Special issue. (Special issue.)

This special issue contains 17 papers covering a range of topics related to environmental, geological, and social issues in Bangladesh. The articles use various methodologies, including statistical analysis, satellite imaging, and case studies, to explore issues such as drought, urbanization, healthcare, greenhouse gas emissions, groundwater resources, COVID-19 stigmatization, oil rim reservoir development, coal permeability, seaweed composition, hailstorms, tropical cyclones, heavy metal contamination, flood hazard assessment, and climate change vulnerability. Overall, the articles provide valuable insights and information that can inform policy and decision-making in Bangladesh.

Aquaculture: an introductory text

This 4th edition covers issues associated with sustainable aquaculture development, culture systems, hatchery methods, nutrition and feeding of aquaculture species, reproductive strategies, harvesting, and many other topics. While its main focus is on the culture of fish, molluscs and crustaceans for food, the book also covers other forms of aquaculture, such as the production of seaweeds, recreational fish and ornamental species, as well as live foods, such as algae and rotifers that are used to feed larval shrimp and marine fish. Thoroughly updated and revised, this essential textbook now includes increased coverage of open-ocean cage culture and sea lice issues with salmon culture, coverage of the significant progress made in nutrition, including the move away from fishmeal as protein and fish oil as lipids in feed, information on biofloc technology uses, predictive impacts of climate change, probiotics, and the impact of COVID-19 on the aquaculture community, and updated aquaculture production statistics and lists of approved anaesthetics. Aquaculture remains one of the most rapidly growing agricultural disciplines, and this book remains an essential resource for all students of aquaculture and related disciplines.

A state-of-the-art review on fucoidan as an antiviral agent to combat viral infections.

As a significant public health hazard with several drug side effects during medical treatment, searching for novel therapeutic natural medicines is promising. Sulfated polysaccharides from algae, such as fucoidan, have been discovered to have a variety of medical applications, including antibacterial and immunomodulatory properties. The review emphasized on the utilization of fucoidan as an antiviral agent against viral infections by inhibiting their attachment and replication. Moreover, it can also trigger immune response against viral infection in humans. This review suggested to be use the fucoidan for the potential protective remedy against COVID-19 and addressing the antiviral activities of sulfated polysaccharide, fucoidan derived from marine algae that could be used as an anti-COVID19 drug in near future.

Cyanobacteria and Algae-Derived Bioactive Metabolites as Antiviral Agents: Evidence, Mode of Action, and Scope for Further Expansion; A Comprehensive Review in Light of the SARS-CoV-2 Outbreak.

COVID-19-a severe acute respiratory syndrome disease caused by coronavirus 2 (SARS-CoV-2)-has recently attracted global attention, due to its devastating impact, to the point of being declared a pandemic. The search for new natural therapeutic drugs is mandatory, as the screening of already-known antiviral drugs so far has led to poor results. Several species of marine algae have been reported as sources of bioactive metabolites with potential antiviral and immunomodulatory activities, among others. Some of these bioactive metabolites might be able to act as antimicrobial drugs and also against viral infections by inhibiting their replication. Moreover, they could also trigger immunity against viral infection in humans and could be used as protective agents against COVID-In this context, this article reviews the main antiviral activities of bioactive metabolites from marine algae and their potential exploitation as anti-SARS-CoV-2 drugs.

Moving seaweed farms from shallow to deep seawater to cope with warming and diseases in Zanzibar. Current socio-economic and cultural barriers

