Seaweeds, also known as macroalgae, are abundant sources of various vital bioactive components with a wide range of biological functions. They are sold commercially and are primarily used in the food industry, pharmaceuticals, cosmeceuticals, and other related industries. The diverse biological activities linked with bioactive compounds obtained from seaweeds have the potential to expand their health benefit value in the food and pharmaceutical industries. Studies revealed that seaweeds have the potential to be used as complementary medicine due to its variety of biological properties that have been shown to be therapeutic for health and disease management, such as antibacterial, anticoagulant, anticancer, antidiabetic, antiestrogenic, antihypertensive, antihyperlipidemic, antifungal, anti-inflammatory, antioxidant, antiobesity, antiviral, immunomodulatory, neuroprotective, thyroid stimulant, tissue healing properties, and many more. Although seaweeds are generally beneficial to humans, they may still pose possible health risks due to high iodine concentration and exposure to heavy metals and arsenic concentrations. However, information on this topic is still limited. With the great importance of seaweeds, various green extraction methods such as Microwave-assisted Extraction (MAE), Supercritical Fluid Extraction (SFE), Pressurized Solvents Extraction (PSE) and Enzyme-ssisted Extraction (EAE) were used as an alternative to the conventional method to isolate bioactive components and further purified using chromatographic technique analysis to ensure the purity of the extract. This review covers the following topics: general structure and characteristics of seaweeds, seaweed production, bioactive components and properties of seaweed, possible risk factors of seaweeds, applications of seaweeds, extraction, and purification of seaweed extracts.

Limpets are common inhabitants of the midlittoral and upper infralittoral zones and play an important ecological role in the coastal ecosystem. The study aimed to assess growth, meat yield, morphological aspects, condition and reproduction features of Patella caerulea. About 58% of collected Mediterranean limpets were concentrated in the 25.0-34.9 mm shell length group. The average meat yield ratio was calculated as 39.34%. Mean growth increments for shell length (SL) and total weight (TW) were 23.99% and 97.99%, respectively. Results exhibited relatively high correlation coefficients among variables. Mean condition factor value was calculated as 14.2. Spawning occurs over a short period with ovigerous females observed on two month periods. Mean fecundity was calculated as 90,983±28,675 eggs/g whereas mean egg diameter was estimated as 160.6 μm. This study presents first baseline information about biological and morphological of Mediterranean Limpets population in Black Sea.

This study assessed the length-frequency distribution and condition factor of Brycinus nurse from two sampling stations in the New Calabar River. A total of 401 individuals of B. nurse were collected from artisanal fishers and assessed between February 2020 and January 2021. The collected samples were analyzed for growth pattern using FISAT II. The mean values were 11.80±1.59 cm and 9.52±1.28 cm for total length and standard length The mean weight was 20.63±8.38 g. The length-weight relationship revealed an exponent b value of 2.539, showing negative allometric growth. The condition factor ranged from 1.09 to 1.42 indicating that the species is in good growth condition. The size structure of B. nurse recorded indicated that most individuals were relatively medium to small sizes and were not allowed to grow to adults as a result of overfishing. Therefore, proper management and intervention is needed to manage overexploitation of B. nurse in the New Calabar River.

Frigate tuna Auxis thazard (Lacepède, 1800) is the most dominant species caught by the multiple handline in the coastal and offshore fishing grounds of Tawi-Tawi, southern Philippines. In this study, we investigated the size distribution, length-weight relationship, and catch per unit effort of frigate tuna (A. thazard) in Tawi-Tawi waters, southern Philippines, caught using multiple handline. A total of 383 frigate tuna fish were sampled with a size distribution (total length) ranging from 16.5 to 34 cm. The length-weight relationship of frigate tuna was W=8×10-3×TL3.139, where the b value of 3.139 indicates a positive allometric growth pattern. The catch per unit effort of the used gear was 2.49±0.52 kg/hr.

In the study, the production, foreign trade, and competitiveness of the countries, which have an important share in world aquaculture production, were examined. According to the 2019 data shows that Chine and Indonesia are the most important aquaculture producers in the world. The data set belonging to 2010-2019 was used in the research. In the study, Revealed Comparative Advantage (RCA), Vollrath Relative Export Advantage Index (RXA), Relative Trade Advantage Index (RTA), Relative Competitiveness Index (RC), Relative Import Advantage Index (RMA), and Trade Balance Index (TBI) indices were used. According to the index results, it is concluded that Turkey is advantaged in terms of fresh and chilled fish foreign trade competition. Turkey has an importer position in world frozen fish and other aquaculture trade.

Anchovy (Engraulis encrasicolus L., 1758) is the main source of fishmeal in Turkey. The research was carried out in 3 fishmeal factories where anchovy is processed in the Black Sea during the 2007-2008 fishing season. Factories A and B have an evaporator system, while factory C does not have an evaporator system. In the study, it was aimed to reveal the effect of the evaporator system on the mineral substance quality of the fishmeal produced in fishmeal oil factories. As a result of this study, the elements in fishmeal are listed in descending order as Ca>P>K>Na>Mg>Fe>Zn>Mn>Cu. According to the results of the research, it was determined that the phosphorus, sodium, potassium, calcium and zinc values of fish fishmeal produced in A and B factories using evaporator system were higher than the C factory without an evaporator system, and the difference between factories was statistically significant (P<0.05). It is recommended that all factories have an evaporator system in order to produce fishmeal of higher quality (protein and mineral substances) in fishmeal-oil factories.

