• Title/Summary/Keyword: Autoclaving

Search Result 182, Processing Time 0.027 seconds

Hydrothermal Synthesis of Saponite from Talc (활석을 이용한 사포나이트의 수열합성)

  • 배인국;장영남;채수천;류경원;최상훈
    • Journal of the Mineralogical Society of Korea
    • /
    • v.16 no.2
    • /
    • pp.125-133
    • /
    • 2003
  • Saponite was synthesized from talc by hydrothermal method. The starting material was prepared by adding ($NO_3$)$Al_3$$.$$9H_2$O and Mg($NO_3$)$_2$$.$$6H_2$O solution to the talc powder. which was previously activated in air at 800 $^{\circ}C$ together with $Na_2$$CO_3$. The alkalinity of the solution was controlled by $NH_4$OH solution. The autoclaving was carried out in the closed stainless steel vessel (about 1 liter) for 40 hours under the pressure of 25 kgf/$\textrm{cm}^2$ at $ 230^{\circ}C$ The characterization of the reaction product shows that saponite was crystallized successfully. After the experimental results, pressure was not sensitive parameter in the range of 25 ∼ 75 kgf/$\textrm{cm}^2$, but longer reaction time results in better crystallinity.

Study on Development of Novel Biopesticides Using Entomopathogenic Bacterial Culture Broth of Xenorhabdus and Photorhabdus (Xenorhabdus 및 Photorhabdus 세균 배양액을 이용한 생물농약 개발에 관한 연구)

  • Seo, Sam-Yeol;Kim, Yong-Gyun
    • Korean journal of applied entomology
    • /
    • v.49 no.3
    • /
    • pp.241-249
    • /
    • 2010
  • Two groups of entomopathogenic bacteria, Xenorhabdus and Photorhabdus, are known to suppress insect immune responses by inhibiting eicosanoid biosynthesis. This study used these bacterial culture broths to develop novel biochemical insecticides against the diamondback moth, Plutella xylostella. Though the bacterial culture broths alone showed little insecticidal activity, they significantly enhanced pathogenicity of Bacillus thuringiensis against the fourth instar larvae of P. xylostella. Sterilization of the bacterial culture broth by autoclaving or $0.2\;{\mu}m$ membrane filtering did not influence the synergistic effect on the pathogenicity of B. thuringiensis. Three metablites identified in the culture broth of X. nematophila also showed similar synergistic effects. In field test, both entomopathogenic bacterial culture broth also enhanced the control efficacy of B. thuringiensis against P. xylostella.

Comparison of Contact Lenses and Storage Solution for Cytotoxic Potential using a Cell Growth Inhibition Assay (소프트 콘택트렌즈 용출액과 보존 용액의 세포 독성 비교)

  • Kim, Jai-Min;Seong, Jeong-Sub;Yoo, Keun-Chang;Yoon, Young;Ra, Myung-Suk;Lee, Jong-Bin
    • Journal of Korean Ophthalmic Optics Society
    • /
    • v.4 no.2
    • /
    • pp.81-86
    • /
    • 1999
  • Human corneal epithelial cells and mouse fibroblast L929 cells were grown to 60-70% confluency in 96 well plates. 24 hours after the well plates are inoculated, the medium on the test plates is aspirated and replaced with an extract supplemented medium prepared from the materials to be tested. The contact lenses manufactured by 7 companies were collected from optical shops and used for this study. The exactracts having been prepared by autoclaving 8 lenses in 2.5ml saline. The cell monolayer is then cultured for a further 48 hour period. MTT and SRB assys were performed for cytotoxic effect on cultured cells An inhibition of 30% is considered clear indication of cytotoxic potential in the test material. All the materials were not cytotoxic, but 3 storage solutions of them inhibited growing L929 cells.

  • PDF

Digestate residues analysis under elevated heat regime by using DNS method

  • Hanif, Mohamad Haziq;Kamaruddin, Mohamad Anuar;Norashiddin, Faris Aiman;Zawawi, Mohd Hafiz
    • Advances in environmental research
    • /
    • v.9 no.1
    • /
    • pp.55-64
    • /
    • 2020
  • The problems with unsorted municipal waste are always associated with disposal issues as it requires a large area for landfilling or high energy used for incineration. In recent years, an autoclaving technique has been considered a promising approach which could minimize the volume of organic waste from being directly disposed or incinerated. In this work, an attempt was done to study the saccharification potential of organic residues under elevated temperature Thermal treatment involving hot water bath was applied to treat the organic residue ranging from 60℃ to 100℃ for 30 and 60 minutes. The result obtained showed an increasing trend for the concentration of glucose and carbohydrate. However, the result for lignocellulose content which contains various component includes extractive, holocellulose, hemicellulose, cellulose and lignin show variation. Based on the thermal treatment carried out, the result indicated that the trend of glucose and carbohydrate content. The highest percentage of glucose that can be obtained 978.602 ㎍/ml which could be obtained at 90℃ at 60 minutes. The carbohydrate also shows an increasing trend with 0.234 mg/ml as the highest peak achieved at 80℃ for 30 minutes treatment. However, it was found that the lignocellulose content varies with temperature and time. The statistical analysis was carried out using two-ways ANOVA shows an interaction effect between the independent variables (temperature and contact time) and the saccharification effects on the food wastes. The result shows a variation in the significant effect of independent variables on the changes in the composition of food waste.

