• Korean Journal of Plant Resources
• /
• v.25 no.4
• /
• pp.490-497
• /
• 2012

Phylogenetic analyses were conducted to evaluate relationships of 5 taxa of Korean Hydrocotyle, H. spp. found in the Ulleung island including one outgroup (Centella asiatica). The molecular phylogenetic methods based on nuclear ribosomal DNA ITS region and cpDNA trnH-psbA region. Centella asiatica was used outgroup for analysis. As the result, genus Korean Hydrocotyle were grouped by 94% bootstrap value. Korean Hydrocotyle was grouped by four clades; Clade I-H. maritima, H. sibthorpides and H. yabei clade Clade II-H. nepalensis clade clade III-H. ramiflora clade clade IV-H. spp. clade. H. maritima, H. sibthorpides and H. yabei was not distinguished, seperately. H. spp. was distinctly distinguished other Korean Hydrocotyle.

• Journal of Mushroom
• /
• v.2 no.4
• /
• pp.184-191
• /
• 2004

Mutual growth limitation was observation when the two antagonistic fungi was come in contact with each other. Brown line was formed 2day after contact with Trichoderma spp., and then, green spores formed overnight. The laccase activity of L. edodes was stimulated when this fungus wsa co-incubated with Trichoderma spp. for a few days in liquid media. In sawdust-rice bran nixtures, outstanding broun line developed when the two antagonistic fungi co-cultured. The pH of the substrates changed from 5.5 to 4.5 after overgrowth, suggesting a difference in the degradation ability and the preference of the two fungi for the lignocellulose material.

• Food Science of Animal Resources
• /
• v.29 no.6
• /
• pp.702-708
• /
• 2009

We investigated biofilm formation in various media, growth in low pH, and the hemolytic activity of 14 strains of Cronobacter spp. (Enterobacter sakazakii) isolated from a variety of foods including powdered infant formula (n=75), infant cereal (n=100), honey (n=30), and other infant foods (n=100) in Korea. The Cronobacter spp. adhered and formed biofilms on polyethylene, and a greater extent of biofilm was observed in nutrient-rich media. No clear difference in biofilm-forming ability was noted among the media constituents and the pattern of biofilm formation was strain-dependent. Seven strains out of 14 strains (50%) grew at pH 4.1, indicating that the acid resistance of these Cronobacter spp. isolated in Korea was relatively low. Hemolytic activity was not observed in any of the strains. This study provides basic information for the physiological and biochemical characteristics of Cronobacter spp. isolated from a variety of infant foods in Korea.

• Journal of Food Hygiene and Safety
• /
• v.22 no.1
• /
• pp.37-44
• /
• 2007

The approval of use of certain food-grade phosphates as food additives in a wide variety of meat products greatly stimulated research on the applications of phosphates in foods. Although phosphates have never been classified as antimicrobial agents, a number of investigators have reported that phosphates have antimicrobial activities. Phytic acid is a natural plant inositol hexaphosphate constituting 1-5% of most cereals, nuts, legumes, oil seeds, pollen, and spores. In this study, we investigated antibacterial activities of sodium phytate(SPT), sodium pyrophosphate (SPP), sodium tripolyphosphate (STPP) on Escherichia coli O157:H7 on tryptic soy broth and in beef, pork and chicken. In tryptic soy broth, SPT, SPP and STPP at the concentrations of 0.05, 0.1, and 0.5% effectively inhibited the growth of Escherichia coli O157:H7 in a concentration-dependent manner. The bactericidal activity of SPT was the stronger than that of SPP or STPP at the same concentrations. In addition, the antibacterial effects of SPT, SPP and STPP at the concentrations of 0.05, 0.1, 0.3, and 0.5% on Escherichia coli O157:H7 were also investigated in raw or cooked meats including beef, pork and chicken. SPT, SPP and STPP significantly inhibited the bacterial growth in a dose-dependant manner (p<0.05). The bactericidal effect of SPT was stronger than that of SPP or STPP. The addition of SPT, SPP and STPP in meats increased meat pHs. SPP and STPP also increased the levels of soluble orthophosphate in meats but STP did not. These results indicate that SPT is very effective for inhibition of bacterial growth and that can be used as a muscle food additive for increasing functions of meats.

