• Title/Summary/Keyword: Mold Growth

Search Result 405, Processing Time 0.033 seconds

Effect of Chlorine Dioxide, Cold Plasma Gas Sterilization and MAP Treatment on the Quality and Microbiological Changes of Paprika During Storage (이산화염소 및 저온 플라즈마 가스 살균 및 MAP 처리가 파프리카의 저장 중 품질과 미생물학적 변화에 미치는 영향)

  • In-Lee, Choi;Joo Hwan, Lee;Yong Beom, Kwon;Yoo Han, Roh;Ho-Min, Kang
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
    • /
    • v.28 no.3
    • /
    • pp.223-229
    • /
    • 2022
  • This study was conducted to investigate the effect of packaging methods and sterilization treatment on storability and microbial control in paprika fruits. When treated with chlorine dioxide gas for 3, 6, and 12 hours and cold plasma gas for 1, 3, and 6 hours, and then packed in a carton box and stored in a 8 ± 1℃ chamber for 7 days, chlorine dioxide treated 12 hours and plasma treated 6 hours was prevented the development of E·coli and YM(yeast and mold). Accordingly, the control was treated with chlorine dioxide for 12 hours and plasma for 6 hours, packed using a carton box and 40,000 cc·m-2·day-1·atm-1 OTR film (MAP), and stored in a 8 ± 1℃ chamber for 20 days. Fresh weight loss rate during storage was less than 1% in the MAP treatments, and the visual quality of the MAP treatments was above the marketability limit until the end of storage. There was no difference in the contents of oxygen, carbon dioxide, and ethylene in the film. In the case of firmness, the chlorine dioxide treatments was low, and the Hunter a* value, which showed chromaticity, was highest in the Plasma 6h MAP treatment. Off-odor was investigated in the MAP treatments, but it was very low. The rate of mold growth on the fruit stalk of paprika was the fastest and highest in the chlorine dioxide treated box packaging treatments, and the lowest in the chlorine dioxide treated MAP treatments at the end of storage. The aerobic count in the pulp on the storage end date was the lowest in the plasma treated box packaging treatments, the lowest number of E·coli in the chlorine dioxide treated MAP treatments, and the lowest yeast & mold in the chlorine dioxide treated box packaging treatments. As a result, for the inhibition of microorganisms during paprika storage, it is considered appropriate to treat plasma for 6 hours before storage regardless of the packaging method.

Effects of Oak Wood Vinegars on Mycelial Growth, Fruiting Body Production, and Mushroom Quality of Lentinula edodes (참나무류 목초액이 표고의 균사생장, 버섯 생산량 및 품질에 미치는 영향)

  • Shin, Keum Chul;Kim, Nam Kyu;Cho, Jong Won;Lee, Sang Yong;Lee, Jong Kyu
    • Journal of Korean Society of Forest Science
    • /
    • v.97 no.1
    • /
    • pp.35-44
    • /
    • 2008
  • Mycelial growth of Lentinula edodes on solid or liquid culture media supplemented with differentconcentrations of oak wood vinegar varied depending on the types of wood vinegar or mushroom varieties used.Oak wood vinegar obtained from traditionally carbonizing kiln (TWV) inhibited mycelial growth of L. edodes atthe dilution level of less than $5{\times}10^{-2}$, but stimulated at $10^{-3}$ to $2{\times}10^{-3}$. Wood vinegar from mechanicallycarbonizing kiln (MWV) inhibited at $10^{-3}$, but stimulated at $2{\times}10^{-3}$. In liquid culture media, both wood vinegarinhibited at $5{\times}10^{-2}$, but stimulated at $2{\times}10^{-3}$. Sanjo-302-ho grown in liquid culture media at $2{\times}10^{-3}$, and Sanrim 2and 3-ho grown at $4{\times}10^{-3}$ showed relatively high degree of wood decay (DWD) and growing ability within wood(GAWW) when these isolates were inoculated onto oak wood logs. TWV completely inhibited mycelial growth ofgreen mold fungi, Trichoderma species, tested at $5{\times}10^{-1}$ dilution level, while MWV inhibited at $5{\times}10^{-1}$ to $5{\times}10^{-2}$dilution level. For Diatrype stigma, TWV inhibited mycelial growth at the dilution level of less than $5{\times}10^{-2}$, whileMWV did 80% of mycelial growth at $10^{-2}$, and 100% at $5{\times}10^{-1}$ dilution level. Fresh and dry weight of fruitingbodies harvested after soaking of wood logs into wood vinegar solutions with different concentrations werecompared, and were the highest at $2.5{\times}10^{-2}$ dilution level. Storage test of fruiting bodies at $10^{\circ}C$ for 10 daysshowed that fruiting bodies harvested after soaking in the solution with $2.5{\times}10^{-2}$ dilution level showed the bestfreshness by general test and color changes. In addition, shear force value of L. edodes fruiting bodies measuredby using texture analyzer showed that $2.5{\times}10^{-2}$ dilution level was the best concentration for keeping flesh texture.

