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Phycoerythrin (PE) is a pink/red-colored pigment found in rhodophytes, cryptophytes, and blue-green algae (cyanobacteria). The interest in PE is emerging from its role in delivering health benefits. Unfortunately, the current cyanobacterial-PE (C-PE) knowledge is still in the infant stage. It is essential to acquire a more comprehensive understanding of C-PE. This study aimed to review the C-PE structure, up and downstream processes of C-PE, application of C-PE, and strategies to enhance its stability and market value. In addition, this study also presented a strengths, weaknesses, opportunities, and threats (SWOT) analysis on C-PE. Cyanobacteria appeared to be the more promising PE producers compared to rhodophytes, cryptophytes, and macroalgae. Green/blue light is preferred to accumulate higher PE content in cyanobacteria. Currently, the prominent C-PE extraction method is repeated freezing–thawing. A combination of precipitation and chromatography approaches is proposed to obtain greater purity of C-PE. C-PE has been widely exploited in various fields, such as nutraceuticals, pharmaceuticals, therapeutics, cosmetics, biotechnology, food, and feed, owing to its bioactivities and fluorescent properties. This review provides insight into the state-of-art nature of C-PE and advances a step further in commercializing this prospective pigment.

The relationship between humans and plastics has become intricate due to their versatile nature and low production cost. Plastics generation has surpassed that of other manufactured products, which, coupled with the prevailing poor waste management systems, makes it a serious problem for the terrestrial and aquatic environments as its final destination. Their extensive presence has continued to pose a significant threat, not only to the aquatic ecosystem but also to the approximately 3 billion people relying on it for their livelihood. Even more disturbing were the recent findings of these plastics in food and drinking water and the evidence of human exposure, the long-term health effects of which are largely unknown. This ubiquitous phenomenon has over time put plastics under critical observation, leading to the development of many local and international policies, resolutions, and directives aimed at addressing and reversing the menace. This review provided the first snapshot of the global and local governance strategies currently aimed at mitigating plastic pollution, their limitations, and future directions. The findings of the review revealed several aspects of microplastics (MPs) pollution to be overlooked in policy formulation, a laxity in policy implementation, and an apparent lack of indices to ascertain the impact of the regulations. Furthermore, there is currently no regulation on MPs contamination of food and drinking water and an apparent lack of funding for research into the health effects of plastics and their alternatives. This, therefore, necessitates the need for a well-coordinated approach at international and national levels to scale up these policies in all countries and translate them from paper to measurable, holistic, and realizable actions that will address all forms of plastic pollution.

Fucoxanthin is one of the light-harvesting pigments in brown microalgae, which is increasingly gaining attention due to its numerous health-promoting properties. Currently, the production of microalgal fucoxanthin is not yet feasible from an economic perspective. However, the cultivation of microalgae at favourable conditions holds great potential to increase the viability of this fucoxanthin source. Hence, this study aimed to review the fucoxanthin production of microalgae under different conditions systematically. A literature search was performed using the Web of Science, Scopus and PubMed databases. A total of 188 articles were downloaded and 28 articles were selected for the current review by two independent authors. Microalgae appeared to be a more reliable fucoxanthin source compared to macroalgae. Overall, a consensus fucoxanthin production condition was obtained and proposed: light intensity ranging from 10 to 100 µmol/m2/s could achieve a higher fucoxanthin content. However, the optimal light condition in producing fucoxanthin is species-specific. The current review serves as an antecedent by offering insights into the fucoxanthin-producing microalgae response to different culture factors via a systematic analysis. With the current findings and recommendations, the feasibility of producing fucoxanthin commercially could be enhanced and possibly achieve practical and sustainable fucoxanthin production.

