Migration of substances from food contact plastic materials into foodstuff and their implications for human exposure.

The safety of food contact plastic materials, including PP, PE, PET, PCT, PLA, PBT and cross-linked polyester, was assessed with regard to migrated substances. The migrated concentrations of overall migrants (OMs), terephthalic acid, acetaldehyde, 1,4-butanediol and lead, were determined according to the standards and specifications for utensils, containers and packages in Korea. Food simulants of 4% acetic acid, water and n-heptane were used for the analysis of the substances.

Reduction of total, organic, and inorganic arsenic content in (Hijiki).

This study aimed to evaluate the reduction of total, organic, and inorganic arsenic content in (hijiki). Initially, the six most common arsenic compounds in hijiki and its organs were evaluated, among which only arsenate and arsenobetaine were detected. Thereafter, the entire plant, including the stalk and leaves, was treated with heat and NaCl solution, individually and in combination.

Exposure assessment to paralytic shellfish toxins through the shellfish consumption in Korea.

Paralytic shellfish poisoning is caused by saxitoxin and its analogues. The paralytic shellfish toxins (PSTs) are produced by marine dinoflagellates and can be accumulated in filter feeding shellfish, such as mussel, clam, oyster and ark shell. The worldwide regulatory limits for PSTs in shellfish are set at 80 μg STX eq.

Identification and structure elucidation of a p-phenoxybenzaldehyde in bamboo shoots by HPLC-ESI/MS/MS and NMR.

In this study, a derivative of p-phenoxybenzaldehyde in bamboo shoots was investigated. Bamboo shoots were ground and extracted with water, and an aqueous suspension was purified by SPE using Oasis HLB cartridges. After the SPE procedure, the analytes were analyzed by HPLC with refractive index detection (HPLC-RI).

Novel anticancer agent, benzyldihydroxyoctenone, isolated from Streptomyces sp. causes G1 cell cycle arrest and induces apoptosis of HeLa cells.

In the course of screening for anticancer agents, a novel active compound, F3-2-5, was isolated from culture broth of Streptomyces sp., KACC91015. Its structure was identified using nuclear magnetic resonance, mass spectrometry, and molecular modeling experiments, and confirmed by total synthesis.

Conformational analysis in solution of gastrin releasing peptide.

Gastrin releasing peptide (GRP) is the first peptide isolated from porcine gastric and intestinal tissues and is homologous to the carboxyl terminus of bombesin (Bn) isolated from the skin of the frog Bombina bombina. It is a member of the Bn-like peptides, which are important in numerous biological and pathological processes. The Bn-like peptides show high sequence homology in their C-terminal regions, but they have different selectivity for their receptors.

A novel antiproliferative agent, phenylpyridineylbutenol, isolated from Streptomyces sp.

A novel compound showing antiproliferative effect was isolated from Streptomyces sp. Its structure was determined based on the interpretation of the NMR spectra, and its conformation was elucidated using molecular modeling and 2D NOESY. It was determined to be (E)-4-phenyl-3-(pyridine-2-yl)but-2-en-1-ol.

Conformational analysis in solution of protein kinase C betaII V5-1 peptide.

One of protein kinase C (PKC) isozymes, PKC beta binds to receptor for activated C kinase 1 (RACK1), and their complex is suggested to be translocated to melanosomes. The binding site of PKC beta for RACK1 is considered one of its catalytic domains, V5 domain which consists of three motifs such as V5-1, V5-2, and V5-3. Among these, V5-1 region, extreme C-terminal residues of PKC beta showed the highest RACK1-binding affinity.

Structure determination of a sildenafil analogue contained in commercial herb drinks.

It was found from HPLC analysis that a commercial herb drink contains a putative sildenafil analog. In order to identify the sildenafil-like compound, separation and purification were carried out. The structure determination was performed based on routine 1D and 2D NMR experiments.