![world Img](images/cover_science.gif) หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Extracellular Halophilic Ribonuclease from a Halotolerant Pseudomonas sp. : Purification and Characterization) ผู้เขียน: Werasit Kanlayakrit, อนันต์ บุญปาน, Takahiro IKEDA, Somporn Tojai สื่อสิ่งพิมพ์:pdf AbstractA halotolerant bacterium, Pseudomonas sp. No. 3241, isolated from Thai fish sauce obtained in Suratthani province, produced an extracellular ribonuclease when cultivated aerobically without NaCl in Sehgal and Gibbons complex medium (SGC medium). Ribonuclease was purified by ethanol precipitation, Sephadex G-150 gel filtration and DEAE Toyopearl 650M anion-exchange chromatography. The purity and molecular weight were determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The result showed that the molecular weight of ribonuclease from halotolerant Pseudomonas sp. No. 3241 was 61,000 daltons. Purified ribonuclease was optimum at pH 10.0 and at temperature of 40?C. Purified ribonuclease was stable between pH 6.0 and 10.0 and at temperatures between 30 and 40?C. This enzyme had marked halophilic enzyme properties that required an optimum NaCl concentration of 3.0 M (18%). |
![world Img](images/cover_science.gif) หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Isolation and Characterization of Salt-Loving Protease Producing Bacteria form Fish Sauce Samples) ผู้เขียน: Werasit Kanlayakrit, ปรียานุช บวรเรืองโรจน์ สื่อสิ่งพิมพ์:pdf AbstractFermented fish samples from fish sauce factories in the eastern part of Thailand were used as sources for the isolation of salt-loving protease-producing bacteria. The conditions for optimal growth and salt-loving protease production were established for the extremely halophilic bacteria. Two hundred and eighty five strains of halophilic bacteria were isolated. Among these isolated strains, a totally ten strains of extremely halophilic bacteria exhibited the highest salt-loving proteases producing ability. Maximal growth and salt-loving proteases of these strain occurred in mM73 agar medium at 4M (24 %, w/v) NaCl. On the other hand, bacterial growth and salt-loving protease activity did not occur when NaCl concentration in mM73 agar medium was lowered to 2M (12 %, w/v). All of these strains were further secondary screened in liquid medium. These selected strains were cultured on a rotary shaker at 200 rpm at 37 ?C in M73 liquid medium with 4M (24 %, w/v) NaCl at pH 7. The bacteria strain PB407 exhibited the highest salt-loving protease activity. In addition, the strain PB407 was identified and characterized. It was a Gram-negative, rod. The colonies were circle with red pigmentation. Growth occurred in a medium containing 17.5-25 % NaCl. Based on the data obtained in this study, it was concluded that the extremely halophilic bacteria strain PB407 belonged to the genus Halobacterium. |
![world Img](images/cover_science.gif) หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Isolation and Characterization of Extracellular Halophilic Ribonuclease from Halotolerant Pseudomonas species) ผู้เขียน: Werasit Kanlayakrit, Takahiro IKEDA, Somporn Tojai, ดร.มังกร โรจน์ประภากร, รองศาสตราจารย์ , ดร.สาโรจน์ ศิริศันสนียกุล, ศาสตราจารย์![](ForestImages/Avata/Person/270024.jpg) สื่อสิ่งพิมพ์:pdf AbstractA halotolerant bacterium isolated from Thai fish sauce, obtained in Surathani province, was identified as a Pseudomonas sp. No. 3241. This strain showed halophilic ribonuclease activity. When casamino acids (CA) and yeast extract (YE) were used as the nitrogen source in a mini jar fermenter, a ratio concentration of CA to YE of 15:20 g/l in Sehgal and Gibbons Complex (SGC) medium, without NaCl, gave maximum growth and ribonuclease activity (18.18 U/ml). The ribonuclease enzyme was optimal at pH 10.0 and at the temperature of 50?C. It had marked halophilic enzyme properties that required an optimal NaCl concentration of 3 M. The ribonuclease was stable between pH 6.0 and 9.0 and at temperatures between 30 and 40?C. |
![world Img](images/cover_science.gif) หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Production of Seasoning “Mirin” from Thai Rice by Fermentation) ผู้เขียน: Werasit Kanlayakrit, เมทินี มาเวียง สื่อสิ่งพิมพ์:pdf AbstractThe investigation of the use of Aspergillus oryzae strain and Thai non-glutinous rice varieties, which are suitable for enzyme production for koji preparation was carried out. A. oryzae strain no. WM-2 could produce a-amylase enzyme at the highest level while “Leung 11”, a non-glutinous rice variety was the most suitable for koji preparation because of its unaggregation characteristics which are good for enzyme production (31.71 units/ml of a-amylase and 6.66 units/ml of acid protease). The suitable ratio of solid:liquid content for mirin production was also studied and it was found that the ratio of 60:40 was the most appropriate because it gave rather pale color and suitable residual alcohol concentration (13 % v/v). This ratio was subsequently used for the determination of an appropriate ratio of koji to glutinous rice. The result indicated that the ratio of koji to glutinous rice of 1:7 gave good quality mirin when comparing with the commercial mirin. Based on the scaling-up of koji preparation, it was found that the cultivation time of 36 h gave the highest activities of a–amylase and protease, which are suitable for mirin production. Ten kilograms of rice koji with 1.0 inch bed thickness gave suitable conditions for enzyme production (322.0 units/g dry wt. of a–amylase and 150.82 units/g dry wt. of acid protease). The results from the study were used for pilot-scale mirin production (50 kg). Ninety per cent of the untrained panelists accepted the quality of mirin produced at the above-mentioned conditions. |