A study of the manual procedure of ocular prosthesis (의안의 제조 방법에 관한 연구)

  • Kim, Jai Min;Park, Dong Hwa;Yoo, Geun Chang;Kim, Soon Ae;Cho, Seung Kwon
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.7 no.2
    • /
    • pp.95-99
    • /
    • 2002
  • To investigate the manual procedure for custom fitting of ocular prosthesis and the cytotoxicity induced by extract solution of prosthetic eye, this study was performed. These procedures included the trial fitting of the wax model, impression molding, the an of iris color duplication, sclera mold made from the prosthetic wax model, scleral tints and vascular pattern, finishing and polishing. Inhibition of cell growth for extract solution was measured by MTT assay. Extract solution did not show the cytotoxicity. This study suggests that the manual procedure for custom fitting of ocular prosthesis is good for education of students.

  • PDF

Effects of Synbiotics Containing Anaerobic Microbes and Prebiotics on In vitro Fermentation Characteristics and In situ Disappearance Rate of Fermented-TMR

  • Lee, Shin-Ja;Shin, Nyeon-Hak;Chu, Gyo-Moon;Lee, Sung-Sill
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.24 no.11
    • /
    • pp.1577-1586
    • /
    • 2011
  • This study was carried out to estimate effects of synbiotics containing anaerobic microorganisms and prebiotics on in vitro fermentation characteristics and in situ disappearance rate of fermented total mixed ration (F-TMR). For the in vitro trial, ninety vinyl bags were prepared to analyze temperature, pH, ammonia concentration, microbial growth rate and short chain fatty acid concentration. For the in situ trial, one hundred twenty nylon bags were prepared to analyze dry matter (DM), acid detergent fiber (ADF) and neutral detergent fiber (NDF) disappearance rate. Treatments consisted of a basal diet (US) with prebiotics and probiotics from anaerobic mold (MS), bacteria (BS), yeast (YS) or compound (CS). It was found that temperatures at 14 and 21 days were significantly higher (p<0.05) in the YS and CS than in the others. The pH at 21 days was lower in the CS than in the US. The synbiotic treatments had significantly increased (p<0.05) ammonia concentration at 21 days. The DM disappearance at 72 h was significantly higher (p<0.05) in the MS and CS than in the others. ADF and NDF disappearance rate tended to increase at a rate similar to the DM disappearance rate. Therefore, this study suggests that synbiotics (probiotics with prebiotics) may partially help the quality of fermentation and digestibility of TMR (MS and CS) as fiber disappearance.

