Methodology was developed for the extraction of surface components of sweetpotato [Ipomoea batatas (L.) Lam.] storage roots. Surface components of storage roots were quantitatively extracted with methylene chloride using 8-minute ultrasonication. After removal of the solvent, the extract was treated with 3 Tri Sil-Z:1 trimethylsilylimidazol (v/v) to convert components with hydroxyl moieties to silyl ethers and then separated on a SE-54 fused silica capillary column. Distinctly different gas chromatography profiles were found between lines displaying moderate levels of resistance (`Resisto', `Regal', `Jewel') to the sweetpotato weevil [Cylas formicarius elgantulus (summers)] and weevil-susceptible lines (`Centennial', SC 1149-19, W-115), indicating a possible role of surface components in insect response. Chromatographic fractionation techniques were developed for separation of major components or groups of components. The results will allow subsequent bioassaying for the presence of an ovipositional stimulant(s) and other weevil behavior-modulating compounds and their chemical characterization.
Ki-Cheol Son, Ray F. Severson, Richard F. Arrendale, and Stanley J. Kays
Sin-Ae Park, A-Young Lee, Hee-Geun Park, Ki-Cheol Son, Dae-Sik Kim, and Wang-Lok Lee
The objective of this study was to investigate the effects of a gardening intervention as a physical activity in women aged over 70 years. Twenty-one women aged over 70 years were recruited from the community in Seoul, South Korea. Eleven subjects at a senior community center participated in a 15-session gardening program (twice a week, average 50 minutes per session) from Sept. to Nov. 2015. The rest of the subjects who were recruited from another senior community center acted as the control group. Blood lipid profiles, blood pressure, inflammation in peripheral-blood mononuclear cells (PBMC), and oxidative stress were assessed by a blood test before and after the 15-session gardening intervention. The results showed that the subjects in the gardening intervention as a low- to moderate-physical activity had a significant improvement in their high-density lipoprotein (HDL) level, systolic and diastolic blood pressures, and the variables related to immunity such as tumor necrosis factor-α (TNF-α) for inflammation in blood and receptor for advanced glycation end products (RAGE) expression for oxidative stress. The results of this study suggested that the 15-session gardening intervention as a low- to moderate-physical activity led to positive effects on the blood lipid profiles, blood pressure, level of inflammatory markers in blood, and oxidative stress of women aged over 70 years.
Kwang Jin Kim, Mi Jung Kil, Jeong Seob Song, Eun Ha Yoo, Ki-Cheol Son, and Stanley J. Kays
The contribution of aerial plant parts versus the root zone to the removal of volatile formaldehyde by potted Fatsia japonica Decne. & Planch. and Ficus benjamina L. plants was assessed during the day and night. The removal capacity of the entire plant, aerial plant parts, and root zone was determined by exposing the relevant parts to gaseous formaldehyde (2 μL·L−1) in airtight chambers (1.0 m3) constructed of inert materials. The rate of formaldehyde removal was initially rapid but decreased as the internal concentration diminished in the chamber. To compare the removal efficiency between species and plant parts, the time interval required to reach 50% of the initial concentration was determined (96 and 123 min for entire plants of F. japonica and F. benjamina, respectively). In both species, the aerial plant parts reduced the formaldehyde concentration during the day but removed little during the night. However, the root zone eliminated a substantial amount of formaldehyde during the day and night. The ratio of formaldehyde removal by aerial plant parts versus the root zone was similar for both species, at ≈1:1 during the day and 1:11 at night. The effectiveness of the root zone in formaldehyde removal was due primarily to microorganisms and roots (≈90%); only about 10% was due to adsorption by the growing medium. The results indicate that the root zone is a major contributor to the removal of formaldehyde. A better understanding of formaldehyde metabolism by root zone microflora should facilitate maximizing the phytoremediation efficiency of indoor plants.