• Title/Summary/Keyword: growth pH

Search Result 6,244, Processing Time 0.037 seconds

A Study on the Effects of Probiotic Yogurt on the Microbial Quality of Fresh Chicken Meat during Cold Storage (요구르트가 신선계육의 저장기간 동안 미생물학적 품질 특성에 미치는 영향)

  • Kim, Kook-Kyung;Eom, Seok-Jin;Im, Jung-Hyun;Lee, Kyung-Min;Yoo, Seok-Jin;Kim, Hyun-Uk;Kim, Geun-Bae
    • Food Science of Animal Resources
    • /
    • v.29 no.2
    • /
    • pp.269-277
    • /
    • 2009
  • This paper reports the results of the research on the effects of probiotic yogurt on the microbiological quality, pH, and sensorial characteristics of fresh chicken meat when packed with probiotic yogurt. The chicken meat pieces were packed with yogurt and were stored at $10^{\circ}C$ for 7 days. Samples were taken after 0, 2, 4, and 7 days of storage, and were analyzed for total bacterial count, E. coli, and coliform, and for the chemical parameters, including the pH. In the control group (packed without yogurt), the Pseudomonas species predominated when the spoilage was obvious after 4-day storage at $10^{\circ}C$. The yogurt-mixed chicken meat package was found to have a significantly lower total viable count and significantly fewer coliform bacteria during storage. Furthermore, the yogurt package showed a growth-inhibiting effect on the Salmonella typhimurium, which were inoculated into the chicken meat pieces for the study. The study findings indicate that probiotic yogurt can be used in packing fresh chicken meat to decrease the population of spoilage bacteria therein and to extend its shelf life.

The Survey of Actual Using Conditions of Farm-Made Liquid Fertilizers for Cultivating Environment-friendly Agricultural Products (친환경 농산물 재배를 위한 농가 자가제조 액비 사용실태)

  • An, Nan-Hee;Jo, Young-Sang;Jo, Jeong-Rae;Kim, Yong-Ki;Lee, Yeon;Jee, Hyeong-Jin;Lee, Sang-Min;Park, Kwang-Lai;Lee, Byung-Mo
    • Korean Journal of Organic Agriculture
    • /
    • v.20 no.3
    • /
    • pp.345-356
    • /
    • 2012
  • We conducted a survey of actual using conditions of farm-made liquid fertilizers by investigating their formulation types, materials, making processes, using methods and various beneficial effects on 29 farms certified by National Agricultural Products Quality Management Service to produce environment-friendly agricultural products in 2009. Most of the materials used to make liquid fertilizers are those that can be easily obtained around the farms. Molasses or black sugar are added as an energy source of microorganism. And leaf mold, bacterial cultures supplied by agricultural extension centers of local governments, and cultures of native microorganisms were used as microbial sources for fermenting effective microorganisms. Types of the farm-made liquid fertilizers were fermented liquid fertilizers, fermented plant juices, amino acid liquid fertilizers, calcium-liquid fertilizers, and phosphoric acid liquid fertilizers. Effects of liquid fertilizers used by the farms were found to promote plant growth by supplying nutrition, to accelerate blooming and flower bud formation, to enhance the quality of agricultural products such as increase of sugar contents and improvement of storing conditions, to induce resistance against diseases and insect pests, and to cause endurance to high temperature stress. Chemical properties of the liquid fertilizers collected were analyzed. As a result, pH and EC range showed differences according to kinds of the liquid fertilizers. Amount of macro-nutrients, such as nitrogen and phosphoric acid, in most of the collected liquid fertilizers, was found to be low. Even though the liquid fertilizers were made from same materials, their contents was found to be different depending on the making process.

The Optimum Conditions for Screening of Salt Resistant Lines Through Embryo Culture in Panax ginseng C.A. Meyer (인삼 염류내성 계통의 선발을 위한 배배양 배지조건)