Characteristics of the Bacteriocin from Lactobacillus sp. Oh-B3. (Lactobacillus sp. Oh-B3로부터 생산되는 박테리오신의 특성)

  • 김동섭
    • Microbiology and Biotechnology Letters
    • /
    • v.30 no.2
    • /
    • pp.184-188
    • /
    • 2002
  • A bacteriocin producing microorganism, which inhibits the growth of Lactobacillus sake, was screened and isolated from Kimchi. This microorganism was identified and named as Lactobacillus sp. Oh-B3, The maximum amount of bacteriocin was produced when the isolated microorganism was cultured in MRS media(pH 8.0) for 24 hours at 25℃. The bacteriocin from the isolated microorganism was purified through ammonium sulfate precipitation, dialysis and ultrafiltration. The bacteriocin was stable on the wide pH range of 2.0-9.0, and showed antimicrobial activity on some of gram positive bacteria, not on gram negative. The antimicrobial activity of bacteriocin was mostly removed by treatment of proteolytic enzymes. But, the bacteriocin was very stable on the heat treatment, and more than 50% of activity was remained at autoclaving. The action mode of the bacteriocin showed bacteriocidal pattern, being same as that of general bacteriocins.

An Overlooked Effect of Glycine Betaine on Fermentation: Prevents Caramelization and Increases the $\small{L}$-Lysine Production

  • Xu, Jianzhong;Xia, Xiuhua;Zhang, Junlan;Guo, Yanfeng;Zhang, Weiguo
    • Journal of Microbiology and Biotechnology
    • /
    • v.24 no.10
    • /
    • pp.1368-1376
    • /
    • 2014
  • This article focuses on the effects of glycine betaine on preventing caramelization, and increasing DCW and $\small{L}$-lysine production. The additional glycine betaine not only decreased the browning intensity (decreased 4 times), and the concentrations of 5-hydroxymethylfurfural (decreased 7.8 times) and furfural (decreased 12 times), but also increased the availability of glucose (increased 17.5%) for $\small{L}$-lysine production. The DCW and $\small{L}$-lysine production were increased by adding no more than 20 mM glycine betaine, whereas the DCW and $\small{L}$-lysine production were decreased with the reduction of pH values, although pH had a better response to prevent caramelization than did glycine betaine. For $\small{L}$-lysine production, the highest increase (40%) was observed on the media with 20 mM glycine betaine. The crucial enzymes in glycolysis and $\small{L}$-lysine biosynthesis pathway were investigated. The results indicated that additional glycine betaine increases the activity of enzymes in glycolysis, in contrast to the effect of pH. All the results indicated that glycine betaine can be used to prevent caramelization and increase the $\small{L}$-lysine production. By applying this strategy, glucose would not be have to be separated from the culture media during autoclaving so that factories can save production costs and shorten the fermentation period.

Alcohol Fermentation of Korean Watermelon Juice (수박쥬스의 알콜발효에 관한 연구)

  • Kim, Seong-Lim;Kim, Woo-Jung;Lee, Sang-Yeol;Byun, Si-Myung
    • Applied Biological Chemistry
    • /
    • v.27 no.3
    • /
    • pp.139-145
    • /
    • 1984
  • For the ultimate manufacture of vinegar with watermelon juice, we examined the preliminarily alcoholic fermentation of watermelon juice using Saccharomyces cerevisiae, Saccharomyces cerevisiae var. ellipsoideus and Kluyveromyces fragilis. The juice contained 3.2% total reducing sugar by the Somogyi-Nelson method. Strains of yeast culture, pH, temperature and concentration of sugar in the juice were important factors affecting alcoholic fermentation. Saccharomyces cerevisiae var. ellipsoideus produced 5.3% alcohol from the juice fortified with 12% glucose under the conditions of pH 5.73 and $27^{\circ}C$ for 8 days. Generally, small quantities of various salts and N-sources affected little the alcoholic fermentation of the juice. The sterilization of the juice by autoclaving improved efficiency of fermentation than that by $SO_2$ sterilization. Determination of alcohol was carried out by the gas chromatographic method using Chromosorb W: Carbowax as packing material.

