{"title":"Design and Performance of Scaled-Up Microwave Dryer for Seaweed Drying","authors":"A. Hakim, W. T. Handoyo, A. Prasetya","doi":"10.15578/squalen.v15i3.454","DOIUrl":"https://doi.org/10.15578/squalen.v15i3.454","url":null,"abstract":"Direct sunlight is commonly used to dry fresh seaweed by artisanal farmers in Indonesia due to its low cost and ease of handling. Nevertheless, this method poses some drawbacks such as lengthy duration, weather dependency and quality degradation. The application of microwave technology in food processing has progressed dramatically, including in the drying process. The microwave drying method is more efficient and can shorten the processing time. This study aimed to describe a large-scale microwave dryer (MD) design and performance to assist the fresh seaweed drying process. The design concept applies microwave energy with a volumetric heating feature to accelerate the seaweed drying process without damaging its functional groups. The MD dimensions were 2410 (l) x 270 (w) x 210 (h) mm with a dryer capacity of up to six kilograms, an enlarged cavity and multiple magnetrons. The main components of the MD were cavity, air circulation system, drying system and control system. According to the performance testing, the MD’s optimum performance was at a power level setting of P7 and six kilograms load. At this setting, we obtained a dried seaweed with a moisture ratio of 0.68±0.05, drying rate of 30.29±1.32 g/min, specific energy consumption of 3.96±0.08 MJ/kg H2O and energy efficiency of 58.45±2.65%. The total power of the P7 setting operation required 2.00 kW. Fourier-Transform Infrared (FTIR) spectra showed that the functional groups of the dried seaweed were unaltered.","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76230547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Karim, Masudur Rahman, E. J. Alice, M. Amanullah, Md Akhtar Hossain, M. Islam
{"title":"Quality of Refrigerated Tilapia (Oreochromis niloticus) Slices under Vacuum and Modified Atmosphere Packaging","authors":"M. Karim, Masudur Rahman, E. J. Alice, M. Amanullah, Md Akhtar Hossain, M. Islam","doi":"10.15578/squalen.v15i3.483","DOIUrl":"https://doi.org/10.15578/squalen.v15i3.483","url":null,"abstract":"In order to develop a proper packaging system for sliced tilapia fish (Oreochromis niloticus), the biochemical and microbiological qualities under control (unsealed package), vacuum package and modified atmosphere packaging with 50% CO2/50% N2 (MAP-1) and 50% CO2/50% O2 (MAP-2) were evaluated every three days during 18 days of chilled storage (4±1°C). The pH value was not significantly different (p > 0.05) by treatments until day 9, but significantly lower values (p < 0.05) were observed on day 12 of the storage in all treated samples compared to the control. The total volatile base nitrogen (TVB-N) value progressively increased, but not significantly different (p > 0.05) in all treatments during the entire storage period. The thiobarbituric acid reactive substances (TBARS) amounts were significantly lower (p < 0.05) on day 12 in the vacuum and MAP-1 samples compared to the control sample, and were significantly higher (p < 0.05) on day 6, 9, and 12 of the storage period in MAP-2 samples compared to the control, vacuum and MAP-1 samples. The amounts of pH, TVB-N, and TBARS in all samples did not exceed the acceptable limit in almost the entire storage. The total viable count (TVC) progressively increased with storage time. Nevertheless, TVC values were lower (p < 0.05) on day 6, 9, and 12 of the storage periods in all treatments compared to the control. The TVCs exceeded the acceptable limit (7 log CFU/g) on days 6-9 for control, 9-12 for vacuum, day 12 for MAP-2, and 15 for MAP-1 sample during the storage period. Therefore, the MAP has shown promising results for shelf life extension that can be practiced to display the fishery products with prolonged shelf life. ","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-12-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81480488","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Sedjati, A. Ambariyanto, A. Trianto, E. Supriyantini, A. Ridlo, M. Bahry, Gita Wismayanti, O. Radjasa, Erin P. McCauley
{"title":"Antibacterial Activities of the Extracts of Sponge-Associated Fungus Trichoderma longibrachiatum against Pathogenic Bacteria","authors":"S. Sedjati, A. Ambariyanto, A. Trianto, E. Supriyantini, A. Ridlo, M. Bahry, Gita Wismayanti, O. Radjasa, Erin P. McCauley","doi":"10.15578/squalen.v15i2.438","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.438","url":null,"abstract":"This study aims to explore the antibacterial potential of a sponge-associated fungus Trichoderma longibrachiatum isolated from Ternate waters, North Maluku, Eastern Indonesia. Various culture media were used to stimulate the production of secondary metabolites in T. longibrachiatum. The isolate was cultured in various media for 6-9 days. Then, the antibacterial activities of the ethyl acetate extracts were assayed against pathogenic bacteria of Multi-Drug Resistant (MDR) strain (Pseudomonas aeruginosa, Staphylococcus aureus, Klebsiella pneumoniae, and Bacillus cereus). The results showed that all extracts had similar profiles on the thin layer