• Bulletin of the Korean Chemical Society
• /
• v.33 no.12
• /
• pp.3971-3976
• /
• 2012

A simple method was developed for the analysis of seven stilbene-type fluorescent whitening agents (FWAs) in paper materials by ion-pair reversed-phase high-performance liquid chromatography with fluorescence detection. These stilbene-type FWAs included two disulfonate, two tetrasulfonate, and three hexasulfonate compounds. After optimization of chromatographic conditions, the FWAs were satisfactorily separated using a reversed-phase column (RP-18) with the following isocratic mobile phase: methanol-water (60:40) containing 17.5 mM TBABr and 10 mM citrate buffer (pH = 7.0). The calibration plot was linear in the range from 5 to 500 ng/mL for two disulfo-FWAs and from 1 to 500 ng/mL for the other five FWAs. Precision levels of the calibration curve as indicated by RSD of response factors were 1.2 and 8.1%. Limits of quantitation (LOQ) ranged from 1.2 to 11 ng/mL.

• Natural Product Sciences
• /
• v.28 no.3
• /
• pp.93-104
• /
• 2022

Methicillin-resistant Staphylococcus aureus (MRSA) is a serious threat to the global healthcare system. Ineffective and resistance to antibiotic treatments have increased morbidity and mortality rates worldwide. New and effective antibiotics are needed to combat against bacterial resistance. Endophytic fungi are crucial reservoirs of novel bioactive metabolites. In particular, the secondary metabolites show promising therapeutic potential, notably, antibacterial. This review discussed the emerging potential of endophytic fungi as anti-MRSA agents. The ecological sources of endophytic fungi were discussed with the synthesis of bioactive metabolites. The mode of antibacterial actions was elucidated to give a better understanding of the mechanisms involved. This review may serve as an important reference for future discovery and developments of anti-MRSA agents from endophytic fungi.

• Elastomers and Composites
• /
• v.26 no.2
• /
• pp.115-122
• /
• 1991

Polychloroprene rubber was moisture-cured after treating them with silane coupling agents such as 3-mercaptopropyltrimethoxysilane(MPS), 3-methacryloxypropyltrimethoxysilane(MAS) and vinyltriethoxysilane(VES), especially MPS. The cure reaction is composed of two steps. The first is the reaction between chlorine atoms of CR and silane coupling agents. The second is the formation of cross-links which are siloxane linkage. The linkage is formed by the condensation of silanol groups which are produced by the hydrolysis of alkoxysilyl groups. The first reaction was kinetically studied and the reactivity of CR to silane coupling agents was determined in previous literature. Crosslinking density and mechanical properties of the moisture-cured elastomer filled with silica or non-filled were studied and the feasibility of this cure system was discussed.

• Bulletin of the Korean Chemical Society
• /
• v.31 no.3
• /
• pp.749-752
• /
• 2010

• Polymer Science and Technology
• /
• v.2 no.1
• /
• pp.23-34
• /
• 1991

• Bulletin of the Korean Chemical Society
• /
• v.23 no.12
• /
• pp.1695-1696
• /
• 2002

• Bulletin of the Korean Chemical Society
• /
• v.28 no.5
• /
• pp.863-866
• /
• 2007

• Bulletin of the Korean Chemical Society
• /
• v.21 no.11
• /
• pp.1162-1164
• /
• 2000

• Bulletin of the Korean Chemical Society
• /
• v.15 no.3
• /
• pp.177-179
• /
• 1994

• Journal of the Korean Applied Science and Technology
• /
• v.21 no.4
• /
• pp.306-312
• /
• 2004

An acid cleaning agent (AACA) for aluminum was prepared by blending of sorbitol, n-octanoic acid, MJU-100A, Tetronix T-701, PPA-23, C8-83 and phosphoric acid. With the prepared AACA, degreasing, foam height, etching and derusting tests were carried out. As a result, AACA-4 and AACA-7 showed better cleaning ability than commercial acid cleaning agents.