This study aimed at identifying the climate and non-climate stressors affecting the seaweed farming practices. It also examines the deep water seaweed farming as a viable adaptation measure to these stressors and barriers that could constrained female seaweed farmers who are the majority. The study was carried out in six selected groups, two groups were from South District, Unguja Main Island (Furahiya Wanawake-Paje and Flower Group-Muungoni). And four groups were selected from Pemba Island (Tuwe Imara and Umoja Kazi- East Msuka and Ipo sababu and Umoja ni Nguvu - East Tumbe) from Micheweni District. These groups were selected because they participated in previous project implemented by Milele Zanzibar Foundation (MZF) and The Panje Project (TPP). Questionnaire interview collected various information related to the study from 111 seaweed farmers who are members of these groups. Information such as baseline seaweed production, climate change and diseases that affect seaweed production, farmer's awareness on moving seaweed farms to deep water to cope with increasing warming and diseases and their capacity to swim as prerequisite for the adoption of this coping strategy. The focal group discussions were conducted in all six groups to collect various information to triangulate the findings collected from the questionnaire interview. The data obtained from three methods analyzed using descriptive statistics. The findings show that seaweed farming production has declined at least over the last seven years. Climate change and its variability, diseases, over utilization of shallow water space for farming seaweed, COVID 19 and price has contributed a lot in the observed decline. Deep water (0.5 meter during low tide and 3-5 meters during high tide) seaweed farming seen as viable option to cope and adapt to increasing warming and diseases but its adoption especially amongst female seaweed farmers constrained by their limited capacity to swim and their limited ownership of the vessels. The study also identified other barriers such as age, gender and cultural factors that could constrained female seaweed farmers from participation in swimming and sea safety training. To facilitate adoption of the deep-water seaweed farming method amongst the seaweed farmers, concerted effort should be made to overcome the barriers that are likely to limit the massive adoption of this method.

Research Progress in Anti-Inflammatory Bioactive Substances Derived from Marine Microorganisms, Sponges, Algae, and Corals.

Inflammation is the body's defense reaction in response to stimulations and is the basis of various physiological and pathological processes. However, chronic inflammation is undesirable and closely related to the occurrence and development of diseases. The ocean gives birth to unique and diverse bioactive substances, which have gained special attention and been a focus for anti-inflammatory drug development. So far, numerous promising bioactive substances have been obtained from various marine organisms such as marine bacteria and fungi, sponges, algae, and coral. This review covers 71 bioactive substances described during 2015-2020, including the structures (65 of which), species sources, evaluation models and anti-inflammatory activities of these substances. This review aims to provide some reference for the research progress of marine-organism-derived anti-inflammatory metabolites and give more research impetus for their conversion to novel anti-inflammatory drugs.

Potential Antiviral Properties of Industrially Important Marine Algal Polysaccharides and Their Significance in Fighting a Future Viral Pandemic.

Over the decades, the world has witnessed diverse virus associated pandemics. The significant inhibitory effects of marine sulfated polysaccharides against SARS-CoV-2 shows its therapeutic potential in future biomedical applications and drug development. Algal polysaccharides exhibited significant role in antimicrobial, antitumor, antioxidative, antiviral, anticoagulant, antihepatotoxic and immunomodulating activities. Owing to their health benefits, the sulfated polysaccharides from marine algae are a great deal of interest globally. Algal polysaccharides such as agar, alginate, carrageenans, porphyran, fucoidan, laminaran and ulvans are investigated for their nutraceutical potential at different stages of infection processes, structural diversity, complexity and mechanism of action. In this review, we focus on the recent antiviral studies of the marine algae-based polysaccharides and their potential towards antiviral medicines.

The Anti-Viral Applications of Marine Resources for COVID-19 Treatment: An Overview.

The ongoing pandemic has led to an urgent need for novel drug discovery and potential therapeutics for Sars-CoV-2 infected patients. Although Remdesivir and the anti-inflammatory agent dexamethasone are currently on the market for treatment, Remdesivir lacks full efficacy and thus, more drugs are needed. This review was conducted through literature search of PubMed, MDPI, Google Scholar and Scopus. Upon review of existing literature, it is evident that marine organisms harbor numerous active metabolites with anti-viral properties that serve as potential leads for COVID-19 therapy. Inorganic polyphosphates (polyP) naturally found in marine bacteria and sponges have been shown to prevent viral entry, induce the innate immune response, and downregulate human ACE-2. Furthermore, several marine metabolites isolated from diverse sponges and algae have been shown to inhibit main protease (Mpro), a crucial protein required for the viral life cycle. Sulfated polysaccharides have also been shown to have potent anti-viral effects due to their anionic properties and high molecular weight. Likewise, select marine sponges produce bromotyrosines which have been shown to prevent viral entry, replication and protein synthesis. The numerous compounds isolated from marine resources demonstrate significant potential against COVID-19. The present review for the first time highlights marine bioactive compounds, their sources, and their anti-viral mechanisms of action, with a focus on potential COVID-19 treatment.