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The physical profile and chemical composition of growing media are vital in evaluating fish waste filtration efficiency and plant growth performance in aquaponics. The present study reported and compared the physical and chemical evaluation of the novel fabricated Kaolina, gravel, and commercially used lightweight expanded clay aggregate (LECA) as growing medias in aquaponics. Field emission scanning electron microscopy with energy-dispersive X-ray spectroscopy (FESEM-EDX) was utilized to analyze the growing media's chemical composition and structural characterization. The resultant effect of these growing medias on water quality and the growth performance of Clarias gariepinus and Lactuca sativa were also reported. Kaolina exhibited an excellent physical profile (42.95 ± 1.39%) in water absorption capacity as compared to LECA (35.90 ± 1.28%) and gravel (1.97 ± 0.25%), showing a significant difference at p < 0.05. The addition of 25% w/w Musa paradisiaca peel in the fabrication of Kaolina gives an added value of 88.0% of K and 100% of P elements, which show a significant difference (p < 0.05) compared to LECA. The results obtained reveal a better daily growth rate (DGR) and relative growth rate (RGR) of L. sativa at 0.57 ± 0.02 cm day−1 and 0.21 ± 0.00 g day−1, respectively. Results indicated that the porous structure of growing media could contribute to the high-water retention capability and slow the water desorption process. Hence, it could increase the ability of the growing media to hold nutrients for plant intake, resulting in higher removal percentage of nutrients in aquaponics system. Kaolina gives the highest nutrient removal percentage of TAN (96.86 ± 1.50%), NO 2 − (83.56 ± 1.27%), NO 3 −(77.55 ± 0.48%), and PO 4 3− (79.46 ± 0.42%). The results also shown growing media has considerable impacts on nutrient removal, which contribute to the aquaponic productions. [Display omitted] • Nutrient supplies through Kaolina are more natural and sustainable. • Kaolina eliminate chemical nutrient supply practiced in aquaponics. • Water absorption and retention capacity of Kaolina is more stable. • Kaolina provided essential micronutrients and optimized physical characteristics. • Significant yield of L. sativa and C. gariepinus in Kaolina than LECA and gravel. [ABSTRACT FROM AUTHOR]

Moringa oleifera is characterized by high coagulation properties, low cost and low toxicity hence is very promising to be utilized as an alternative coagulant to recover microalgae biomass from its suspension system. Hence, this study was performed with the objective to investigate the potentiality of M . oleifera as coagulant agent in harvesting microalgae and to investigate the effect of zeta potential in its coagulation-flocculation activity. Bradford protein assay was applied for rapid and accurate determination of protein concentration in the M . oleifera seed powder and protein powder. The flocculation activities were determined at isoelectric pH by computing the flocculation efficiency in terms of microalgae biomass recovery and removal percentage at various coagulant dosages. It was observed that the protein concentration was 211.71 μg g −1 mL −1 in M . oleifera seed powder and 188.16 μg g −1 mL −1 in protein powder which yielded 97% and 78% of biomass recovery, respectively at the dosage of 10 mg L −1 . Result showed that M . oleifera seed derivatives supersede chemical coagulant, alum which yielded 34% of biomass recovery at the same dosage. M . oleifera seed powder and protein powder was proven to be highly promising bio-coagulant and suitable alternative to the chemical coagulant in environmentally-sustainable harvesting of microalgae biomass. [ABSTRACT FROM AUTHOR]

Current microalgae harvesting technology depends on sophisticated and complex approaches such as hollow fiber filtration, chemical flocculants and centrifugation, which are deemed feasible if high value products were obtained. In this study the potential of auto-flocculating microalgae Ankistrodesmus sp. was examined for its potential as bio-flocculant to harvest Chlorella sp. Zeta Potential Analysis was performed on the microalgae in the pH range of 4.16–9.55 before subjecting the microalgae to the coagulation – flocculation assay. The isoelectric point of microalgae suspension was observed in the range of pH 5–8 and the magnitude of zeta potentials ranged between −10 mv to −35 mV. Ankistrodesmus sp. was inoculated at a dosage of 50% (v/v) into a batch of Chlorella sp. culture during the coagulation – flocculation assay. The removal efficiency shown by Ankistrodesmus sp. was 82% at pH 7.1 followed by 55% at pH 6.2. Utilizing Ankistrodesmus sp. for flocculation was efficient since it did not require any changes of pH because isoelectric point was observed within the normal pH of Chlorella sp. growth condition. Development of innovative microalgae treatment technology incorporating continuous bio-harvesting with microalgae-microalgae flocculation could provide a low-cost and sustainable wastewater treatment approach. In addition, the use of microalgae itself to harvest microalgae biomass harvesting could simplify downstream processing, saving resources and would reduce the production cost for future microalgae-based technology. [ABSTRACT FROM AUTHOR]

