Weon-Sun Shin

Fructus panax ginseng extract promotes hair regeneration in C57BL/6 mice

ETHNOPHARMACOLOGICAL RELEVANCE Radix panax ginseng (Panax ginseng C.A. Meyer, Araliaceae, RPG) has been documented to possess hair growth activity and widely used to treat alopecia, while no report has been issued to date on the effect of Fructus panax ginseng (FPG) on hair regeneration. MATERIALS AND METHODS To investigate the effects of FPG extract on the proliferation of human hair dermal papilla cells (DPCs) and on the promotion of hair regeneration in C57BL6 mice, cell proliferation was evaluated in cultured DPC by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and measured the expressions of Bcl-2 and Bax by immunoblot assay. We also compared the effects of topical FPG extract (1 and 10 mg/ml, 100 μl/d) with the effects of minoxidil as a positive control (5%, 100 μl/d) or vehicle control (30% ethanol) on the depilation-induced hair cycling in 7 week-old-C57BL/6 mice. RESULTS FPG extract significantly increased the proliferation of DPCs in dose and time dependent manners (P<0.05, P<0.01 and P<0.001). FPG extract also enhanced Bcl-2 expression and decreased Bax expression compared with control (P<0.01). Moreover, significant elongations of anagen phase during hair cycle after application of FPG were evaluated by photographical and histological observations. CONCLUSIONS FPG extract improves the cell proliferation of human DPCs through anti apoptotic activation. Topical administration of FPG extract might have hair regeneration activity for the treatment of hair loss.

Characterisation of bovine serum albumin-fucoidan conjugates prepared via the Maillard reaction

Bovine serum albumin (BSA)-fucoidan conjugates were prepared by the Maillard reaction (60 °C and 79% relative humidity for 96 h), and were then identified by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and size-exclusion chromatography (SEC). Molecular characteristics of the BSA-fucoidan conjugates were investigated, using atomic force microscopy (AFM), dynamic light scattering (DLS), fluorescence spectroscopy, and circular dichroism spectroscopy. SDS-PAGE patterns provided evidence for the covalent bonding between BSA and fucoidan. SEC profiles showed that about 1.5-2.0 mol of fucoidan were covalently linked to 1 mol of BSA, resulting in high-molecular-weight compositions (conjugates). AFM images and DLS results indicated that most particles in the conjugates were nano-structured and more spherical than those of a regular BSA-fucoidan mixture. The fluorescence intensity and maximum emission wavelength of the conjugates together revealed that the BSA molecules had converted from an ordered conformation into a partially folded molten globule state.

Assessment of Microbiological Quality for Raw Materials and Cooked Foods in Elementary School Food Establishment

This study was conducted to assess the microbiological quality of raw and cooked foods served in the elementary school food service. Raw and cooked food samples were collected from 11 selected elementary schools in both June to July and September to October of 2005. Petrifilm plates were used to determine (in duplicate) total aerobic colony counts (PAC), Enterobacteriaceae (PE), coliform counts (PCC), and E. coli counts (PEC). Heavy contamination of Enterobacteriaceae (from 0.08 to 7.40 log CFU/g) and total coliform (0.50 to 6.52 log CFU/g) were observed in raw materials and cooked foods. Escherichia coli (E. coli) were detected in the sample of currant tomato (3.70 log CFU/g), sesame leaf (3.59 log CFU/g), dropwort (0.20 log CFU/g), crown daisy (3.15 log CFU/g), parsley (3.00 log CFU/g), peeled green onion (1.74 log CFU/g), frozen pork (0.65 log CFU/g), frozen beef (0.20 or 1.50 log CFU/g), chicken (1.78 log CFU/g), and young radish leaf seasoned with soybean paste (1.24 log CFU/g). Multiplex PCR system was used to determine the food-borne pathogens: Salmonella spp., Bacillus cereus (B. cereus), E. coli O157:H7, Staphylococcus aureus, Listeria monocytogenes (L. monocytogenes), Vibrio parahaemolyticus, Campylobacter jejuni (C. jejuni), Shigella spp., B. cereus was detected in 19 samples of raw materials and 8 samples of cooked foods. With regard to quantitative analysis, B. cereus counts exceeded 5.46, 3.48 and 1.79 log CFU/g in sesame leaf, peeled green onion and seasoned mungbean jelly, respectively. E. coli O157:H7 was detected on 2 samples of frozen beefs, and its biochemical characteristics of one beef sample was confirmed with API 20E kit (93.7%). L. monocytogenes was detected in fried rice paper dumpling, but the presumptive colonies were not detected onto the conventional plate. C. jejuni was detected in peeled & washed onion.