  • Yang, Deok-Chun;Lee, Eun-Kyung;Kwon, Woo-Saeng
    • Korean Journal of Medicinal Crop Science
    • /
    • v.11 no.2
    • /
    • pp.161-166
    • /
    • 2003
  • Korean ginseng(Panax gmseng C.A. Meyer) is very difficult to obtain stable production of qualified ginseng roots because of variable stresses in soil environments. In environment stresses, soil condition is the most important factor, among which nutrients, especially inorganic materials such as N, P, K, Ca, Mg, Fe, etc., influence greatly on the ginseng growth. However, present ginseng field soils in Korea contain so much amount of such inorganic materials that a variety of remarkable disorders were noted in many ginseng plantations, resulting in decrease of qualitative ginseng production. Therefore, it is required to search for genetic resources and genes tolerant to salt stress for the development of ginseng cultivars. Selection of stress-tolerant ginseng lines in fields is very difficult because it is almost impossible to control properly the environmental conditions of soil. On the contrary, it can be studied with ease to search for stress-tolerant ginseng lines through in vitro culture because of easy manipulation of stress conditions. Murashige & Skoog(MS) media with 2.5 folds of $KNO_3,\;NH_4NO_3,\;MgSO_4\;7H_2O,\;KH_2PO_4,\;and\;CaCl_2\;2H_2O$ was established for the selection of ginseng lines tolerant to salt stress under the embryo culture.

Studies on Cultural and Morphological Characteristics of Isolate on Ganoderma species (영지속 균주의 배양적 특성 및 형태적 특성에 관한 연구)

  • Sung, Jae-Mo;Kim, Cheon-Hwan;Moon, Hee-Woo;Kim, Soo-Ho;Lee, Hyun-Kyung
    • The Korean Journal of Mycology
    • /
    • v.24 no.1 s.76
    • /
    • pp.67-80
    • /
    • 1996
  • Eleven fruit bodies of Ganoderma sp. were collected from eight locations throughout the forest of Kangwon province and Kyunggi province in Korea. The hosts in forest were cut trunks of Quercus dentata, Q. variabilis, Prunus peria and Alnus japonica that was newly surveyed but 5 isolates were collected at the farms of Ganoderma mushroom. Most fruit bodies were formed solitarily on the cut trunks but GS-106 isolate grown in crowds on cut trunk of Alnus japonica. Optimal temperature ranges for isolates of species studied were: G. applanatum $28^{\circ}C{\sim}30^{\circ}C$, G. lucidum $28{\sim}30^{\circ}C$, G. neo-japonicum $28^{\circ}C$, and G. tsuage $26^{\circ}C$ and all the species grew slowly at the $32^{\circ}C$. Hamada medium adjusted with pH 5.4 and 6.2 is better than other media for mycelial growth. Mycelial morphological characteristics of six species were studied: G. applanatum, G. lucidum and G. neo-japonicum produced typical type of staghoru hyphae but G. oregonens and G. valeosiacum produced staghoru hyphae with a branch of grape form. Clamp connection was observed on hypha of G. applanatum, G. lucidum, G. oregonense and G. valeosiacum except G. neo-japonicum with node type. Chlamydospore was produced by G. applanatum, G. neo-japonicum. and cuticular cells were present on hyphae of G. lucidum, G. neo-japonicum, G.oregonense and G. tsugae.

  • PDF

Characterization of Mutant Strain, Lactobacillus paracasei ML-7 Isolated from Kimchi, and Its Effect on the Growth of Broiler (김치 유래의 유산균 변이주 Lactobacillus paracasei ML-7의 특성 및 육계 성장에 대한 영향)

  • Park, Keun-Tae;Oh, Mihyang;Nam, Jungok;Ji, Kibbeum;Han, Jong-Kwon
    • Korean Journal of Food Science and Technology
    • /
    • v.46 no.2
    • /
    • pp.148-152
    • /
    • 2014
  • A mutant strain of Lactobacillus paracasei (ML-7) was derived by ultraviolet irradiation of the parent L. paracasei LS-2 strain, followed by colony selection on pH 3.5 MRS agar plates, on which L. paracasei LS-2 cannot grow. The L. paracasei ML-7 mutant strain produced an increased amount of organic acids compared to the L. paracasei LS-2 parent strain. Broiler chickens were randomly fed with one of three experimental diets: a basal diet as a control, and basal diets supplemented with 0.3% of the L. paracasei LS-2 and L. paracasei ML-7 strains. When concluding the study, the final body weights of the broilers fed with the supplemented basal diets were found to be significantly higher (1.9% for LS-2 and 6.2% for ML-7) than the control broiler group. Broilers fed with basal diet supplemented with the mutant L. paracasei ML-7 strain showed increased body weight and food intake, compared to broilers fed with the basal diet with or without the parent L. paracasei LS-2 strain.