This study investigated the temporal variations of water quality parameters and ecotoxic trace metal contamination in the Opuroama River over a year, with a focus on providing baseline data for regulating water and fisheries resources in the area. Metal concentrations in sediment, water, and four aquatic organisms were analyzed for cadmium (Cd), chromium (Cr), nickel (Ni), and lead (Pb) using atomic absorption spectrophotometry. Metal concentration in C. amnicola occurred in the order: Cr>Cd>Ni>Pb, U. tangeri: Cr>Pb>Cd>Ni, T. fuscatus: Cr>Pb>Ni>Cd, P. monodon: Pb>Cr>Ni>Cd, while in sediment, the order was Cr>Pb>Cd>Ni, and water occurred in the order: Cr>Pb>Ni>Cd. Results showed temporal variations in water physicochemical parameters, with Cd and Ni concentrations within 0.003 mg/L, and 0.02 mg/L reported as set standard limits for aquatic ecosystems except for Cd in December, which exceeded permissible limits. Pb concentrations were below the threshold of 0.01 mg/L from January to May but progressively increased and exceeded limits from June to December. Cd had the highest mean concentration in sediment and the least in water and aquatic organisms, while Ni had the highest mean concentration in U. tangeri and water and the lowest in T. fuscatus and P. monodon. Pb had the highest concentration in water and the lowest in C. amnicola, while U. tangeri had the highest mean Cr value. The study suggests potential health risks to humans and the environment from the presence of potentially toxic elements in the studied media. [ABSTRACT FROM AUTHOR]

The aquaponic recirculation system (ARS) combined aquaculture and hydroponic systems in a mutually beneficial environment. In this study, African catfish, Clarias gariepinus with Butterhead lettuce, Lactuca sativa were cultivated to evaluate gravel-based media and lightweight extended clay aggregate (LECA) as a physical filtration in the nutrient's removal. The performance of both tested growing media was assessed through the reduction of nutrient concentrations in the circulated water, which were total ammonia nitrogen (TAN), nitrite-nitrogen (NO 2 --N), nitrate-nitrogen (NO 3 --N), and phosphorus (PO 4 3--P). Statistically, there were significant differences in the percentage of nutrient removal between gravel-based media and LECA treatment for TAN, NO 2 --N, NO 3 --N, and PO 4 3--P. TAN removal efficiency achieved 92.47 ± 1.03% in LECA compared to 61.26 ± 2.69% in gravel-based media. For NO 2 --N, the removal efficiency was 77.25 ± 1.47% and 22.43 ± 6.84% in LECA and gravel-based media. The removal efficiency of NO 3 --N on LECA was two times more than gravel-based, 60.03 ± 1.58% and 30.77 ± 1.54%. The removal efficiency of PO 4 3--P was 64.29 ± 1.82% for LECA while 27.43 ± 1.62% for gravel-based media. In addition, L. sativa yield was significantly higher in LECA with 64,961.71 ± 1295.61 g/m² as compared to 31,0582.82 ± 877.07 g/m² in gravel-based media. Significantly higher SGR of C. gariepinus in LECA with 3.94 ± 0.11%/day compared to 3.10 ± 0.12%/day in gravel-based media. LECA is an adsorptive substrate with a high removal capacity for phosphorus and nitrogen in aquaculture wastewater, increase its use as growing media in ARS or hydroponics. [Display omitted] • Aquaponics combined aquaculture and hydroponic in a beneficial environment. • Growing media accumulate nutrients for aquaponic system sustainability. • Significant yield of L. sativa and C. gariepinus in LECA than gravel media. [ABSTRACT FROM AUTHOR]