Some cyanobacteria species have a high capacity for accumulating phycobiliprotein contents in their cells. However, there is a lack of information on screening tropical freshwater cyanobacteria, particularly phycobiliproteins. In addition, it is unclear which characteristics of cyanobacteria (morphological and/or growth) could affect phycobiliprotein contents. This study aimed to screen and characterise Malaysian indigenous freshwater cyanobacteria for the growth, biomass, and pigment contents and determine the major characteristic that contributed to the variation of phycobiliproteins. The surface/volume (S/V) ratio, specific growth rate, biomass productivity, and pigment contents of the isolated cyanobacteria were analysed. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) were applied to distinguish the factor responsible for phycobiliprotein variations in cyanobacteria. For the phycobiliprotein contents, Arthrospira sp., Pseudanabaena sp., and Synechococcus elongatus showed significantly higher (p < 0.05) amounts of cyanobacterial phycocyanin (C-PC), phycoerythrin (C-PE), and allophycocyanin (C-APC), respectively, than other studied cyanobacteria. This study showed no apparent trend of similarity and difference between the unicellular and filamentous cyanobacteria. In addition, carotenoid contents demonstrated a positive correlation with total phycobiliproteins, C-PC and C-APC. Based on the current findings, Arthrospira sp., Pseudanabaena sp. and Synechococcus elongatus might be the promising candidate to be the C-PC, C-PE and C-APC sources, respectively, for commercial production purposes. The selection of optimal cyanobacterial strain is crucial for efficient phycobiliprotein production. This study underlined the potential of freshwater cyanobacteria in producing respective and total phycobiliproteins. Future studies such as the optimization process should be adopted to improve the phycobiliprotein production of these cyanobacteria sig

Recent increased interest in seaweed is motivated by attention generated in their bioactive components that have potential applications in the functional food and nutraceutical industries. In the present study, nutritional composition, metabolite profiles, phytochemical screening and physicochemical properties of freeze-dried brown seaweed, Sargassum polycystum were evaluated. Results showed that the S. polycystum had protein content of 8.65 ± 1.06%, lipid of 3.42 ± 0.01%, carbohydrate of 36.55 ± 1.09% and total dietary fibre content of 2.75 ± 0.58% on dry weight basis. The mineral content of S. polycystum including Na, K, Ca, Mg Fe, Se and Mn were 8876.45 ± 0.47, 1711.05 ± 0.07, 1079.75 ± 0.30, 213.85 ± 0.02, 277.6 ± 0.12, 4.70 ± 0.00 and 4.45 ± 0.00 mg 100/g DW, respectively. Total carotenoid, chlorophyll a and b content in S. polycystum were detected at 45.28 ± 1.77, 141.98 ± 1.18 and 111.29 µg/g respectively. The total amino acid content was 74.90 ± 1.45%. The study revealed various secondary metabolites and major constituents of S. polycystum fibre to include fucose, mannose, galactose, xylose and rhamnose. The metabolites extracted from the seaweeds comprised n-hexadecanoic acid, 1,2-benzenedicarboxylic acid, mono(2-ethylhexyl) ester, benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy- methyl ester, 1-dodecanol, 3,7,11-trimethyl-, which were the most abundant. The physicochemical properties of S. polycystum such as water-holding and swelling capacity were comparable to several commercial fibre-rich products. In conclusion, results of this study indicate that S. polycystum is a potential candidate as functional food sources for human consumption and its cultivation needs to be encouraged.

Seaweeds are known as excellent sources of unique bioactive metabolites. In the present study, proton nuclear magnetic resonance (1H NMR) combined with principal component analysis (PCA) was used to distinguish the metabolic variations in Brown seaweed, Sargassum polycystum treated under different drying processes. The study also evaluated the phytochemistry, antioxidant, and antimicrobial effects of S. polycystum extracted in different solvents. Mutually under the different drying processes investigated, a total of 12 metabolites were identified from 1H NMR analysis. Freeze drying emerged as the most efficient process that preserved most of the potentially beneficial metabolites in the samples. The results of the qualitative phytochemical screening of differentially dried S. polycystum extracts revealed the presence of various secondary metabolites. The 70% ethanol extract exhibited the highest total phenolic (627 ± 50.81 mg GAE/100 g dried samples) and also displayed the highest DPPH scavenging activity (61.4 ± 0.171%) at the highest concentration (3 mg ml−1) tested. Methanol extract on the other hand contained the highest total antioxidant capacity (121.00 ± 0.003 mmol/g) followed by 70% ethanol extract (120.00 ± 0.001 mmol/g) at concentration of 1.25 mg/mL. The 70% ethanol extract also showed inhibition zone towards all bacteria samples tested compared to others solvent extracts. Based on these results, the identification of metabolites variations using PCA is considered as very useful procedure as a basis to recommend the most efficient processing (drying) method. The potential utilization of the tested Brown seaweed S. polycystum species as a source of antioxidants and antibacterial agents were also highlighted. The commercial cultivation of the species therefore, needs to be encouraged and promoted.

