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Chitin extraction from crab shells was studied experimentally and optimized aiming to obtain chitosan with predefined deacetylation degree and molecular mass. To find out the optimum operating conditions that ensure the obtaining of a chitosan with highest deacetylation degree and specific molecular mass four parameters were varied: the concentration of NaOH and the temperature for deproteinization step, respectively HCl concentration and the number of acidic treatments for the demineralization stage. The experiment was carried on following Taguchi orthogonal array L9, and the best combination of factors was found using the desirability function approach. The optimization results showed that 5% NaOH concentration and low temperatures lead to a chitosan with high deacetylation degree. High molecular mass chitosan is obtained when a single step acidic treatment is used, while a chitosan with low molar mass is obtained for multiple acid contacts and higher HCl concentration.

The present study evaluated the structural and ultrastructural characteristics of Rapana venosa egg capsules, starting from observations of their antifouling activity and mechanical resistance to water currents in mid-shore habitats. Optical microscopy, epifluorescence, and electron microscopy were used to evaluate the surface and structure of the R. venosa egg capsules. These measurements revealed an internal multilamellar structure of the capsule wall with in-plane distributions of layers with various orientations. It was found that the walls contained vacuolar structures in the median layer, which provided the particular characteristics. Mechanical, viscoelastic and swelling measurements were also carried out. This study revealed the presence and distribution of chitosan in the capsule of R. venosa. Chitosan identification in the egg capsule wall structure was carried out through SEM–EDX measurements, colorimetric assays, FT-IR spectra and physical–chemical tests. The biopolymer presence in the capsule walls may explain the properties of their surfaces as well as the mechanical resistance of the capsule and its resistance to chemical variations in the living environment.

Development of physical-chemical analysis methods has led to detection many chemical compounds (microplastics, pesticides, steroids, hormones, contraceptives, fragrances, sunscreen agents, water disinfection by products, gasoline additives, pharmaceutical formulations used in the treatment of human and veterinary affections, corrosion inhibitors, biocides, UV-filters, etc.) into the marine environment, called emerging pollutants. Their release into the environment was caused by industrial overgrowth, an excessive modernization of agriculture and the development of maritime transport. The large number of chemicals and compounds from surface waters, soils, groundwaters, and sediments is seen as a potential threat to human health because their presence is not widely regulated or monitored by national and international legislation. The emergence of these compounds is due to the increase of concern degree due to the impact they produce on the environment, as a result of their presence in a wide types variety and at different concentrations. The present paper aims to compile available data about the occurrence, sources, and impact of emerging pollutants to improve the analytical methods for detecting more contaminants, to establish new guideline values useful for human health and marine environment protection.

New green and sustainable sources were chosen to obtain chitosan, an important material, with many applications in different fields. The present study is focused on egg capsules of Rapana venosa waste as raw material for chitosan oligomers. As previous studies revealed that chitosan extraction from this material takes place with a low yield, the present research aimed to optimize this step. A 22 experimental plan, with three replicates in the center, was proposed to investigate the influence of NaOH concentration and temperature on the yield extraction. After a primary analysis of the experimental data, a favorable temperature value was selected (90 °C) at which the total dissolution of the egg capsules was obtained. Then, at this temperature, the experimental plan was extended exploring the influence of the NaOH concentration on three levels (5, 6, and 7%) and the extraction duration on two levels (60 and 85 min). Based on all experimental data, a neural model was obtained and validated. The neural model was used to maximize the yield, applying Genetic Algorithm (GA) implemented in Matlab®. The resulting optimal solution is: NaOH concentration 6.47%, temperature 90 °C, duration 120 min, with a yield value of 7.05%.

The efficiency of different procedures or the quality of different products could be enhanced by optimizing the production process steps. In this paper, experimental investigations using a Taguchi ...

Chitosan, one of the most interesting and intriguing biopolymer, can be extracted from different marine waste. The present paper focuses on the chitosan extraction procedure from Macropipus holsatus crab waste. Because the deacetylation degree is the most important characteristic of chitosan, the influence of specific operating parameters during deacetylation treatment was analyzed by statistical analysis and mathematical modelling using artificial neural networks (ANN). The ANN simulation put into evidence the manner that the deacetylation degree is influenced by the considered operating conditions and enabled the identification of optimal operating conditions in order to obtain a chitosan with a relatively high deacetylation degree. The obtained chitosan was characterized by various methods, including physical-chemical analysis, structure identification and crystallinity index. The main effects as well as the interaction effects for some physical-chemical properties were studied to establish if and how the chitosan properties are affected by the extraction procedure.

