What marine life produces antibiotics that can counter oral pathogens?5 answersMarine bacteria and fungi have been found to produce antibiotics that can counter oral pathogens. Marine bacteria belonging to the genera Streptomyces, Nocardiopsis, and Alteromonas have shown significant antibiotic activity against oral pathogens such as Staphylococcus aureus, Escherichia coli, and Candida albicans. Marine fungi, particularly strains of the genera Penicillium, Emericellopsis, and Simplicillium, have also demonstrated antibacterial and antifungal properties, making them potential sources of antibiotics against oral pathogens. These findings highlight the potential of marine bacteria and fungi as valuable resources for the development of new antibiotics to combat oral pathogens and drug resistance.
Main sources of pollutants entering ocean water?4 answersThe main sources of pollutants entering ocean water include land-based sources such as coastal discharges, inland sources that flow into the sea through rivers or canals, and airborne sources carried via the atmosphere. These sources contribute to marine pollution through direct and indirect means. Dumping at sea is another significant source of pollution, involving the deliberate disposal of waste or other matter from vessels, aircraft, platforms, or man-made structures. Pollution of the oceans is widespread and poorly controlled, with more than 80% of pollutants arising from land-based sources. These pollutants include toxic metals, plastics, manufactured chemicals, petroleum, urban and industrial wastes, pesticides, fertilizers, pharmaceutical chemicals, agricultural runoff, and sewage. Other sources of pollution include oil and oil products, water acidification, thermal pollution, electromagnetic pollution, radioactive pollution, chemical pollution, and biological pollution. Municipal wastewater can also transport pollutants to the marine environment, including UV filters, synthetic volatile fragrances, and microplastics.
What are the impacts of microplastics on marine ecosystems?3 answersMicroplastics have been found to have impacts on marine ecosystems. They can cause toxic effects, reduced food intake, delayed growth, oxidative damage, abnormal behavior, and genetic damage in fishes, affecting them at molecular levels. The wide distribution of micro- and nano-sized plastic particles in the World Ocean is of particular concern, as they contribute to biological effects and pose a serious threat to marine ecosystems and biota. Microplastics have been consistently found associated with the biota, water, and sediments of coral reefs, and there is a knowledge gap regarding nanoplastic levels, which are thought to pose the greatest risk due to their ability to translocate into different organs. The impacts of microplastics have been observed across all taxa and trophic levels, from phytoplankton to marine mammals, and there is a need to understand the ecotoxicological effects on the health of aquatic organisms. Therefore, it is important to prioritize research and mitigation efforts to prevent and reduce plastic pollution in marine ecosystems.
What are the effects of microbial activity on seawater ?5 answersMicrobial activity in seawater has various effects. It can stimulate heterotrophic activity and increase microbial abundance. Additionally, microbial activity can induce primary productivity rates and promote the growth of specific microbial groups, such as Synechococcus. Microbes delivered by submarine groundwater discharge (SGD) can also affect the abundance, activity, and diversity of intrinsic microbes in coastal seawater. Furthermore, microbes play a role in the geochemical interactions between seafloor massive sulfide (SMS) deposits and seawater, influencing the dissolution of metals and the removal of phosphorus. In terms of seawater desalination, microbial activity in biofilters can reduce biofoulants through adsorption and biodegradation, leading to the removal of dissolved organic carbon (DOC) and the reduction of biofouling potential. Overall, microbial activity in seawater has important implications for nutrient cycling, carbon fluxes, and the overall functioning of marine ecosystems.
How exposure of human for antibiotic resistance in oceans?5 answersExposure of humans to antibiotic resistance in oceans is a significant concern. Plastic pollution in marine environments has been associated with an enrichment in pathogenic bacteria and antimicrobial resistance (AMR) genes. Chemicals leached from plastic particles alone can enrich genes related to microbial pathogenesis within a bacterial community. Antibiotic compounds and other pollutants in coastal environments can lead to the selection of resistant bacteria and the evolution of AMR. Antibiotic resistant bacteria have been detected in natural aquatic environments, including marine environments. Marine environments host a diversity of genes conferring resistance to antibiotics, with some of these genes found in abundant marine taxa. Ingestion of seawater during water sports is one route by which people can be directly exposed to antibiotic resistant bacteria. Overall, the presence of antibiotic resistance in oceans poses a risk to human health and highlights the need for global solutions to address this issue.
Is pyridine toxic to aquatic life?5 answersPyrethroid insecticides, such as pyrethroids, have high toxicity to fish and some aquatic invertebrates under laboratory conditions. However, their bioavailability to aquatic organisms is greatly reduced in the adsorbed state when they are strongly adsorbed to particulate material. Therefore, under field conditions, the aquatic impact of pyrethroids is likely to be much less than predicted by laboratory toxicity test data.