A collaboration between UPM and RE Millenium Sdn. Bhd. has been initiated to improve the tiger grouper E. fuscoguttatus production. For that purpose, several activities have been carried out which include field visits by university collaborators and graduate interns, discussions on different future projects with the industrial partner and workshop to train the RE Millenium staffs particularly on the live feed production and health management. Meanwhile, further research to improve the larval and juvenile production of grouper are on-going. The research involved the use of beneficial microbes through synbiotic approach and bioremediation properties.

The present invention discloses the use of Sargassum polycystum as a prebiotic agent. Accordingly, the present invention provides feed compositions or pharmaceutical compositions with prebiotic function, which comprise Sargassum polycystum in an amount of 1-3% by weight, as well as preparation methods thereof.

In the rapid expanding activities of aquaculture, advancement in fish husbandry technologies is utmost important for sustainable productivity, the critical aspects is fish health management and disease prevention. To support this industry in maintaining global competitiveness, innovation in product formulation for fish health maintenance is the focus of the present research. The research ultimate aim is product development that supports commercially important fish production through improving fish health with cascading impact on the subsequent aquaculture determinants, environmentally-friendly feeds, more efficient feeding strategies to increase production efficiencies, decrease production cost from treatment expenses, improve product quality, and minimize environmental impact. The innovation in product formulation encompassed vaccine components and preparation for application in hatcheries or farms to protect fish from a serious and detrimental haemmorhagic disease, vibriosis. Substantial economic loss from vibriosis is a worldwide aquaculture phenomenon affecting livelihood and income of farmers.

The effect of heat treatment on the superconducting properties of ErBa2Cu3O7−δ (ErBCO) ceramic materials has been studied. The nano-metal oxalate precursor was prepared using coprecipitation (COP) method. The prepared materials were subjected to calcination process at 900 °C for 12 h and then sintered under oxygen environment for 15 h at 920 °C, 930 °C, 940 °C, and 950 °C, respectively. All samples showed a metallic behavior and single-step transition in the R–T curves. The best zero critical current, T C(R=0)=91.4 K, was for the sample sintered at 920 °C. XRD data showed single phase of an orthorhombic structure. As the sintering temperature increases, the formation of nonsuperconducting phases (impurities) was observed when the samples sintered above 920 °C. The formation of nano-oxalate powders via COP method is a very efficient procedure to produce high-quality superconductors with less processing temperature required.

In this study, natural and biodegradable chitosan/agar blend gel-beads were prepared via the interphase method. Agar was added to chitosan dissolved in aqueous acetic acid and stirred homogenously under a controlled temperature. With a syringe, the gel solution were added and dropped wisely to the oily phase. The gel-beads were dried at two different conditions: in the oven at 60°C, and in the freeze dryer for 12 hours. The physicochemistry of the resulting materials were subsequently characterized by fourier transforms infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). FTIR results confirmed the formation of intermolecular hydrogen bonding between the amino and hydroxyl groups of chitosan and the hydroxyl groups of the agar. From the TGA results, we noticed that heat stability of the chitosan/agar blend beads was high compared to its individual components. SEM micrographs showed regular shaped chitosan beads with spherical forms and rough surfaces with pores.