chromatography. However, two of the most potent extracts were produced from the PCA and MEA media for 9 days. These extracts inhibited methicillin-resistant S. aureus (MRSA) (12.48 mm and 12.27 mm); B. cereus (12.11 mm and 12.12 mm); K. pneumoniae (12.40 mm and 10.76 mm); and P. aeruginosa (11.59 mm and 8.69 mm) at concentrations 500 mg/disc. In conclusion, the fungus T. longibrachiatum that was cultured in PCA and MEA media had the potential to produce antibacterial compounds against MDR pathogens and both had similar compounds. Meanwhile, the ethyl acetate extracts from fungus cultured in the TPA and TA media were inactive against all tested bacteria","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80894068","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Ariyani, E. Kristiningrum, G. Barokah, H. Januar
{"title":"The Effects of Carbon Monoxide Treatment on the Physical and Chemical Qualities of Tuna Steak during Iced Storage","authors":"F. Ariyani, E. Kristiningrum, G. Barokah, H. Januar","doi":"10.15578/squalen.v15i2.456","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.456","url":null,"abstract":"Injection or modification of the atmosphere in the meat packaging by carbon monoxide (CO) has been known to retain the color stability of red meat including those of tuna. The red color in tuna meat has been commonly used as a freshness indicator by consumers, especially those for raw consumption. However, other information on the freshness level in fish, in addition to color, is also important to assess in the food safety of marine and fisheries products. This study aims to evaluate the effects of CO on the chemical and physical properties of tuna steak during storage on ice. This study was conducted using bigeye tuna (Thunnus obesus) as the raw material. The tuna was cut into loins to form steaks and divided into two groups, one group without CO injection or control, and another group was injected with CO. Both CO-treated tuna steak and control were preserved in a cool-box filled with ice for 14 days. The observation was conducted every two days by determining color (chromameter method), sensory preference (hedonic method), and several chemical parameters, including total volatile base (TVB), K value, and histamine content that related to the spoilage process. Results showed that after 14 days of preservation in iced storage, the reddish color of CO-treated tuna steak was retained, whereas that of control turned brown. In the sensory tests, the panelists preferred the CO-treated tuna steak to control due to its reddish color. There were no significant differences between the content of TVB accumulation and the K value in CO-treated tuna steak and the control. Furthermore, the K value of CO-treated tuna steak and control reached the rejected level on day 14. The difference between CO-treated tuna steak and control was based on the content of histamine, where that of control was significantly higher than tuna steak treated with CO. Therefore, this research showed that the effects of CO treatment were only on the appearance of the steak; meanwhile, the deterioration process in fish is generally unaffected. Precautions are thus needed for consumers, since color may not be the only factor that indicates the freshness of tuna steak.","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89291195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rapid and Simultaneous Detection of Vibrio parahaemolyticus, Salmonella spp. and Escherichia coli in Fish by Multiplex PCR","authors":"R. Triwibowo, Novalia Rachmawati, D. Dwiyitno","doi":"10.15578/squalen.v15i2.444","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.444","url":null,"abstract":"Pathogenic bacteria are commonly found as natural contaminants in seafood and fish products. Globally, several countries have been imposing strict regulations on the maximum levels of pathogens and consequently require microbial testing of pathogens before the products can be marketed. A culture-based method with biochemical assay has been widely used to detect pathogenic bacteria in food, despite its long and extensive process. Meanwhile, the alternative molecular-based method to overcome this problem, cannot differentiate between viable and nonviable cells, which may lead to underestimation. This study aimed to develop a multiplex PCR (mPCR) method as a confirmatory assay for the culture-based method to detect pathogens in fish products simultaneously. This method applied a pre-enrichment step to ensure the growth of low-level pathogens and the injured cells in the sample. The target genes were ToxR, InvA, and UidA for Vibrio parahaemolyticus, Salmonella spp. and Escherichia coli, respectively. This assay also amplified the 16S rDNA gene of bacteria as an internal control for the PCR reaction. By implementing liquid-based DNA extraction during analysis, the developed-mPCR was comparable to detect the targeted bacteria in artificially-contaminated samples. The method was more sensitive in naturally-contaminated samples, where the number of E. coli, Salmonella spp. and V. parahaemolyticus detected were 28, 7, and 22, respectively. While the conventional method only detected 26, 5, and 19 of the respective pathogens. With a relatively shorter time and lower operation cost, the mPCR method is potential as an alternative for the culture-based method.","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91292238","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pustika Ratnawati, N. F. Simatupang, P. R. Pong-Masak, N. Paul, G. Zuccarello