• Korean Journal of Veterinary Service
• /
• v.32 no.1
• /
• pp.33-41
• /
• 2009

In order to develop probiotic strain for pigs, Lactobacillus spp. (527 isolates), Streptococcus spp. (95 isolates) and Bifidobacterium spp. (25 isolates) were isolated from the feces of 35 pigs. These isolates were tested through in vitro experiment such as acid tolerance at pH 2.0 (Lactobacillus spp. and Streptococcus spp.) or pH 3.0 (Bifidobacterium spp.), bile tolerance in MRS broth containing 0.3% (w/v) Oxgall, heat resistance at $70^{\circ}C$ and $80^{\circ}C$ for 5 min, antibiotic resistance, antimicrobial activity against pathogenic bacteria and Caco-2 cell adherence assay. Finally ten most superior strain (5 Lactobacillus spp. strain, 3 Bifidobacterium spp. strain and 2 Streptococcus spp. strain) were selected as potential candidate for probiotic use in pig industry. It could be used as an alternative to antibiotics in feed additives.

• Asian-Australasian Journal of Animal Sciences
• /
• v.8 no.3
• /
• pp.267-273
• /
• 1995

The differences in rumen particle pool size, passage rate and rumen degradability in sheep receiving three varieties of orchardgrass hay harvested at pre-heading (H1), early-bloom (H2) and late-bloom (H3) were investigated using four ruminal-cannulated wethers (68 kg) fed 1,300 g of the hay once a day. Representative samples of whole rumen contents were collected at different times after feeding and the quantities of rumen particle pools [large particle pool (LPP), retained on a $1,180{\mu}m$ sieve; small particle pool (SPP), retained on a 47 but passed a $1,180{\mu}m$ sieve; and soluble fraction (SOL), passed a $47{\mu}m$ sieve (SOL)] were determined by a wet-sieving technique. The fullowing results were obtained: 1) The dry weight of whole rumen contents were significantly lower (p < 0.05) for HI than for H2 or H3. The reduction rate of whole rumen contents was slightly but significantly greater for HI that, the other hay varieties. 2) The LPP disappearance rates were 26.2, 25.3 and 21.7 g DM/h for H1, H2 and H3, respectively, and no statistical differences were found among the hay varieties. Appreciable changes were not observed with SPP and SOL throughout measurements for all hay varieties; however the SPP was markedly greater (p <0.05) for H2 and ill than for HI, while SOL did not differ among hay varieties. 3) The SPP passage rate (g DM/h) and effective rumen degradability (%) for HI, H2 and ill were, respectively, 9.7, 56.6; 16.9, 42.3; and 18.0, 28.9. The ruminal tum-over rate for SPP appeared to be higher for HI than for the other hay varieties.

• Journal of Food Hygiene and Safety
• /
• v.37 no.3
• /
• pp.173-180
• /
• 2022

There are a number of methods to evaluate the quality of squid. However, when purchasing the fish, consumers and retails rely only on the sensory test and flavor in the field. Therefore, this study was aimed to prove relationship between scientific indicator and sensory test. Total viable cell count (TVC), viable cell count of Pseudomonas spp., pH and volatile basic nitrogen (VBN) were selected as scientific indicators and mesured during the storage of squid at different temperature. The squid was storaged at 3 different temperature (5℃, 15℃, 20℃). Off flavor determination time was measured by R-index, and kinetic modeling was conducted. Activation energies of off-flavor determination time, TVC, Pseudomonas spp, VBN, and pH were 51.210 kJ/mol, 42.88 kJ/mol, 50.283 kJ/mol, 72.594 kJ/mol and 41.99 kJ/mol respectively. Activation energy of off-flavor determination time was approximated to viable cell count of Pseudomonas spp., TVC, pH and VBN as an order. Especially, viable cell count of Pseudomonas spp. had best match of the activation energy. Therefore, it was judged that indicator of off-flavor determine time was viable cell count of Pseudomonas spp..