Moringa oleifera (MO) seed has been widely used for water treatment purposes due to their good flocculation, low cost and non-toxic characteristics. However, these advantages had not yet been utilized for the microalgae harvesting technology. Until today, the harvesting of microalgae biomass still depend on sophisticated and complex approaches such as hollow fiber filtration, chemical flocculants and Alfa Laval decanter technology. Thus, in this study the potential of natural plant-based coagulant was investigated. MO seed derivatives were determined for the harvesting of suspended freshwater microalgae, Chlorella sp.. Flocculation characteristics with various dosages were optimized. The output of this study proved that primary and tertiary MO derivatives yield excellent flocculation efficiency of more than 95% at 20 min sedimentation. In fact, MO derivatives even supersede chemical flocculants, Aluminum Sulfate in terms of flocculation efficiency and biomass recovery at a low dosage of 10 mg L −1 and normal pH (6.9–7.5). Seed powder had the highest removal efficiency whereas seed protein had the highest biomass recovery. Utilization of M. oleifera derivatives as bio-coagulant provides several advantages such as lower impact on the environment, lower cost for microalgae harvesting, allow rapid microalgae culture expansion and as chemical-free green technology. [ABSTRACT FROM AUTHOR]

Bioremediation of aquaculture wastewater utilizing naturally occurring bacteria and microalgae have been widely used since 1990s in open pond. However, the relationship between both bioremediators especially in term of nutrient reduction had not been studied thoroughly in enclosed treatment system. Bioremediation of either Effective Microorganisms (EM) or microalgae (MA) independently required additional supply of oxygen and carbon dioxide, respectively to sustain their growth and treatment efficiency. Conversely, symbiotic bioremediation could omit these requirement due to the associate relation between both in term of respiration. EM bioremediation would produce CO 2 and consume O 2 whereas microalgae is vice versa. On top of that, both EM and microalgae simultaneously function as degradation of organic matter. In this study, symbiotic MA–EM showed higher removal percentage and removal rate on phosphorus of 99.15% and 0.534 mg L −1 d −1 as compared to 49.73% and 0.130 mg L −1 d −1 for the conventional MA bioremediation. However, inoculation of EM in the symbiotic MA–EM bioremediation did not significantly improved the removal of ammonia. With proper optimization of inoculation volume and bioremediation mode, symbiotic relations of these two microorganisms would benefits in designing more robust, economical and least maintenance on the wastewater treatment system. [ABSTRACT FROM AUTHOR]

Highlights: [•] Growth of microalgae from South China Sea were tested in Conway and f/2 media. [•] Parameters including SGR, density and mother–daughter intercept were investigated. [•] Late mother–daughter intercept showed the high-tolerance on nutrient depletion. [•] Chlorella sp. found to be the most resilient among microalgae genera tested. [•] Cultivation medium selection should be based on the application of the microalgae. [ABSTRACT FROM AUTHOR]

Simple Summary: Coral reefs are vital ecosystems with high biodiversity and ecological services for coastal communities. Climate change is accelerating, with detrimental consequences on coral reefs and related communities, but it is challenging to keep up with the literature given its current rapid expansion. The current review foresees three future trends in the area of coral reefs and climate change, including (i) incorporating future scenarios, (ii) climate-induced temperature changes, and (iii) adaptation strategies, which are expected to move society closer to the following Sustainable Development Goal: 13 Climate Action. In this scientometric review, we employ the Web of Science Core Collection to assess current publications and research trends regarding coral reefs in relation to climate change. Thirty-seven keywords for climate change and seven keywords for coral reefs were used in the analysis of 7743 articles on coral reefs and climate change. The field entered an accelerated uptrend phase in 2016, and it is anticipated that this phase will last for the next 5 to 10 years of research publication and citation. The United States and Australia have produced the greatest number of publications in this field. A cluster (i.e., focused issue) analysis showed that coral bleaching dominated the literature from 2000 to 2010, ocean acidification from 2010 to 2020, and sea-level rise, as well as the central Red Sea (Africa/Asia), in 2021. Three different types of keywords appear in the analysis based on which are the (i) most recent (2021), (ii) most influential (highly cited), and (iii) mostly used (frequently used keywords in the article) in the field. The Great Barrier Reef, which is found in the waters of Australia, is thought to be the subject of current coral reef and climate change research. Interestingly, climate-induced temperature changes in "ocean warming" and "sea surface temperature" are the most recent significant and dominant keywords in the coral reef and climate change area. [ABSTRACT FROM AUTHOR]