![world Img](images/cover_science.gif) หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Screening of Halophilic Lipase-Producing Bacteria and Characterization of Enzyme for Fish Sauce Quality Improvement) ผู้เขียน: Werasit Kanlayakrit, อนันต์ บุญปาน สื่อสิ่งพิมพ์:pdf AbstractTwenty pure bacterial cultures isolated from Thai fish sauce were selected for lipase producing on Sehgal and Gibbons Complex (SGC)-Tween 80 agar containing 0-4 M NaCl. The results showed that isolate PB233 could produce the highest lipase activity. This isolate was identified based on morphological, physiological characteristics and compared 16S rRNA sequence to other bacteria. It was concluded that isolate PB233 belonged to Staphylococcus warneri. This strain could grow in 0-4 M NaCl but the best growth was observed at 0 M NaCl. Therefore, Staphylococcus warneri was classified as halotolerant bacteria. A halotolerant Staphylococcus warneri PB233 was cultured in mini jar fermenter using SGC medium containing 1% olive oil and 3 M NaCl. A typical pattern of lipase production showed that enzyme secretion was coupled to active cell multiplication and maximum activity was obtained at a stationary phase. The maximum production of lipase (90.12 U/ml) was observed at 48 hr. The lipase had optimum at pH 7.0 and at temperature of 40?C. It was stable between pH 7.0 and 9.0 and at temperatures between 30 and 40?C. This enzyme had marked halophilic enzyme properties and showed maximal activities in the presence of 2.5 M (15%) NaCl. |
![world Img](images/cover_science.gif) หัวเรื่อง:การปรับสภาพที่เหมาะสมด้วยวิธีทางเคมีชีวภาพและกายภาพสำหรับการย่อยสลายยีสต์ขนมปังเพื่อผลิตยีสต์สกัด ผู้เขียน: นายประศาสตร์ ฟูตระกูล, ผู้ช่วยศาสตราจารย์ , Supot BOONRAENG, Weerasit Kanlayakrit, Charan Chetanachitra สื่อสิ่งพิมพ์:pdf AbstractThe effects of chemical, biochemical and physical treatments on baker?s yeast lysis were studied. The standard conditions for autolysis were pH 5.2, temperature 54?C and yeast concentration 13% dry wt. The optimum chemical treatment obtained by using 5% v/v ethanol and 5% w/v NaCl. The optimum biochemical and physical treatments were the use of 0.1%w/w of papain and 8,000 psi of homogenization respectively. The combination treatment of 5% ethanol and 5% NaCl exhibited highest protein content (61.90%).The physical treated sample obtained 42.45% of total carbohydrate yield and biochemical treated sample obtained 46.53% of autolysate. The chemical analysis of the samples showed the best result in the biochemical treated sample as (g/100g dry wt): 57.50 of total protein, 8.22 of amino-nitrogen, 24.27 of carbohydrate, 7.86 of nucleic acid and 10.72 of ash contents. This treatment showed the feasibility of producing yeast extract, yeast autolysate at pilot plant or industrial scale. |
![world Img](images/cover_science.gif) หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effects of Chemical, Biochemical and Physical Treatments on the Kinetics and on the Role of Some Endogenous Enzymes Action of Baker’s Yeast Lysis for Food-Grade Yeast Extrac ผู้เขียน: S. Boonraeng, P. Foo-trakul, W. Kanlayakrit, C. Chetanachitra สื่อสิ่งพิมพ์:pdf AbstractThe effects of chemical, biochemical and physical treatments on lysis of baker’s yeast cells were studied at pH 5.2 and temperature 54 ?C. An unstructured kinetic model of first order was developed to understand the mechanism of yeast lysis. The autolysis rate constant (k), yield factor for protein (?P), total carbohydrate (?C) and autolysate (?A) were sensitive to disruption methods. Since there were endogenous enzymes in the yeast cells such as proteinases, glucanases and carboxypeptidases, these enzymes were responsible for synergistic of cell disruption and their activity profiles were affected by different treating methods. From the determined results of amino acids composition in yeast autolysate, there were differences in amino acid content. The biochemical treated sample using 0.1% papain gave the highest total amino acid content among all analysed samples. |
![world Img](images/cover_science.gif) หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Production and Characterization of Protease from an Extremely
Halophilic Halobacterium sp. PB407) ผู้เขียน: Werasit Kanlayakrit, ปรียานุช บวรเรืองโรจน์, Takuji Oka, Masatoshi Goto สื่อสิ่งพิมพ์:pdf AbstractIn order to accelerate the fish sauce fermentation by using enzyme, the production of protease from
Halobacterium sp. PB407 isolated from Thai fish sauce was investigated. This strain could produce high
protease inM73 medium containing 4 M (24%, w/v) NaCl, pH 7.0 at 37?C in shaking condition for 5days.
Its production of protease in 2.5 L mini jar fermentor was investigated at 37?C, 50 rpm agitation and
aeration at 0.5 vvm. The protease production time was shorten to only 96 hrs. The optimum pH and
temperature for maximal protease activity was 8.0 and 40?C, respectively. This protease had marked
halophilic properties, showing maximum activities in the presence of 2.13 M NaCl. In addition, this
Halobacterium sp. PB407 was further identified. Based on 16S rRNA sequence data, the bacteria was
concluded as a Halobacterium salinarum. |