The incidence of eutrophication is increasing due to fertilizer abuse and global warming. Eutrophication can induce the proliferation of cyanobacteria such as Microcystis, which produces microcystins. Microcystins are toxic to specific organs such as the liver and the heart. Thus, monitoring of microcystins is strongly required to control drinking water and agricultural product qualities. However, microcystins could be adsorbed by plastic materials during sample storage and preparation, hindering accurate analysis. Therefore, the current study examined the recovery rate of microcystins from six plastics used for containers and eight plastics used for membrane filters. Among the six plastics used for containers, polyethylene terephthalate showed the best recovery rate (≥81.3%) for 48 h. However, polypropylene, polystyrene, and high- and low-density polyethylenes showed significant adsorption after exposure for 1 hr. For membrane materials, regenerated cellulose (≥99.3%) showed the highest recovery rate of microcystins, followed by polyvinylidene fluoride (≥94.1%) and polytetrafluoroethylene (≥95.7%). The adsorption of microcystins appeared to be strongly influenced by various molecular interactions, including hydrophobic interaction, hydrogen bonding, and electrostatic interaction. In addition, microcystins’ functional residues seemed to be critical factors affecting their adsorption by plastic materials. The present study demonstrates that polyethylene terephthalate and regenerated cellulose membrane are suitable plastic materials for the analysis of microcystins.

The aim of this study was to assess the risk of pesticide contamination in aquaculture and its impact on fishery products. We conducted an assessment of 300 samples collected from nine regions in South Korea, including various types of seafood, such as freshwater fish, marine fish, crustaceans, and shellfish. Pesticide residues in seafood were analyzed using GC–MS/MS after sample preparation using a modified QuEChERS method, revealing the presence of eight pesticides (4,4′-DDE, 4,4′-DDT, boscalid, isoprothiolane, oxadiazon, pendimethalin, thifluzamide, and trifluralin) across seven fish species (carp, far eastern catfish, crucian carp, eel, Chinese muddy loach, mirror carp, and sea bass). Following the grouping of DDE with DDT, a risk assessment of fishery products was conducted. After the estimated daily intake (EDI) of fish was calculated and compared with the acceptable daily intake (ADI), the health risk index (HI, %ADI) of the detected pesticides was evaluated and found to be 1.07% or lower. The results suggest that the consumption of domestically farmed fish products in South Korea poses minimal health risks associated with pesticide residues.

The brown alga Saccharina japonica is widely consumed in Asian countries, and post-harvest drying methods such as sun drying and oven drying are commonly used to extend the shelf life of S. japonica. Thus, the present study analyzed the ethanol extract and organic solvent fractions of S. japonica to examine the effects of UVA and heating on certain bioactive compounds (fucoxanthin, phlorotannin compounds, and total antioxidants) during the drying process. The fucoxanthin contents in the ethanol extract and different solvent fractions significantly decreased in response to UVA. However, fucoxanthin in the ethanol extract and other fractions showed resistance to thermal treatment. It is noteworthy that the total phlorotannin content (TPC) in the ethanol extract and all fractions showed an approximately 2.5-fold increase upon UVA radiation. The TPC also increased in all samples exposed to high temperatures, except for those in the chloroform fraction. The total antioxidant capacity (TAC) also exhibited significant increases in a pattern similar to the TPC. The findings demonstrate that UVA exposure and heating stimulated the degradation of fucoxanthin while it increased the TPC and TAC in the extract and fractions of S. japonica.

Background/Objectives: Seaweeds have recently gained global attention as sustainable and health-promoting food sources. However, seaweeds contain iodine. While iodine is a beneficial micronutrient, its excessive intake can pose health risks. Therefore, ensuring iodine safety has emerged as a critical priority. The present study aims to determine the total iodine content in five major edible seaweeds, namely laver (Porphyra spp.), sea mustard (Undaria pinnatifida), sea tangle (Saccharina japonica), green laver (Enteromorpha spp.), and hijiki (Hizikia fusiforme), collected from 12 coastal regions in South Korea during 2020–2024. Methods: A total of 348 samples were analyzed using inductively coupled plasma mass spectrometry following microwave-assisted digestion. A risk assessment was performed based on the estimated daily intake and hazard index (HI) using both the Korean Ministry of Food and Drug Safety (MFDS), EFSA (European Food Safety Authority), and the Joint FAO/WHO Expert Committee on Food Additives (JECFA) reference values. Results: The iodine content varied widely among the different species, with sea tangles exhibiting the highest levels (mean 2432 mg/kg dry weight). The HI values were all below 1.0, based on MFDS standards, indicating a low potential health risk. However, sea tangle exhibited values exceeding 1.0 based on the EFSA and JECFA standards. Conclusions: These findings highlight the need for species-specific iodine intake guidelines and safety regulations to ensure consumer protection and facilitate global seaweed trade. The present study provides a scientific basis for balancing the nutritional benefits of seaweed with the potential risks of overconsumption, contributing to the development of national dietary guidelines and providing evidence-based data for navigating international regulatory landscapes.

Abalone (Haliotis discus hannai) is a widely consumed seafood in Asian countries. Rich in protein, abalone is consumed for refreshment, pregnancy care, and vitality. Although many studies have found that abalone protein has beneficial effects, the efficiency of the protein extraction method for abalone has rarely been studied. Therefore, this study aimed to examine the effects of various factors of abalone protein extraction, including extraction buffer, sonication, salt (NaCl) concentration, surfactant, and heating. Phosphate buffer showed higher protein yield compared with Tris-HCl buffer. In addition, the highest protein yield for each factor was observed at 60 s of sonication (84.44 µg/mg dw), 0.6 M NaCl (141.9 µg/mg dw), and 16 mM sodium dodecyl sulfate (SDS) (253.15 µg/mg dw). However, a combined effect was not observed. Lower protein extraction efficiency was observed for sous vide-cooked abalone. The electrophoresis assay revealed myofibrillar proteins, including paramyosin, actin, and tropomyosin. Overall, our results demonstrate that various extract conditions affect the protein extraction of abalone.