Identification of chitosan from new local marine sources could be a great challenge for research in terms of using this biopolymer in various pharmaceutical, environmental or food applications. In the present study, two chitosan powder samples extracted from processed shrimps waste and Rapana venosa eggs capsules were compared with a food supplement sample based on chitosan, from the point of view of spectral analyses (FTIR spectroscopy), of their solubility in dilute acetic acid solutions (1 %), insoluble substances content, and fats binding capacity. In order to determine the fat binding capacity of the tested chitosan samples, different types of cold pressed vegetables oils (olive oil, sunflower oil, soybean oil, argan oil and coconut oil) and animal fats (butter and pork lard) were used. The present study highlighted that the chitosan samples, chemically extracted with low financial efforts by waste recovery of crustaceans and mollusks from Romanian Black Sea coast, could be an important source with high potential. The obtained results showed a good fat binding capacity, especially for chitosan samples extracted from shrimps waste compared to the chitosan sample chosen as reference. These compounds may be successfully used in pharmaceutical applications, in various formulations as dietary supplement, or as useful therapeutic component in the hypocholesterolemia treatment or in prevention of cardiovascular risk, due to their good solubility in dilute acidic solutions and lower values of insoluble content.

"The floral tips of the plant species Lythrum salicaria L. represent a rich source of total polyphenols, among which with the largest share we mention tannins, and this is why this plant material has a standardized monograph in the European Pharmacopoeia 10.0th edition. According to the literature accessed so far, the plant material has antioxidant, anti-inflammatory, hemostatic, antibacterial and antifungal properties, along with modulatory action on carbohydrate metabolism. Powder microscopic examination is an important step in establishing the identity of the plant species used, highlighting elements specific to the aerial part such as spiral vessels of the stem, fragments of the spongy mesophyll with calcium oxalate clusters cells and anomocytic stomata. The application of the SeDeM method on dried plant extracts represents an innovative trend in pharmaceutical technology and contributes to the collection of data in a structured and standardized form. In this paper, the functions and applications of the SeDeM expert system are illustrated upon the freeze-dried extract of Lythri herba for the purpose of easier identification and standardization. Future applications may include obtaining chewable gums or tablets by direct compression."

"Nowadays we are witnessing an increased interest in phytotherapy and implicitly for herbal products that have lower side effects. One medicinal plant whose popularity has decreased significantly in recent years is Lythrum salicaria L., loosestrife, known in Romanian traditional medicine for its beneficial effects against gastrointestinal diseases. The aim of this study is to evaluate the biological activity of three different extracts (aqueous, alcoholic, acetonic) from the flower tips of Lythrum salicaria L. using the BSLA (Brine Shrimp Lethality Assay) test and the antimicrobial activity of the extracts on two reference bacterial strains which are important for the medical field (Staphylococcus aureus and Escherichia coli) through the diffusimetric method. We demonstrated the fact that the Lythri herba plant product extracts (aqueous, alcoholic, and acetonic) lack acute toxicity, as well as the moderate antibacterial effect on the Gram-positive reference strain, Staphylococcus aureus, thus highlighting the possibility of using the plant in biomedical applications."

"The Lythrum salicaria L. plant, from the Lythraceae family, has multiple beneficial effects on the human body, through pharmacological properties imprinted by its secondary metabolites, namely tannins. Chitosan-based biomedical materials are of increasing interest precisely due to the uniqueness of their properties, namely biocompatibility, nontoxicity, biodegradability, antimicrobial and antioxidant nature. The combination of chitosan with the plant extract aimed at obtaining new matrices, with clearly superior characteristics, compared to each material (chitosan and plant extract). This could be due to the presence of amino groups in the structure of chitosan, known to be active at a pH slightly acidic and which could be chemically bound to the phenolic groups of tannic acids (the predominant components of the plant extract). The study aimed to obtain for the first-time mixtures of different concentrations of aqueous solutions of Lythri herba plant extract with standard chitosan 1 % in lactic acid (1 %) solution, which allowed achieving compatible and stable membranes. Microscopic evaluation of the membranes were made, following the uniformity of the surfaces, the homogeneity, the distribution of chitosan relative to the extract, and their stability in PBS saline buffer. The behavior of these membranes gives us a perspective on their use in dentistry and pharmaceuticals. In addition, the current paper has shown the existence of chitosan in the composition of the obtained membranes and their ability to maintain constant hydration and flexibility over a certain period."