Differences in eating behaviors and masticatory performances by gender and obesity status

This study aimed to determine whether there might be differences in masticatory performance and eating behaviors by gender and obesity status. Forty eight (24 males; 24 females) non-obese and pre-obese young adults were matched for age, gender, and dental health. Eating behaviors were assessed using the Three-Factor Eating Questionnaire (TFEQ), and chewing performance while eating 152g of boiled rice was measured using electromyography (EMG). Compared with non-obese participants, pre-obese participants had significantly higher levels of disinhibition according to the TFEQ (P<0.05 for males; P<0.01 for females). Microstructures of chewing performance were significantly different by gender but not by obesity status. Males had a greater bite size (P<0.05), greater chewing power (P<0.001) and a faster eating rate (P<0.05) than females. Females habitually chewed more (P<0.05) and had a longer meal duration (P<0.01) than males. Eating rate was positively associated with disinhibition (r=0.490, P<0.05) score in males. Bite size (r=-0.449, P<0.05 for non-obese) and chewing power (r=-0.581, P<0.01 for non-obese and r=-0.446, P<0.05 for pre-obese) were negatively associated with disinhibition score. Results suggest that the effects of gender and, in part, obesity on eating responses may be explained as chewing performance. Therefore, gender-specific interventions and counseling aimed at slowing the rate of ingestion could be promising behavioral treatments for obese persons.

Functional improvements in bovine serum albumin-fucoidan conjugate through the Maillard reaction.

The solubility, thermal stability, surface activity and emulsifying properties of native bovine serum albumin (BSA), heat-treated BSA, a BSA-fucoidan mixture, and a BSA-fucoidan conjugate were assessed. Covalent linkage of BSA with fucoidan resulted in significantly (p < 0.05) high solubility after heating at 90 °C for 15 min, particularly at pH 5. The BSA-fucoidan conjugate had a high melting temperature (97.09 ± 1.45 °C), as found by differential scanning calorimetry, indicating strong heat stability and high resistance to denaturation. Although the attachment of fucoidan, a non-surface-active hydrophilic polysaccharide, gave no change in the surface activity, the emulsifying activity and the emulsion stability of the conjugate at pH 5 were superior to those of native BSA, heat-treated BSA, and the BSA-fucoidan mixture. Conclusively, fucoidan attachment enhanced the solubility, thermal stability and emulsifying properties of the protein molecules with negative charge distribution and steric stabilization.

Optimization of rapid detection of Escherichia coli O157:H7 and Listeria monocytogenes by PCR and application to field test.

For rapid detection of Escherichia coli O157:H7 and Listeria monocytogenes, simple methods for sample preparation and PCR were established and applied to a field test. To improve specificity, primer sets LP43-LP44 and C(+)-D(-) were selected for E. coli O157:H7 and L. monocytogenes, respectively. Through centrifugation and partial heat treatment after enrichment, E. coli O157:H7 and L. monocytogenes were detected at 1 initial CFU without genomic DNA extraction in the culture and with artificially inoculated food samples including milk, chicken, ham, and pork. Based on the optimized PCR method, a feasibility test was carried out using randomly collected field samples. To remove false positives and false negatives, a PCR method using several primer sets, including the optimized primer set, and a standard culture method were used. With the PCR detection and standard culture methods, two pork samples were positive for L. monocytogenes after enrichment, indications that the PCR assay could be effectively used for rapid, sensitive, and species-specific detection of foodborne pathogens.