Micro/Millimeter-Wave Dielectric Indialite/Cordierite Glass-Ceramics Applied as LTCC and Direct Casting Substrates: Current Status and Prospects

  • Ohsato, Hitoshi;Varghese, Jobin;Vahera, Timo;Kim, Jeong Seog;Sebastian, Mailadil T.;Jantunen, Heli;Iwata, Makoto
    • Journal of the Korean Ceramic Society
    • /
    • v.56 no.6
    • /
    • pp.526-533
    • /
    • 2019
  • Indialite/cordierite glass-ceramics demonstrate excellent microwave dielectric properties such as a low dielectric constant of 4.7 and an extremely high quality factor Qf of more than 200 × 103 GHz when crystallized at 1300℃/20 h, which are essential criteria for application to 5G/6G mobile communication systems. The glass-ceramics applied to dielectric resonators, low-temperature co-fired ceramic (LTCC) substrates, and direct casting glass substrates are reviewed in this paper. The glass-ceramics are fabricated by the crystallization of glass with cordierite composition melted at 1550℃. The dielectric resonators are composed of crystallized glass pellets made from glass rods cast in a graphite mold. The LTCC substrates are made from indialite glass-ceramic powder crystallized at a low temperature of 1000℃/1 h, and the direct casting glass-ceramic substrates are composed of crystallized glass plates cast on a graphite plate. All these materials exhibit excellent microwave dielectric properties.

Preparation and Treatment of Sulfur Dioxide Gas Generating Agent for Storage of Grape Fruits (포도 저장을 위한 아황산가스 발생제의 제조 및 처리 방법)

  • Choi, Seong-Jin
    • Food Science and Preservation
    • /
    • v.15 no.6
    • /
    • pp.791-795
    • /
    • 2008
  • In order to establish the method to prepare and use the sulfur dioxide gas generating agent in low temperature storage of grape fruits, the $SO_2$ generation capacity from various sulfite compounds was investigated, and the method to regulate $SO_2$ gas generation and to detect the gas was developed. The conidial germination and mycelium growth of Botrytis cinerea which causes gray mold disease during grape fruit storage was completely inhibited at the $SO_2$ gas concentration of 400 ppm and 3200 ppm, respectively. Sodium hydrosulfite generated the most amount of $SO_2$ gas among the investigated 5 different sulfite or bisulfite compounds. By adjusting the number of pinholes on packaging film of the compound or by adding pH adjusting agent, e.g. citric acid or phosphates, it was possible to regulate the amount and duration of $SO_2$ gas generation from the compound. Because malachite green was quantitatively discolored by $SO_2$ gas, the solution or impregnated paper with the compound could be practically utilized as a indicator detecting $SO_2$ gas. Finally, when Muscat Bailey A grape was stored at low temperature with $SO_2$ gas generating agent, the disease incidence was reduced after storage.

Isolation and Characterization of an Alkaline Cellulase Produced by Alkalophilic Bacillus sp. HSH-810 (알칼리성 Cellulase를 생산하는 호알칼리성 Bacillus sp. HSH-810의 분리 및 효소 특성)

  • 김지연;허성호;홍정화
    • Korean Journal of Microbiology
    • /
    • v.40 no.2
    • /
    • pp.139-146
    • /
    • 2004
  • A bacterium producing alkaline cellulase was isolated from soil, leaf mold and compost, and was identified as alkalophilic Bacillus sp. HSH-810 by morphological, cultural and biochemical determination. The optimum cul-ture condition of Bacillus sp. HSH-810 for the growth and alkaline cellulase production was $30^{\circ}C$ and pH 10.0. The maximum alkaline cellulase production was obtained when 1.0%(w/v) CMC, 0.5%(w/v) peptone, 0.02%(w/v) $CaCl_2$ and 0.02(w/v) $CoCl_2$ were used as carbon source, nitrogen source and mineral source, respectively. The optimum pH and temperature of the enzyme activity were pH 10.5 and $50^{\circ}C$, respectively. This enzyme was fairly stable in the pH range of 6.0-13.0 and at $50^{\circ}C$. For the effect of surfactants, the activity of alkaline cellulase was stable in the presence of sodium-$\alpha$-olefin sulfonate (AOS), sodium dodecyl sulfonate (SDS), Tween 20 and Tween 80, but inhibited by the presence of 0.1 linear alkyl-benzene sulfonate (LAS) sig-nificantly.