Mass cultivation of high-value aromatic herbs such as Vietnamese coriander and Persicaria odorata required specific soil, nutrients, and irrigation, mostly found in the limited natural wetland. This study aimed to evaluate the capacity of P. odorata at different densities in nutrient removal and the growth performance of African catfish, Clarias gariepinus in aquaponic systems. P. odorata was cultivated for 40 d with less than 10% water exchange. The effects of increasing crop densities, from zero plants for the control, 0.035 ± 0.003 kg/m2 in Treatment 1, 0.029 ± 0.002 kg/m2 in Treatment 2, and 0.021 ± 0.003 kg/m2 in Treatment 3, were tested on the growth performance of C. gariepinus with an initial density of 3.00 ± 0.50 kg/m3. The specific growth rate (S G R), daily growth rate of fish ( D G R f), and survival rate (S R) of the C. gariepinus were monitored. Nutrient removal, daily growth rate of plant (D G R p) , relative growth rate (R G R), and the sum of leaf number (Ʃ n) of the P. odorata plant were also recorded. It was found that nutrient removal percentage significantly increased with the presence of P. odorata at different densities. The growth performance of C. gariepinus was also affected by P. odorata density in each treatment. However, no significant difference was observed in the D G R p and R G R of the P. odorata (p > 0.05), except for Ʃ n values. Treatment 1 had the highest Ʃ n number compared to Treatment 2 and Treatment 3, showing a significant difference (p < 0.05). This study demonstrates that the presence of P. odorata significantly contributes to lower nutrient concentrations, supporting the fundamental idea that plants improve water quality in aquaponic systems. [Display omitted] • P. odorata needs a large natural wetland area for cultivation. • Aquaponics offers an alternative artificial wetland for cultivation. • Various P. odorata densities were tested to optimize growth performance. • P. odorata in aquaponics grew three times faster than in nature. • Less than 10% water exchange promotes zero-waste. [ABSTRACT FROM AUTHOR]

Seahorses, widely recognized as a unique genus within aquatic species, are exploited globally across traditional medicine, aquarium, and curio industries. Notwithstanding their popularity, there exists a dearth of current bibliometric investigations capable of discerning key shifts and patterns within seahorse research. In addressing this gap, our study deployed scientometric techniques on the Web of Science database, enabling an encompassing and contemporary bibliometric analysis spanning from 1976 to 2022. Utilizing CiteSpace software, we generated visual data of dual map overlay, citation networks of authors, countries, and documents, and discerned key terms and research clusters prevalent in seahorse-related research. This process yielded 1840 original articles on seahorse research, forming a 13-cluster network, with the three most expansive research clusters being "endangered seahorse", "habitat association", and "male pregnancy". Our investigation highlighted that the terms "gene expression", "abdominal", and "embryonic development" were predominantly employed across seahorse-centric scholarly works. The research ecosystem encompassing seahorses constitutes a diverse array of academic domains, showcasing substantial interdisciplinary linkages among areas such as "Marine and Freshwater Biology", "Environmental Sciences", "Biochemistry and Molecular Biology", "Biodiversity Conservation", "Ecology", "Fisheries", "Zoology", and "Oceanography". The implications of our findings not only establish a robust foundation for subsequent research but also illustrate the evolved state and potential impact of seahorse research within the sphere of marine biology. [ABSTRACT FROM AUTHOR]