New chitosan powder extracted from eggs capsules of Rapana venosa and commercial chitosan powder were analyzed by spectral (UV–Vis) and color methods. The novelty of this study consists in the first time toxicity evaluation of the chitosan extracted from the walls of Rapana venosa eggs capsules. The evaluation was focused on the cytological behaviour of the new-chitosan particles in two different salinity conditions (3 and 35‰), at different concentrations, on bio tester organisms. The aim of this study was to determine the biological effect of the chitosan easily extracted from new marine sources and with a low financial effort. The experimental studies were performed by exposure of Artemia salina larvae, naupliar stage in saline chitosan solutions. The larvae were picked-up in 24 h time, after hatching and they were placed in the experimental recipients of 1 mL volume capacities, three repetitions were made for each test. The bioassay effects were recorded at 24 and 48 h after experiment started. The toxicity was indicated by the registration of larvae mortality, probably, induced by the cell growth inhibitions. The obtained results showed that the high toxicity effects could be observed at low concentrations of chitosan, in law salinity solutions. Due to this cytotoxicity variability, chitosan solutions could be useful in a wide range of applications (antifouling, biomedical or sewage cleaning).

This paper presents the chemical extraction of two marine polysaccharides (chitin and chitosan) from one of the crustacean species of Romanian Black Sea waters. The characterization of these polysaccharides were studied through optical microscopy and FT-IR/ATR spectroscopy. The spectra samples were compared with those of chitin and chitosan standards and results showed the presence of chitin and chitosan in the studied samples.

The Romanian Black Sea environment, due to its biodiversity, contains a lot of organism, which represents a rich natural resource of many biologically active compounds, such as: sterols, proteins, polyunsaturated fatty acid, polysaccharides, pigments and antioxidants.In their evolution, marine organisms in the Black Sea adapted excellently to the marine environment such as: low temperature, absence of light, extreme pH and pressure, low salinity, low oxygen, the presence of one toxic abiotic chemical (H2S). Moreover, they produce a wide variety of secondary metabolites (biologically active), which cannot be found in other terrestrial organisms.Chitosan is a copolymer of β-(1→4)-linked 2-acetamido-2-deoxy-D-glucopyranose and 2-amino-2-deoxy-D-glucopyranose. Usually, it is obtained by deacethylation of the natural chitin, which is extracted from the exoskeleton of marine organisms, mainly crabs and shrimps. Chitosan could have a lot of applications in biomaterials, pharmaceuticals, cosmetics, metal ...

The subject of this paper is to analyze the hydrometeorological parameters received on board during on route from Singapore to Santos (Brazil) between July 15th and August 4th, 2018 to optimize fuel consumption on board. The information was obtained daily, in real time, using on-board measurement tools and SPOS 8 Software provided by MeteoGroup, and those related to fuel consumption in the EcoVoyage program. General analyzes of hydrometeorological parameters were introduced as graphs, with more detailed values extracted from MSPS (Maersk Ship Performance System).

Marine organisms are formed by bio compounds with a lot of properties and characteristics that may justify their potential applications within the biomedical field. Assuring the exploitation of natural marine resources and the valorization of residues from marine origin, like those obtained from food processing, represent a highly interesting platform for development of novel eco-friendly biomaterials, with higher benefits due to the fact that the source is practically inexhaustible. This study involves the extraction and identification of chitosan from samples of invertebrates organisms by chemical extraction method. The samples of aquatic organisms consist of exoskeleton of crab and spawning of gastropoda. This paper presents the possible raw materials for production of chitosan extracted from marine organisms and the characterization of the chitosan extract.