Effects of Controlled Photoperiod on Body Development in Growing Juvenile Rats

  • Lee, Seung-Hoon;Lee, Han-Ki;Shin, Jin-Hee;Hong, Yun-Kyung;Lee, Sang-Kil;Lee, Sang-Un;Suzuki, Takao;Kang, Tae-Young;Hong, Yong-Geun
    • Reproductive and Developmental Biology
    • /
    • v.34 no.2
    • /
    • pp.89-94
    • /
    • 2010
  • Melatonin is induced by light information through the retina and leads to growth factor activation. Thus, we investigated the effects of melatonin by controlling the photoperiod of growing young rats. Male Sprague-Dawley rats (n=6; 4 weeks old) were divided into two experimental groups: the L/D group (normal photoperiod; light/dark: 12/12 h; lights on at 9:00 a.m.) and the L/L group (light/light: 24 h). Rat body weight and food consumption were measured daily for 8 weeks. After 8 weeks, the rats were anesthetized with a mixture of ketamine (50 mg/kg) and xylazine (10 mg/kg) and sacrificed. Tissue was then collected for RNA isolation (from brain, heart, liver, kidney, adrenal gland, testis, tibia, hind limb muscles). Also, serum was isolated from blood using a centrifugal separation. The L/L group had significantly lower body weight than the L/D group from 4 to 6 weeks (p<0.05). The L/D group had increased tissue mass, compared with the L/L group, but the difference was not statistically significant. The L/D group had a significantly higher melatonin concentration than the L/L group between the hours of midnight and 2:00 a.m (p<0.01). These results indicate that photoperiod length may affect the secretion of melatonin from the pineal gland. Also, the reduction of nocturnal melatonin secretion may retard the development of growing young rats. In future studies, we plan to compare exogenous melatonin administration with endogenous melatonin concentration induced by photoperiod control. Moreover, we will confirm whether the effects seen in pathological animal models can be reversed by controlling the photoperiod.

Use of Recycled PET Bottle Particles as a Medium Component for Cultivation of Tomato Plug Seedlings (재활용 PET병 입자를 배지재료로 이용한 토마토 플러그묘의 재배)

  • Lee Kang Mo;Kwon Jeong Hwa;Hwang Seung Jae;Jeong Byoung Ryong
    • Journal of Bio-Environment Control
    • /
    • v.14 no.4
    • /
    • pp.302-306
    • /
    • 2005
  • This Study was Conducted in 3 glasshouse to examine the Possibility for cultivation of plug seedlings using four growing media containing recycled PET-bottle-particles (PBT) as a medium component. Plug seedlings of 'Seokwang' tomato were grown in media containing $100\%$ PBT, $100\%$ peatmoss, or $50\%$ $PBT+50\%$ peatmoss. A commercial plug medium (Tosilee) was used as the control. All seeds were sown in 128 cell plug trays on July 12, 2004. Seedling growth was measured at 30 days after sowing. Percent seed germination was greater than 95% in all treatments. Plant height, shoot fresh and dry weights, leaf area, and hypocotyl length were the greatest in the control treatment. Root length and weight were the greatest in the $100\%$ PBT treatment, which had a medium pH of 7.3. Leaf area and shoot dry weight were greater in the $50\%$ $PBT+50\%$ peatmoss treatment, than in the $100\%$ PBT treatment, while they were the smallest in the $100\%$ peatmoss treatment. No toxicity symptoms caused by the use or PBT had been observed in any treatment. The results suggest a possibility of recycled PBT, a valuable reusable resource, to be used as a component for medium amendments in horticultural transplant production.

Optimization for the Lactic Acid Fermentation of Mixed Fruit and Vegetable Juices (젖산발효에 의한 혼합과채음료 제조의 최적화)