Microbes, or microorganisms, have been the foundation of the biosphere for over 3 billion years and have played an essential role in shaping our planet. The available knowledge on the topic of microbes associated with climate change has the potential to reshape upcoming research trends globally. As climate change impacts the ocean or marine ecosystem, the responses of these "unseen life" will heavily influence the achievement of a sustainable evolutionary environment. The present study aims to identify microbial-related research under changing climate within the marine environment through the mapping of visualized graphs of the available literature. We used scientometric methods to retrieve documents from the Web of Science platform in the Core Collection (WOSCC) database, analyzing a total of 2767 documents based on scientometric indicators. Our findings show that this research area is growing exponentially, with the most influential keywords being "microbial diversity," "bacteria," and "ocean acidification," and the most cited being "microorganism" and "diversity." The identification of influential clusters in the field of marine science provides insight into the hot spots and frontiers of research in this area. Prominent clusters include "coral microbiome," "hypoxic zone," "novel Thermoplasmatota clade," "marine dinoflagellate bloom," and "human health." Analyzing emerging trends and transformative changes in this field can inform the creation of special issues or research topics in selected journals, thus increasing visibility and engagement among the scientific community. • A comprehensive scientometric analysis has been conducted to evaluate the quantitative relationship between microbial communities, climate change, and the marine ecosystem. This assessment employs advanced statistical techniques to analyze the existing body of literature and identify significant patterns and trends. • The anticipated key research focus in the near future is the "coral microbiome," with "human health" being a close second. This projection emphasizes the growing importance of understanding the role of microorganisms in coral reef ecosystems and their potential implications for human well-being. • Among the most impactful keywords identified within the subject matter are "microbial diversity" and "ocean acidification." These terms highlight the critical need for continued investigation into the complex interplay between marine microbial communities and the effects of climate-induced oceanic changes, such as increased acidity levels. • The study also underscores the importance of robust international collaboration in advancing our understanding of this interdisciplinary field. [ABSTRACT FROM AUTHOR]

Simple Summary: Here, we strive to summarize the current literature on crayfish research. Using scientometric analysis, we identified the top contributing researchers, the top-cited research articles, the most popular journals, top areas in the field, most influential articles and most keywords used, etc. The most common themes among these top research articles were related to invasive crayfish species as well as the neurochemistry of crayfish. A scientometric analysis was conducted to investigate the trends and development of crayfish research in terms of literature published, author, affiliation, and countries' collaborative networks, as well as the co-citation dataset (e.g., author, article, and keywords). The study analyzed 12,039 bibliographic datasets from the Web of Science, using CiteSpace as a tool for the co-citation analysis. The study revealed extraordinary increases in publication trends, with a total of 21,329 authors involved in approximately 80% of countries around the world (163/195) having conducted crayfish research. Unsurprisingly, countries such as the USA and China, followed by European countries, were among the top countries that have published crayfish-related studies. The findings also indicated that "invasive crayfish" was the world's top keyword for crayfish research. Crayfish species are important for both environmental sustainability (invasiveness and species composition) and social wellbeing (aquaculture), which provides directions for research, philanthropic, academic, government, and non-government organizations regarding how to invest limited resources into policies, programs, and research towards the future management of this species. Our study concluded that strategic collaboration among authors, institutions, and countries would be vital to tackle the issue of invasive crayfish species around the world. [ABSTRACT FROM AUTHOR]