Identification and Characterization of Trichoderma Species Damaging Shiitake Mushroom Bed-Logs Infested by Camptomyia Pest

  • Kim, Jun Young;Kwon, Hyuk Woo;Yun, Yeo Hong;Kim, Seong Hwan
    • Journal of Microbiology and Biotechnology
    • /
    • v.26 no.5
    • /
    • pp.909-917
    • /
    • 2016
  • The shiitake mushroom industry has suffered from Camptomyia (gall midges) pest, which feeds on the mycelium of shiitake mushroom during its cultivation. It has been postulated that fungal damage of shiitake bed-logs is associated with infestation by the insect pest, but this is not well understood. To understand the fungal damage associated with Camptomyia pest, various Trichoderma species were isolated, identified, and characterized. In addition to two previously known Trichoderma species, T. citrinoviride and T. deliquescens, two other Trichoderma species, T. harzianum and T. atroviride, were newly identified from the pestinfested bed-log samples obtained at three mushroom farms in Cheonan, Korea. Among these four species, T. harzianum was the most evident. The results of a chromogenic media-based assay for extracellular enzymes showed that these four species have the ability to produce amylase, carboxyl-methyl cellulase, avicelase, pectinase, and ß-glucosidase, thus indicating that they can degrade wood components. A dual culture assay on PDA indicated that T. harzianum, T. atroviride, and T. citrinoviride were antagonistic against the mycelial growth of a shiitake strain (Lentinula edodes). Inoculation tests on shiitake bed-logs revealed that all four species were able to damage the wood of bed-logs. Our results provide evidence that the four green mold species are the causal agents involved in fungal damage of shiitake bed-logs infested by Camptomyia pest.

Isolation and physiological characteristics of cellulolytic bacteria (섬유소 분해세균의 분리 및 생리적인 특성)

  • Kwon, Oh-Jin;Chung, Yung-Gun
    • Applied Biological Chemistry
    • /
    • v.37 no.4
    • /
    • pp.226-233
    • /
    • 1994
  • Three hundred and one cellulolytic bacterial were isolated from the 148 screening sources such as decomposed wood, soil, compost and leaf mold. Among them, strain KL-6 was found to have the highest of cellulase activity, and identified as species belonged to the genus Cellulomonas. Strain KL-6 was decompose up to 90% of the filter paper (whatman No. 1) substrate within 50 hours, and showed the colony halo formation (11 cm). The activities of CMCase (67 unit/ml), FPase (70 unit/ml) and ${\beta}-glucosidase$ (0.68 unit/ml) were obtained when this strain was cultured for 50 hrs at $30^{\circ}C$. Glucose was not found in detectable amounts at the FP medium. The optimum composition of nutrient medium for the cell growth by strain KL-6 was sucrose 0.5%, yeast extract 0.1%, $(NH_4)_2HPO_4\;0.1%$, $K_2HPO_4\;0.1%$, $MgSO_4{\cdot}7H_2O\;0.01%$, $CaCl_2\; 0.01%$, NaCl 0.6%, $CaCO_3\;0.1%$ and the optimum pH and temperature were 7.0 and $30^{\circ}C$, respectively.

  • PDF

Seasonal distribution of microorganisms in the effluent water in various sewage treatment plants (하수처리장 방류수의 계절별 미생물분포에 관한 연구)

  • Kim, Young-Jun;Chung, Myung-Hee;Chung, Doo-Young;Lee, Hye-Young
    • Journal of the Korea Organic Resources Recycling Association
    • /
    • v.16 no.1
    • /
    • pp.53-61
    • /
    • 2008
  • Seasonal distribution of various microorganisms was investigated in the effluent water in various sewage treatment plants from January to November in 2007. The target microorganisms were composed of total heterotrophic bacteria, Escherichia coli, coliform and enteric bacteria, Staphylococcus aureus, Yeast and Mold. The number of total bacteria and the indicator microorganisms, such as E. coli, coliform, and Enterobacteriacea, were increased during the summer season. S. aureus, however, was not influenced by the weather, showing higher number even in November and January in most sewage treatment plants investigated. Meanwhile, disinfection methods employed in various plants had no direct relationship with the growth of microorganisms, and small-scaled plants were found to be more effective than large-scaled ones in the sterilization of microorganisms.

  • PDF