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.8 no.1
• /
• pp.54-57
• /
• 2003

H$_2$-producing bacteria were isolated from anaerobic granular sludge. Out of 72 colonies (36 grown under aerobic conditions and 36 under anaerobic conditions) arbitrarily chosen from the agar plate cultures of a Suspended sludge, 34 colonies (15 under aerobic conditions and 19 under anaerobic conditions) produced H2 under anaerobic conditions. Based on various biochemical tests and microscopic observations, they were classified into 13 groups and tentatively identified as follows: From aerobic isolates, Aeromonar spp. (7 strains), Pseudomonas spp. (3 strains), and Vibrio spp. (5 strains); from anaerobic isolates, Actinomyces spp. (11 Strains), Clostridium 5pp. (7 strains). and Porphyromonas sp. When glucose was used as the carbon substrate, all isolates showed a similar cell density and a H$_2$ production yield in the batch cultivations after 12 h (2.24-2.74 OD at 600 nm and 1.02-1.22 mol H$_2$/mol glucose, respectively). The major fermentation by-products were ethanol and acetate for the aerobic isolates, and ethanol, acetate and propionate for the anaerobic isolates. This study demonstrated that several H$_2$ producers in an anaerobic granular sludge exist En large proportions and their performance in terms of H$_2$ production is quite similar.

• The Korean Journal of Pesticide Science
• /
• v.2 no.2
• /
• pp.83-89
• /
• 1998

The occurrence of postharvest disease of apple was surveyed from 1995 to 1997 in the major apple-producing area in Korea. Ten genera including Alternaria spp., Botryosphaeria dothidea, Botrytis cinerea, Fusarium spp., and Penicillium spp. were isolated from the decayed apple fruits. Of these, B. cinerea, Penicillium spp. and Fusarium spp. were frequently isolated and were highly pathogenic to apple fruits. Optimum temperature of mycelial growth for Penicillium spp. ranged from 10 to $30^{\circ}C$ and that of mycelial growth for B. cinerea and Alternaria spp. ranged from 5 to $30^{\circ}C$. Optimum temperature of sporulation of Penicillium spp. and Alternaria spp. ranged $15{\sim}25^{\circ}C$ and $10{\sim}20^{\circ}C$, respectively. Occurrence of postharvest disease of apple increased in neglecting selection of wounded fruits before storing apples. Most of these fungi causing postharvest diseases such as Penicillium spp, Botrytis cinerea and Alternaria spp. were isolated from healthy fruits sampled at apple orchard. These results suggested that posthavest diseases of apple were originated from apple fruits contaminated from apple orchard and occurred during storage. In addition, five fungicides including prochloraz EC, fenari EC, captan WP, benomyl WP and folpet WP suppressed posthavest diseases when they sprayed on apple fruits at 30 days before harvesting.

• Food Science of Animal Resources
• /
• v.24 no.1
• /
• pp.92-96
• /
• 2004

pH, Campylobacter spp., Salmonella spp. and Escherichia coli of under-utilized broiler viscera silage added with table sugar during storage at 25$^{\circ}C$ were investigated. pH of silage with 0 and 1 %(w/w) table sugar increased continuously after day 2, but that of 3, 4 and 5% remained 4.0∼4.2 after decrease from 5.2 at day 0. The Campylobacter spp. count of 0% was 8.21 at day 4, however that of 3 and 5% showed 7.56 and 7.38 logCFU/mL, respectively. The Salmonella spp. of 0% maintained 5.8∼6.8 logCFU/mL during fermentation, but that of 3 and 5% was not detected after day 4. The initial E. coli count of silage without table sugar was 5.8 log CFU/mL, but reduced to 4.1 log CFU/mL at day 2, and maintained at the level between 4.0 and 5.0 log CFU/mL, thereafter. However, E. coli was not detected in the silage with 3 and 5% table sugar after day 2. The counts of Campylobacter spp., Salmonella spp. and Escherichia coli of under-utilized broiler viscera silage reduced markedly by adding table sugar. It was proved that the possibility of microbiologically safe broiler offal silage as a potential resource for animal feed materials was improved.