Reproductive health and male fertility are closely related to dietary practices. In recent years, Malaysia has shown a lot of interest in using herbal plants as dietary supplements or in the treatment of numerous diseases. Aquilaria malaccensis, commonly known as karas or gaharu, has recently gained attention for its potential to cure many diseases due to its pharmacological properties. However, studies on its effect on male fertility and reproductive organs are very scarce. This study was conducted to determine the effect of A. malaccensis on male reproductive organs' weight (testis, epididymis, prostate gland and seminal vesicle) and sperm quality (sperm count, sperm morphology and sperm motility) in adult Sprague Dawley rats. Twenty-four male Sprague Dawley rats were allocated into four treatment groups; Control (C: 1 mL of distilled water, n = 6), Treatment 1 (T1: 1 g A. malaccensis/kg body weight, n = 6), Treatment 2 (T2: 2 g A. malaccensis/kg body weight, n = 6) and Treatment 3 (T3: 3 g A. malaccensis/kg body weight, n = 6), respectively. Distilled water and A. malaccensis were administered by oral gavage once daily for 28 days. The rats were euthanised on Day 29 for assessment of reproductive organs' weight and sperm quality. Result shows that weight of testis, epididymis, prostate gland, seminal vesicle and sperm motility did not differ (p > 0.05) among control and treated groups. A significant increase (p < 0.05) of sperm number (1.36 × 10-6) and a decrease (p < 0.05) in percentage of the abnormal sperm (8.17%) were observed in T1 group when compared to Control group. Incremental dosage of A. malaccensis seemed to decrease number of sperm (T3: 0.78 × 10-6 < T1: 1.36 × 10-6 with p < 0.05) and increase percentage of abnormal sperm (T3: 18.83% > T2: 12.17% > T1: 8.17% with p < 0.05). In conclusion, the administration of either 1, 2 or 3 grams of A. malaccensis did not alter the reproductive organs' weight and sperm motility. However, the higher concentration of A. malaccensis consumed by the rats seemed to have detrimental effects on the number and morphology of sperm. [ABSTRACT FROM AUTHOR]

Textile industry has been rapidly progressing over the years, leading to an increasing volume of water usage that contributes to the large production of textile wastewater. Biological treatment processes have been proven to be the most environmentally friendly, cost-effective and requiring reduced production treatment by-products. In this study, using microbial treatment was applied. Three potential local isolates of micro-organism had been isolated from textile wastewater. The treatment processes were studied under two conditions, namely aerobic and anaerobic. Decolourization of seven commercial textile dyes, namely Crystal Violet 3, Acid Black 1, Basic Blue 8, Acid Blue 147, Congo R, Chrysoiodine R and Yellow 2 G were studied. After seven days of incubation, a significant reduction of 92% for Yellow 2G (Y) and 73.73%for Chrysoiodine R was observed, indicating a high capability of the bacterial isolates indye-degrading activities. Highest chemical oxygen demand (COD) removal was achieved byisolate C3K (93.93%), followed by isolate C3W (90.5%) and isolate C1 (89.173%) in nineincubation days, highlighting the ability of these microbial isolates in removing COD from the individual textile dyes. [ABSTRACT FROM AUTHOR]

This study focuses on the evaluation of the performance of Chlorella sp. in removing nutrient in aquaculture wastewater and its correlation with the kinetic growth of Chlorella sp. The treatment was applied with various Chlorella sp. inoculation dosage ranging from 0% to 60% (v/v) of wastewater. The optimum inoculation dosage was recorded at 30% (v/v) with effluent concentration of ammonia and orthophosphate recording at 0.012 mg L −1 and 0.647 mg L −1 , respectively on Day 11. The optimum dosage for bio-flocculation process was obtained at 30 mg L −1 of Aspergillus niger with a harvesting efficiency of 97%. This type of development of phytoremediation with continuous bio-harvesting could promote the use of sustainable green technology for effective wastewater treatment. [ABSTRACT FROM AUTHOR]

Development of aquaculture industry is restricted due the undesirable environmental impact associated with the effluent discharge that is rich in inorganic nitrogenous compound and organic matters. This situation could be improved through the implementation of Bioflocs Technology (BFT). BFT can enhance the water quality in aquaculture system by introducing natural nutrient recycling characteristics with the induction of appropriate carbon/nitrogen (C/N) ratio. However, the natural condition of aquaculture system, which is rich in inorganic nitrogen, could not sustain BFT. Thus, additional carbon is required to obtain a suitable C/N ratio for effective formation of bioflocs complex. This study focused on the determination of optimum C/N ratio by varying the dosage of carbon introduced into the system. Five different C/N ratios (i.e. 10, 15, 20, 25, 30) were evaluated in treating the aquaculture system culturing Clarias gariepinus to an acceptable water quality. Bioflocs density and water quality parameters were monitored throughout the treatment period. The highest removal of ammonia was achieved at 98.7% with the formation of 92.5 mL L −1 of bioflocs concentration at an optimum C/N ratio of 15. The results show that the utilization of BFT can potentially provide a sustainable and low maintenance treatment of aquaculture system. [ABSTRACT FROM AUTHOR]