{"title":"Genetic Diversity Analysis of Cultivated Kappaphycus in Indonesian Seaweed Farms using COI Gene","authors":"Pustika Ratnawati, N. F. Simatupang, P. R. Pong-Masak, N. Paul, G. Zuccarello","doi":"10.15578/squalen.v15i2.466","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.466","url":null,"abstract":"Indonesia is a major player in the aquaculture of red algae, especially carrageenan producing ‘eucheumatoids’ such as Kappaphycus and Eucheuma. However, many current trade names do not reflect the evolutionary species and updated taxonomy, this is especially the case for eucheumatoid seaweeds that are highly variable in morphology and pigmentation. Genetic variation is also not known for the cultivated eucheumatoids in Indonesia. Therefore, this study aimed to determine the species and the level of genetic variation within species of cultivated eucheumatoids from various farms across Indonesia, spanning 150-1500 km, using the DNA barcoding method. Samples of seaweed were randomly collected at 14 farmed locations between April 2017 and May 2018. For this study the 5-prime end (~ 600 bp) of the mitochondrial-encoded cytochrome oxidase subunit one (COI) was amplified and sequenced. Morphological examination showed that the samples were quite variable in branching pattern and color. All samples collected from farms with floating line cultivation were identified based on COI sequences as Kappaphycus alvarezii and showed no variation in the COI gene. One farm sample with bottom-line cultivation was identified as K. striatus. The low genetic variation is in contrast to the phenotypic variation of samples, indicating that variation and phenotypic responses to environments is still found in samples with implications for growth rates and carrageenan yield and quality. Information about the genetic variation in stocks is important base knowledge for maintaining, expanding and continuing seaweed aquaculture.","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72823856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Front Cover Squalen Bulletin Vol. 15 No. 2 Tahun 2020","authors":"Squalen Buletin","doi":"10.15578/squalen.v15i2.491","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.491","url":null,"abstract":"","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78962738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Back Cover Squalen Bulletin Vol. 15 No. 2 Tahun 2020","authors":"Squalen Buletin","doi":"10.15578/squalen.v15i2.494","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.494","url":null,"abstract":"","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85024270","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Preface Squalen Bulletin Vol. 15 No. 2 Tahun 2020","authors":"Squalen Buletin","doi":"10.15578/squalen.v15i2.495","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.495","url":null,"abstract":"","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75557094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Ethica, Nurlaila Hidayati, H. Fuad, C. Arham, R. Ariyadi, E. Purwaningrum, K. Z. Rahman
{"title":"Detection of rtxA Gene as a Biomarker of Seafood-Borne Pathogen Vibrio cholerae using In Silico PCR Assay","authors":"S. Ethica, Nurlaila Hidayati, H. Fuad, C. Arham, R. Ariyadi, E. Purwaningrum, K. Z. Rahman","doi":"10.15578/squalen.v15i2.417","DOIUrl":"https://doi.org/10.15578/squalen.v15i2.417","url":null,"abstract":"Seafood-borne outbreaks caused by Vibrio cholerae have led to the increased need for food safety risk assessment of marine products. An in silico investigation about the potential of virulence gene of V. cholerae, rtxA, as a DNA biomarker of the toxigenic bacterium has been carried out. The aim of this study was to use the bacterial DNA biomarker sequence as a tool to facilitate early rapid detection of cholera infection. Five specific pairs of primers were designed from the rtxA open reading frame DNA of V. cholerae O1 biovar El Tor str. N16961 genomic DNA using Primer3Plus. Next, in silico Polymerase Chain Reaction (PCR) assay was carried out using the newly designed primers and 25 genomic DNA of vibrio spp. retrieved from the in silico database. One of the five designed pairs of primers, RtxAOF-RtxAOR: ‘5-CGCAAAACAGTTTCAGCCGA-3’ and 5’-AGGTTGGTCTTTTGTGGCCA-3’, could result in single DNA amplicon sized 518 bp only from V. cholerae species. No amplicon bands were produced from 17 other vibrio genomes studied using similar RtxAF-RtxAR primers. A further check showed that the amplicon was indeed part of the rtxA gene of V. cholerae. Based on this in silico study, rtxA gene appeared to be a DNA biomarker of V. cholerae, which is potential to facilitate rapid diagnosis of the virulence bacterium using in silico PCR assay.","PeriodicalId":21935,"journal":{"name":"Squalen Bulletin of Marine and Fisheries Postharvest and Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73935434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}