Kun-Ho Son

Methyl Protodioscin from the Roots of Asparagus cochinchinensis Attenuates Airway Inflammation by Inhibiting Cytokine Production.

The present study was designed to find pharmacologically active compound against airway inflammation from the roots of Asparagus cochinchinensis. The 70% ethanol extract of the roots of A. cochinchinensis (ACE) was found to inhibit IL-6 production from IL-1β-treated lung epithelial cells (A549) and the major constituent, methyl protodioscin (MP), also strongly inhibited the production of IL-6, IL-8, and tumor necrosis factor- (TNF-) α from A549 cells at 10–100 μM. This downregulating effect of proinflammatory cytokine production was found to be mediated, at least in part, via inhibition of c-Jun N-terminal kinase (JNK) and c-Jun activation pathway. When examined on an in vivo model of airway inflammation in mice, lipopolysaccharide- (LPS-) induced acute lung injury, ACE, and MP significantly inhibited cell infiltration in the bronchoalveolar lavage fluid by the oral treatment at doses of 100–400 mg/kg and 30–60 mg/kg, respectively. MP also inhibited the production of proinflammatory cytokines such as IL-6, TNF-α, and IL-1β in lung tissue. All of these findings provide scientific evidence supporting the role of A. cochinchinensis as a herbal remedy in treating airway inflammation and also suggest a therapeutic value of MP on airway inflammatory disorders.

Two new steroidal saponins from the tubers ofLiriope spicata

Two novel steroidal saponins designated as spicatosidesA(1) andB(2) were isolated from the tubers ofLiriope spicata and their structures were clucidated as 25(S)-ruscogenin-1-O-β-D-glucopyranosyl (1→2)-[β-D-xylopyranosyl (1→3)]-β-D-fucopyranoside (1) and 26-O-β-D-glucopyranosyl 25(S)-22-O-methyl-furost-5-en-1β, 3β, 26-triol 1-O-β-D-glucopyranosyl (1→2)-[β-D-xylopyranosyl (1→3)]-β-D-fucopyranoside (2), respectively.

Corrosion Behavior of 316L Stainless Steel in Supercritical Water Environment

There is a need to destroy both military and civilian hazardous waste and urgency, mandated by public concern over traditional waste handling methodologies, to safe and efficient alternative technologies. One very effective process for the destruction of such waste is supercritical water oxidation (SCWO). Nevertheless, corrosion of the materials of fabrication is a serious concern. This work intends to obtain the fundamental data for developing the corrosion resistant steel for the construction of SCWO system. The effects of various factors on the corrosion resistance of flat, welded, and U-bend 316L stainless steels in Trimsol solution were studied. Corroded product on surface was composed of multi-layer with oxides and salts, and dealloying was observed. Major corrosion phenomena of 316L stainless steel under SCWO condition were intergranular corrosion, pitting corrosion, SCC, and erosion corrosion. This work focused on the elucidation of corrosion mechanism of 316L stainless steel in SCWO environment.