangrove rehabilitation in current target area.

Back Meter Vol 16 No 1

2024-01-27T16:45:36+07:00