  • PDF

Hydrothermal Synthesis of Smectite from Dickite (딕카이트로부터 스멕라이트의 수열합성)

  • Ryu Gyoung-Won;Jang Young-Nam;Bae In-Kook;Chae Soo-Chun;Choi Sang-Hoon
    • Journal of the Mineralogical Society of Korea
    • /
    • v.17 no.3
    • /
    • pp.267-275
    • /
    • 2004
  • A hydrothermal process was used to synthesize dioctahedral smectite from dickite [$A1_2$$Si_2$$O_{5}$ $(OH)_4$], Dickite was previously activated by heating at $800^{\circ}C$ far 4 hours with $Na_2$$CO_3$. After the heat-treatment, $SiO_2$ was added for stoichiometry, The autoclaving was carried out in closed stainless steel vessel (about 1 liter) at the condition of various temperature, pressure, time etc. High quality smectite could be obtaind by heating at $290^{\circ}C$ under the pressure of 60 kgf/$\textrm{cm}^2$ for 48 hours. This experiment reveals that pH of the solution was an important factor and should be maintained at 10 to 11 for the formation of dioctahedral smectite. The synthesized smectite was identified as Na-beidellite by the treatment of ethylene glycol and Greene-Kelly test.

Comparative Studies on Velvet Deer Antler and Ossified Deer Antler on the Contents of Bioactive Components and on the Bone Mineral Density Improving Activity for Oophorectomized Rat

  • Jo, Sung Jun;Kim, Jung Hwan;Kim, Jeung-Won;Choi, Hye Ok;Lee, Seung Hwan;Kim, Mu-Kang;Woo, Sun Hee;Han, Byung Hoon
    • Natural Product Sciences
    • /
    • v.19 no.4
    • /
    • pp.303-310
    • /
    • 2013
  • Velvet deer antler (VDA) is well known oriental medicine claimed to have tonic activities as improving bone mineral density (BMD), immune-enhancing, rejuvenating and many other medicinal activities. Ossified deer antler (ODA) is bony product produced by over-calcification of deer antler due to late harvesting. The extraction efficiency of ODA by conventional boiling in water must be very poor due to bony nature, hence the reputations for the medicinal efficacies of ODA has been highly under-evaluated compared to that of VDA without any experimental evidences. Employing our new efficient water extraction process ($135^{\circ}C$), the extracts of ODA and VDA were analysed to compare the contents of bioactive components and the potencies of pharmacological activities. The results showed that; 1) The $135^{\circ}C$ extraction (autoclaving) of ODA gave highly increased amount of biomass, 120% more than the conventional extraction by 100-boiling, whereas the same treatment for VDA showed only 15% increased amount of biomass. 2) Feeding the ODA- or VDA-extracts to oophorectomized rats showed very potent BMD-recovering activity. 3) During the ossification of deer antler, the total collagen content was found to be increased by addition of type-1 to pre-existing type-2 collagen, but not replacement of type-2 to type-1 collagen. High titer of peptide hormones like growth hormone and IGF-1 were detected in the ODA- and VDA-extracts and also in the serum of ODA- or VDA-treated oophorectomized animals dose-dependently. Present experimental data will give a conclusion that folkloric poor reputations on ODA must be concerned only with poor extraction efficiency of conventional $100^{\circ}C$ water extraction and not based on the composition of bioactive substances of ODA.

Effects of Heat Treatments on the Dietary Fiber Contents of Rice, Brown Rice, Yellow Soybean, and Black Soybean. (가열처리에 의한 백미, 현미, 노란콩 및 검정콩의 식이섬유 함량 변화)

  • 서우경;김영아
    • Korean journal of food and cookery science
    • /
    • v.11 no.1
    • /
    • pp.20-25
    • /
    • 1995
  • The effects of cooking on the dietary fiber content in rice, brown rice, yellow soybean and black soybean were investigated. The dietary fiber contents were analyzed by Prosky's method(AOAC method) after boiling, microwave heating and autoclaving of the sample. It was showed that the different cooking methods resulted in different effects on the insoluble dietary fiber contents. Except yellow soybean, cooking time had little effect on insoluble dietary fiber contets in the other samples. The contents of soluble dietary fiber were generally increased by cooking. Increased cooking time reduced the content of soluble dietary fiber in brown rice but increased in rice. However, no significant differences caused by cooking time were observed for soluble dietary fiber in black soybean. The effects of cooking method on the total dietary fiber contents were similar to those of insoluble dietary fiber. The reasons for this might be that the main fraction of total dietary fiber was insoluble forms and the content of total dietary fiber was calculated as the sum of insoluble and soluble dietary fiber content.

  • PDF