Seaweed has garnered increasing interest due to its capacity to mitigate climate change by curbing carbon emissions from agriculture, as well as its potential to serve as a supplement or alternative for dietary, livestock feed, or fuel source production. Moreover, seaweed is regarded as one of the earliest plant forms to have evolved on Earth. Owing to the extensive body of literature available and the uncertainty surrounding the future trajectory of seaweed research under evolving climate conditions, this review scrutinizes the structure, dynamics, and progression of the literature pertaining to seaweed and climate change. This analysis is grounded in the Web of Science Core Collection database, augmented by CiteSpace software. Furthermore, we discuss the productivity and influence of individual researchers, research organizations, countries, and scientific journals. To date, there have been 8047 articles published globally (after a series of filters and exclusions), with a notable upswing in publication frequency since 2018. The USA, China, and Australia are among the leading countries contributing to this research area. Our findings reveal that current research on seaweed and climate change encompasses 13 distinct research clusters, including "marine heatwave", "temperate estuary", "ocean acidification", and "macroalgal bloom". The most frequently cited keywords are "climate change", "biomass", "community", and "photosynthesis". The seaweed species most commonly referenced in relation to climate change include Gracilaria sp., Sargassum sp., Ecklonia maxima , and Macrocystis pyrifera. These results provide valuable guidance for shaping the direction of specialized topics concerning marine biodiversity under shifting climate conditions. We propose that seaweed production may be compromised during prolonged episodes of reduced water availability, emphasizing the need to formulate strategies to guarantee its continued viability. This article offers fresh perspectives on the analysis of seaweed research in the context of impending climate change. • Linking a global trends of seaweed and climate change literature. • Five countries with 60% of publications, USA, Australia, China, France, Spain. • Collaboration networks actively occurred in the last five years. • Keywords analysis revealed "Growth", "macroalgae" and climate change" are previous focus study. • Four keywords - "blue carbon", "tolerance", "yield" and "marine heatwave" are recently receiving strongest attention. [ABSTRACT FROM AUTHOR]

The application of solid acid catalyst in biodiesel production eliminates the tedious pretreatment of feedstock and eradicates generation of high volume of wastewater. A novel acid catalyst was prepared via sulfonation of incompletely carbonized coconut shell using concentrated sulfuric acid. The design of experiments were performed using four factor-three-level central composite design coupled with response surface methodology to evaluate the interaction between two factors in order to determine the optimum process conditions. A quadratic model was suggested for the prediction of biodiesel yield. The F-value and p-value of the model were 4.02 and 0.0129, respectively, indicate that the model was statistically significant at 95 per cent confidence interval. In addition, R 2 value of the model was 0.8364, which indicates the acceptable accuracy of the model. From the optimization study, it was found that the carbonization temperature, carbonization time, sulfonation temperature and sulfonation time were 422 °C, 4 h, 100 °C and 15 h, respectively. At these optimum conditions the predicted and observed biodiesel yield were 88.15 per cent and 88.03 per cent, respectively, which experimentally verified the accuracy of the model. The use of coconut shell-derived solid acid catalyst in biodiesel production promotes the sustainable and green way of operations. [ABSTRACT FROM AUTHOR]

Crabs categorized as cold-blooded organisms are especially at risk as climate change worsens. Their current situation was not well documented, especially in terms of scientometric analysis. The present study aims to investigate the relationship between research on crabs and climate change-related studies, with a focus on identifying trends and hotspots over time. The analysis was based on a collection of over 2834 relevant documents and 107,502 cited references indexed in the Web of Science Core Collection (WOSCC) database from 1977 to 2022. The findings indicated an increase in research in recent decades, with the USA as the largest contributor, followed by China and Brazil. Researchers from the USA and Germany were among the top published authors in the field. The most highly cited studies in WOSCC focused on the relationship between harmful algal blooms and crab research. Of these studies, 20 clusters were generated, with the most influential cluster identified as related to "ocean acidification," "blue king crab," and "mud crab fishery." The most frequently cited and influential keywords in the field were "climate change" and "hypoxia," respectively. Our conclusion is that the fields of "research on crabs" and "climate change" are thriving and that further exploration of the adaptation strategies of these organisms is necessary. This knowledge will benefit scientific communities, philanthropic funders or related governments, fisheries-related industries, and NGOs towards the sustainable management of commercial crab species in the future. • Analyzed 2834 articles and 107,502 cited references from the (WOSCC) database, spanning 1977 to 2022. • Identified leading contributors, institutions, research hotspots, and frontiers in the field. • Categorized pivotal research issues and delineated the knowledge structure pertaining to marine biodiversity. • Explored emergent research frontiers and hotspots in marine biodiversity studies. • Assessed the current state of research and pinpointed prospective future avenues for investigation in this domain. [ABSTRACT FROM AUTHOR]