  • Kim, Su-Yeun;Choi, Eon-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.34 no.2
    • /
    • pp.303-310
    • /
    • 2002
  • An optimization for fermentation processes to make lactic acid juice with extracts from apples, carrots, celery, watercress, jujube and lycii (3 : 3 : 1 : 1/2 : 1 : 1/2) using co-cultures of Leuconostoc mesenteroides, Lactococcus lactis and Lactobacillus cellobiosus isolated from Dongchimi had been investigated on the emphasis of composition of sugars and sodium chloride at various temperatures. The concentration of sugars less than 25% and salt less than 0.8% did not affect remarkably the cell growth of lactic acid bacteria and acid formation during fermentation. The fermenting juice showed increases in the population of lactic acid bacteria and acidity, and decreases in population of coliform bacteria and sugar concentration with high cultural temperature. At $25^{\circ}C$ viscous substance was not formed as it had at $15^{\circ}C$. The optimum composition, based on the sensory evaluation, was determined to be oligosaccharide and 0.2% for sodium chloride. It took 3 days to produce the most preferable juice of pH 3.62 at $25^{\circ}C$. At the optimal state the fermented juice showed viable cell counts (cfu/mL) of exponential numbers 8 for lactic acid bacteria and 4 for yeast. Coliform bacteria which had been $5.6{\times}10^2\;cfu/mL$ at the beginning of fermentation were not detected.

Effect of Chlorella Extract on Quality Characteristics of Yoghurt (Chlorella 추출물 첨가가 요구르트의 품질 특성에 미치는 영향)

  • 조은정;남은숙;박신인
    • The Korean Journal of Food And Nutrition
    • /
    • v.17 no.1
    • /
    • pp.1-7
    • /
    • 2004
  • Yoghurt base was prepared from skim milk added with 0.25∼2.0%(w/v) of chlorella extract powder and fermented with lactic acid bacteria(Streptococcus thermophilus : Lactobacillus casei = 1:1) at 37$^{\circ}C$ for 24 hours. Quality characteristics of the yoghurts were evaluated in terms of acid production, number of viable cell, color, texture property, and sensory property during lactic acid fermentation. The addition of 0.25% chlorella extract powder stimulated the growth of lactic acid bacteria which showed the highest number of viable cell counts(l.46${\times}$10$\^$8/ CFU/mL) after 12 hours incubation, and also enhanced the acid production which was pH 4.33 after 12 hours incubation. The L values(brightness) of the yoghurts containing chlorella extract powder were lower than control group, whereas the b values(yellowness) were higher. The hardness and gumminess of the yoghurt added with 0.25% chlorella extract powder were higher than others. Sensory scores of the yoghurt added with 0.25% chlorella extract powder were significantly higher than other groups in color, chlorella odor, sweet taste, chlorella taste, mouth feel, aftertaste and overall acceptability.

REDIFFERENTIATION FROM TISSUE CULTURE AND ISOLATION OF VIABLE PROTOPLASTS IN PANAX GINSENG C.A. MEYER (고려인삼의 조직배양에 의한 기관형성과 원형질체배양에 관한 연구)

  • Choi Kwang-Tae;Yang Deok-Chun;Kim Nam-Won;Ahn In-Ok
    • Proceedings of the Ginseng society Conference
    • /
    • 1984.09a
    • /
    • pp.1-11
    • /
    • 1984
  • Ginseng cotyledon calli were cultured on 1/2MS media supplemented with combination of various growth regulators to induce more embryoids and plantlets in a short period. And tissues of ginseng root and calli were also incubated under various factors or conditions to establish methods for the isolation of viable protoplasts in Panax ginseng C.A. Meyer. The calli derived from cotyledon produced numerous embryoids in 1/2MS media containing 0.5mg/$\ell$ 2,4-D and 0.5mg/$\ell$ kinetin after 2 months' culture. But only shoot formation was less frequent. Further development of these embryoids occurred on 1/2MS medium supplemented with the same concentration of BA and GA. Viable protoplasts were isolated from the root tissue and callus of ginseng. The specific conditions for the isolation of viable protoplasts were required of ginseng materials, root tissue and callus, being processed. For the production of viable protoplasts from 1-year old ginseng root tissue, an enzyme mixture of $2\%$ cellulase 'Ono-zuka' and $0.5\%$ macerozyme, an enzyme solution pH of 5.2 to 5.8, a 7- to 8- hour incubation period at $28{\pm}1^{\circ}C$, and 0.9M mannitol as osmoticum in the cell enzyme mixture were optimum, while the treatments with an enzyme mixture of $2\%$ cellulase 'Onozuka', $2\%$ macerozyme and $1\%$ driselase, and 25-hour incubation period at $28{\pm}1^{\circ}C$, were more efficient for the production of viable protoplasts from ginseng callus.

  • PDF