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In this study, we determined the concentrations of water-extracted dimethylaminium (DMA + ) and trimethylaminium (TMA + ) in size-segregated atmospheric particles collected during three inland campaigns and one sea-beach campaign in Qingdao and five marine campaigns in marginal seas of China and the northwest Pacific Ocean. The averages of DMA + and TMA + in PM 0.056 – 10 (the sum of concentrations from 0.056 to 10 μm) during each campaign ranged from 0.045 to 1.1 nmol m −3 and from 0.029 to 0.53 nmol m −3 , respectively. The increased concentrations of DMA + and TMA + in PM 0.056 – 10 , particularly the 1–2 orders of magnitude increased ratios of DMA + /NH 4 + and TMA + /NH 4 + , in the marine and sea-beach atmospheres indicated that the overwhelming majority was derived from marine sources. Size distributions of TMA + and DMA + were also investigated in terms of phase states and formation pathways, e.g., the dominant modes of particulate DMA + and TMA + in some samples were characterized by the mass median aerodynamic diameter at 0.1–0.2 μm against the dominant mode of NH 4 + and SO 4 2− at 0.7–0.9 μm, while the ratios of DMA + /NH 4 + and/or TMA + /NH 4 + in <0.2 μm particles increased by 3–10 times from the corresponding lower values in >0.2 μm particles. This strongly implied that the particulate DMA + and TMA + at <0.2 μm size range overwhelmingly existed in the liquid organic phase as unprotonated TMA and DMA, but those at the >0.2 μm size range mainly existed in the aqueous (or solid) phase where the dominance of gas-aerosol equilibria would cause the ratios to be almost size-independent. The size-dependent phase states corresponded to their various formation pathways. [ABSTRACT FROM AUTHOR]

Numerous compounds, with extensive applications in biomedical and biotechnological fields, are present in the oceans, which serve as a prime renewable source of natural substances, further promoting the development of novel medical systems and devices. Polysaccharides are present in the marine ecosystem in abundance, promoting minimal extraction costs, in addition to their solubility in extraction media, and an aqueous solvent, along with their interactions with biological compounds. Certain algae-derived polysaccharides include fucoidan, alginate, and carrageenan, while animal-derived polysaccharides comprise hyaluronan, chitosan and many others. Furthermore, these compounds can be modified to facilitate their processing into multiple shapes and sizes, as well as exhibit response dependence to external conditions like temperature and pH. All these properties have promoted the use of these biomaterials as raw materials for the development of drug delivery carrier systems (hydrogels, particles, capsules). The present review enlightens marine polysaccharides providing its sources, structures, biological properties, and its biomedical applications. In addition to this, their role as nanomaterials is also portrayed by the authors, along with the methods employed to develop them and associated biological and physicochemical properties designed to develop suitable drug delivery systems. [Display omitted] [ABSTRACT FROM AUTHOR]

Marine organisms represent a valuable source of new compounds. The biodiversity of the marine environment and the associated chemical diversity constitute a practically unlimited resource of new active substances in the field of the development of bioactive products.In this paper, the molecular diversity of different marine peptides is described as well as information about their biological properties and mechanisms of action is provided. Moreover, a short review about isolation procedures of selected bioactive marine peptides is offered.Novel peptides from sponges, ascidians, mollusks, sea anemones and seaweeds are presented in association with their pharmacological properties and obtainment methods. [Copyright &y& Elsevier]

Implant materials must mimic natural human bones with biocompatibility, osteoconductivity and mechanical stability to successfully replace damaged or disease-affected bones. Synthetic hydroxyapatite was incorporated with bioglass to mimic natural bones for replacing conventional implant materials which has led to certain toxicity issues. Hence, hydroxyapatite (HAp) are recently gaining applicational importance as they are resembling the structure and function of natural bones. Further, nanosized HAp is under extensive research to utilize them as a potential replacement for traditional implants with several exclusive properties. However, chemical synthesis of nano-HAp exhibited toxicity towards normal and healthy cells. Recently, biogenic Hap synthesis from marine and animal sources are introduced as a next generation implant materials, due to their mineral ion and significant porous architecture mediated biocompatibility and bone bonding ability, compared to synthetic HAp. Thus, the purpose of the paper is to give a bird's eye view into the conventional approaches for fabricating nano-HAp, its limitations and the significance of using marine organisms and marine food wastes as a precursor for biogenic nano-Hap production. Moreover, in vivo and in vitro analyses of marine source derived nano-HAp and their potential biomedical applications were also discussed. • Biowastes as a source of calcium for the fabrication of nanohydroxyapatite are widely used in recent times. • Nanosized hydroxyapatite particles are recommended in the field of biomedical, due to their similarity as natural bones. • Absence of harmful substances in nano-Hap synthesized via biogenic sources is considered as safe biomaterial. • Synthesis, properties and applications of conventional and biological nano-Hap was reviewed. [ABSTRACT FROM AUTHOR]

• Hydroxyapatite (HAp) synthesized by chemical methods, and it used for bone tissue engineering. • HAp synthesized from the biowaste and natural biopolymers. • HAp nanocomposites for biomedical and regenerative applications. • Improve the mechanical properties of implants due to their presence of a microporous matrix. Regenerative medicine is becoming a fast-growing technique in today's scenario for biomedical advancement. Researchers around the globe has suggested the involvement of naturally synthesized biomaterials for repairing and healing damaged cells. Already chemically synthesized hydroxyapatite (HAp) has been used for bone tissue engineering. But the low stability and durability of HAp have reduced their feasibility of application in the biomedical sector. These disadvantages of chemically and physically synthesized hydroxyapatite led to the use of natural biowaste, and biopolymer for the synthesis of HAp. Biologically synthesized HAp are potential replacement in biomedical engineering and regenerative drugs. These HAp are readily biodegradable, biocompatible correlated to macromolecules, making them easy for the incorporation in inorganic materials. The review article provides comprehensive knowledge about the various naturally derived biopolymers, especially HAp. The methods of preparing implants contain natural biopolymers and calcium phosphate composites used in various biomedical applications, such as bone tissue engineering, cartilage, vascular graft, and other implantable biomedical devices. [ABSTRACT FROM AUTHOR]