Shrimp is an important traded fishery commodity. When subjected to stress, shrimp usually suffers from oxidative stress, which leads to cell injury, senescence, and death. To maintain shrimp good health, performance and production, antioxidant and immune systems are important. Natural antioxidants found in microalgae may be used to increase the cell protection against oxidative damage, being a promising alternative to the carcinogenic synthetic antioxidants. In this study, Tetraselmis chuii was evaluated for its effect on survival, growth and oxidative stress biomarkers on Litopenaeus vannamei postlarvae (PL). The antioxidant properties of the formulated feed with T. chuii inclusion were determined using four antioxidant chemical assays. Meanwhile, the oxidative stress biomarkers on PL were analyzed by hydrogen peroxide, membrane stability and lipid peroxidation assays. Results showed that PL reared on diets supplemented with 50% T. chuii had a significantly higher ( P ≤ 0.05) survival (97.6 ± 1.4%) and lower oxidative stress in terms of hydrogen peroxide content (10.08 ± 0.4 mM g FW) and electrolyte leakage (10.8 ± 0.3%). The result of this study also showed that shrimp PL reared on diets supplemented with microalgal, T. chuii have high resistance to reverse salinity stress test (76.7-100%). However, no significant differences ( P ≥ 0.05) were found in the growth and lipid peroxidation. Due to the positive effect on oxidative stress status, survival and resistance to salinity stress, the feeding of L. vannamei PL with diet containing at least 50% of T. chuii is recommended as a natural source of antioxidant for PL. [ABSTRACT FROM AUTHOR]

• B.enclensis was identified as bioflocculant-producing bacteria based on morphological and flocculating activity. • Bioflocculant-producing bacteria, B. enclensis yielded 93% of flocculation efficiency. • Microplastics was incubated with B. enclensis , changes in physical and chemical properties were observed by SEM and FTIR. • The microplastics served as the sole source of carbon for the bacterial culture that was grown in Mineral Salt Medium. • Inoculation of B. enclensis with microplastics provide eco-friendly treatment for microplastic pollution in aquaculture. [ABSTRACT FROM AUTHOR]

Nannochloropsis sp. and Tetraselmis sp. are widely used in aquaculture as a source of protein, lipid and carbohydrate. The growth and proximate composition of microalgae could be affected by different culture conditions especially salinity, temperature and light. Thus, this study was aimed to compare the growth and proximate composition of Nannochloropsis sp. and Tetraselmis sp. cultured in different salinities and pH under different culture conditions. In this study Nannochloropsis sp. and Tetraselmis sp. were isolated from South China Sea and cultured at different salinities of 20, 30 and 40 ppt and different pH of 5.5, 7.5, 8.5 and 9.5 under natural and control condition until stationary phase. Results showed that Nannochloropsis sp. and Tetraselmis sp. had significantly higher ( p < 0.05) cell density, lipid and carbohydrate content under control condition at 30 ppt. However, protein content was significantly higher ( p < 0.05) in Nannochloropsis sp. when cultured under natural condition at 30 ppt. High cell density, protein, lipid and carbohydrate content was obtained when cultured at pH 7.5 and 8.5 for both species. The output of this study could be considered for Nannochloropsis sp. and Tetraselmis sp. cultivation to provide appropriate levels of protein, lipid and carbohydrate as feed supplement for aquaculture organisms. [ABSTRACT FROM AUTHOR]