This study was conducted between July 2016 and 2017 to determine the growth and survival rates of the smooth scallop Flexopecten glaber spats in Urla Karantina Island. The sea water temperature was determined as 21.56±6.33°C, 21.1±6.40°C and 20.87±6.35°C at 2, 4 and 6 m depths, respectively. Salinity values varied between 36 and 38.19 PSU in the region. The highest chlorophyll-a value was determined as 8.95 µg l-1 in August at 2 m depth and 1.65 µg l-1 as the lowest at 4 m depth in January. Average values of total particulate matter amount were calculated as 4.41±1.86 mg l-1, 5.09±1.88 mg l-1 and 5.47±1.89 mg l-1 at 2, 4 and 6 m depth, respectively. Scallop spats with an average height of 8.26±1.55 mm were measured at the beginning of the study. The heights of the smooth scallop spats, which were placed at 2 m, 4 m and 6 m depths in the study area, were 42.6±1.11 mm, 41.53±12.85 mm and 41.57±1.64 mm and their weights were measured as 12.71±0.89 g, 12.85±0.53 g and 12.82±1.00 g, respectively. While the survival rate was 53% placed at 2 m depth in the study area, the lowest survival rate was found as 37% for the spats grown at 6m depth. The result showed that the mean values of height at the surface depth (2 m) were more significant than those at the other depths (4 m and 6 m). However, there were no statistically significant differences between the depths and specific growth rate (SGR) for height and weight (p>0.05). But SGRh and SGRw values at each depth showed statistically significant differences between months (p<0.05).

Mental workload (MWL) has a negative effect on the functional states of watchkeeping officers that ultimately causes collisions and groundings at sea. The aim of this study is to measure the MWL of officers during different navigation conditions. This study was conducted in a bridge simulator with 11 participants. Heart rate variability (HRV) measurements were taken during the 4 steps which have different difficulty levels and subjective assessments were taken at the end of each step by using NASA-TLX. The results of the measurements showed that different levels of navigation tasks caused significantly different levels of MWL and HRV values and MWL and HRV increased when task difficulty increased. Additionally, the correlation between MWL perceived by the participants and the heart rate variability values of the participants was found statistically significant. This study provides an example of predicting MWL for routine navigation operations by using physiological measures in maritime transportation.

The aim of this study was to determine the in vitro inhibitory effects of some metal ions (silver ion (Ag+), cadmium ion (Cd2+), cobalt ion (Co2+), copper ion (Cu2+), nickel ion (Ni2+), lead ion (Pb2+) and zinc ion (Zn2+)) on glutathione reductase (GR) enzyme activities that purified from the gill, kidney and liver tissues of Capoeta umbla. For this purpose, the enzyme was purified from the gill, kidney and liver of C. umbla freshwater fish using ammonium sulfate precipitation and affinity column chromatography methods using 2′,5′-ADP Sepharose 4B. Within this study, the GR enzyme was purified for the first time from the tissues of C. umbla. Enzyme purity and molecular weight were determined using the sodium dodecyl sulfate polyacrylamide gel electrophoresis method. In addition, the inhibitory effects of different metal ions (Ag+, Cd2+, Co2+, Cu2+, Ni2+, Pb2+ and Zn2+) on GR enzyme activities of the gill, kidney and liver tissue of C. umbla were investigated under in vitro conditions. The metal ion concentrations inhibiting 50% of enzyme activity (IC50) were obtained by plotting activity percentage versus [I] figures. Finally, the dissociation constants of the enzyme inhibitor complex (Ki), and the inhibition types, were calculated from Lineweaver–Burk plots. In vitro inhibition rank order was determined as Ag+>Co2+>Pb2+>Zn2+>Cu2+ for C. umbla gill GR; Ag+>Pb2+>Co2+> Ni2+>Zn2+ for C. umbla liver GR; Ag+>Cu2+>Co2+>Pb2+>Ni2+ for C. umbla kidney GR. From these results, we showed that Ag+ metal ion is the most potent inhibitor of GR enzyme on gill, liver and kidney tissues. Our results also demonstrate that these metals might be dangerous at low micromolar concentrations for C. umbla GR enzyme.

The present study reports in silico investigation of bioactive compounds from marine microalgae capable of escalating copepod fecundity potential through enhanced heat shock protein (HSP-70) production. The structure of ligand (bioactive compounds from microalgae) and hsp-70 obtained from the databases of PubChem and Protein Data Bank (PDB), respectively. Molecular Docking was performed by GOLD software and ligand interaction pathways using web server MANORAA. Fourteen bioactive compounds showed good biding interaction with specific protein HSP-70 and seven of these compounds showed high hydrogen bond interaction with key amino acids (phenylalanine, tyrosine and tryptophan). The highest binding energy of 50.21 is recorded in the bioactive compound, arachidonic acid from the red alga Porphyridium cruentum TYR 167 involved in the biosynthesis pathway of phenylalanine, tyrosine and tryptophan also showed specific target site of tryptophan synthase (4.2.1.20). Results suggest with P. cruentum feed copepod culture could boost their fecundity leading to high density culture.