Establishment of Quantitative Analysis Method for Genetically Modified Maize Using a Reference Plasmid and Novel Primers

For the quantitative analysis of genetically modified (GM) maize in processed foods, primer sets and probes based on the 35S promoter (p35S), nopaline synthase terminator (tNOS), p35S-hsp70 intron, and zSSIIb gene encoding starch synthase II for intrinsic control were designed. Polymerase chain reaction (PCR) products (80~101 bp) were specifically amplified and the primer sets targeting the smaller regions (80 or 81 bp) were more sensitive than those targeting the larger regions (94 or 101 bp). Particularly, the primer set 35F1-R1 for p35S targeting 81 bp of sequence was even more sensitive than that targeting 101 bp of sequence by a 3-log scale. The target DNA fragments were also specifically amplified from all GM labeled food samples except for one item we tested when 35F1-R1 primer set was applied. A reference plasmid pGMmaize (3 kb) including the smaller PCR products for p35S, tNOS, p35S-hsp70 intron, and the zSSIIb gene was constructed for real-time PCR (RT-PCR). The linearity of standard curves was confirmed by using diluents ranging from 2×101~105 copies of pGMmaize and the R2 values ranged from 0.999~1.000. In the RT-PCR, the detection limit using the novel primer/probe sets was 5 pg of genomic DNA from MON810 line indicating that the primer sets targeting the smaller regions (80 or 81 bp) could be used for highly sensitive detection of foreign DNA fragments from GM maize in processed foods.

Roles of chondroitin sulfate in oil-in-water emulsions formulated using bovine serum albumin

Chondroitin sulfate (CS) effects on phase stability and actions in bovine serum albumin (BSA)-stabilized emulsions at different pH values were studied. Emulsion activity and stability were evaluated at CS concentrations ranging from 0 to 0.1% (w/w). BSA-CS emulsions showed unique behaviors under different pH values. CS destabilized emulsion phases drastically at pH 3.0 and gradually at pH 7.0. However, at pH 5.0, CS exerted concentration-dependent effects on emulsion stability and caused a decrease in particle size. CS is negatively charged with concentrationdependency at all pH values. However, different roles were observed when the surface charge of BSA was changed. CS formed interfacial layers via charge interactions with BSA to form complexes that sufficiently saturated the surface of oil droplets and prevented phase-separation via steric hindrance and repulsive forces, especially near the protein isoelectric point.

A Qualitative Study on Needs of Convenience Meal from the Low-income Female Elderly

This study aimed to investigate the perception, consumption, and acceptability of convenience mealsin low-income female elderly attending a lunch program at a community well fare center. Using in-depth interviews, qualitative data were collected 11 elderly females (62.5±11.2y) living in Seoul. Participants tried to eat various foods in small-portionsat home, although they ate out what they were offered. Elderly females preferred lunch box-type meals containing a bowl of rice served with toppings, gruel, or Bibimbop due to the growing unavailability of cooking or preparing a meal. Side-dish type convenience mealswere also preferred among elderly females since boiled rice can be easily prepared according to individual preferences. In addition, participants preferred healthy foods. Convenience meal planning and production, appropriate kinds of foods, cooking methods, menus, and packaging should be selected based on the elderlys functional atrophy in chewing, swallowing,digestion, and metabolic diseases. Furthermore, food preferences and comfort foods among the elderlyneed to be identified and characterized. Therefore, more information, including bite size, cutting size, and food texture, should be provided to understand and develop convenience meals for the elderly.

Growth of Clostridium perfringens spores inoculated in sous-vide processed Korean traditional Galbijjim under different storage conditions

To evaluate the microbiological safety of Korean traditional seasoned beef processed by sous-vide method, Clostridium perfringens spores were inoculated into the samples, and then germination and growth of spores were observed under different temperatures for days. Also, changes in pH, water activity, and salt contents were analyzed. As the results, there was no difference in water activity and pH of the samples during the storage at any temperature. However, salt contents of the samples significantly increased as storage time increased, and the storage temperature affected the change of salt contents. C. perfringens did not grow at 4 and 10°C for 24 days however, the bacterial growth was observed at 20°C after 2 days of storage. Based on these simulation tests, the microbiological safety of sous-vide processed galbijjim can be guaranteed at 4 and 10°C for 24 days even though the raw materials were contaminated by C. perfringens spores.