 หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : Effect of Acetic Acid on Growth and Ethanol Fermentation of Xylose Fermenting Yeast and Saccharomyces cerevisiae) ผู้เขียน: ดร.สาวิตรี ลิ่มทอง, ศาสตราจารย์ ,  ธวัชชัย สุ่มประดิษฐ, ดร.วิเชียร กิจปรีชาวนิช, รองศาสตราจารย์ , Manee Tuntirungkij, Tatsuji Seki, Toshiomi Yoshida สื่อสิ่งพิมพ์:pdf AbstractGrowth of some xylose fermenting yeasts, Candida shehatae, Pichia stipitis CBS5773, fusant F101 and fusant F198, was completely inhibited in xylose medium added with 0.5% v/v acetic acid which caused the reduction of pH to 4.1. Only one xylose fermenting strain, Pachysolen tannophilus NRRL-Y2460, showed relatively low growth and ethanol fermentation. However, in the medium added with 1.0% v/v acetic acid (pH 3.7) all of these strains were completely inhibited. When the medium was adjusted by hydrochloric acid to pH 4.1 and 3.7, all xylose fermenting strains showed almost the same growth as in the medium without pH adjustment (pH 6.2). In glucose medium added with 0.5% v/v acetic acid, various strains of Saccharomyces cerevisiae, M30, Sc90, N1, G/3, G/5, G/2, TJ3 and SH1089, grew with lower specific growth rate and provided lower maximal cell concentration rate than in medium without adding acetic acid (pH 6.2). All strains, except N1, produced slightly higher maximal ethanol concentration. However, all of them yielded lower ethanol production rate. Among S. cerevisiae, strain B120 was more sensitive to acetic acid than the others since its growth was completely inhibited by 0.5% v/v acetic acid. In glucose medium, 0.5% v/v acetic acid did the same role as in xylose medium to xylose fermenting strains. Hence, the xylose fermenting yeasts revealed higher sensitivity to acetic acid than S. cerevisiae. |
หัวเรื่อง:ไม่มีชื่อไทย (ชื่ออังกฤษ : The Influence of Serum Concentration on tPA Production of CHO Cell) ผู้เขียน:Teerapatr Srinorakutara, Jin-Ho Jang, Mutsumi Takagi, Toshiomi Yoshida สื่อสิ่งพิมพ์:pdf AbstractThe effect of initial serum concentration on cell growth, and the production of tissue plasminogen activator (tPA) is investigated across batch fermentation of a Chinese hamster ovary (CHO) growing in newborn calf serum (NCS) medium. It was found that initial serum concentration influenced on CHO cell growth rate and cell yield. At high-serum content, the uptake rate of glucose decreased although the specific growth rate was higher, indicating a serum component becoming growth limiting. An average glucose uptake rate in 10% (v/v) NCS medium was 13.84 mg/106 cells/h as in 1% (v/v) NCS medium was 18.17 mg/106 cells/h. It was also found that the tPA or the maximum tPA productions increased with initial serum concentration. At 7.12% NCS, the maximum tPA production gave the highest value (5.55 mg/l). The effect of initial serum concentration on the main product was similar to that of major by-product (e.g. lactate and ammonia). |
หัวเรื่อง:อิทธิพลของเกลืออนินทรีย์บางชนิดต่อการเจริญและการหมักแอลกอฮอล์ของ Saccharomyces cerevisiae AM 12 ผู้เขียน:ดร.สาวิตรี ลิ่มทอง, ศาสตราจารย์, Toshiomi Yoshida, Tatsuji Seki, นางมาลี สุวรรณอัตถ์ , Hisaharu Taguchi สื่อสิ่งพิมพ์:pdf Abstract The effect of some inorganic salts on growth and ethanol fermentation of a fusant, Saccharomyces cerevisiae AM 12 was studied. The concentration of inorganic salts used in this study was based on concentration of inorganic ions contained in each salt. The concentration used was 3 levels which were equal to, two times and four times higher than the concentration of inorganic ions in molasses diluted to make the sugar concentration appropriate for ethanol fermentation, about 20% by weight. The results indicated that CaCl2 at all tested concentrations showed strongly inhibition on growth at nearly the same level but inhibited ethanol fermentation at little different level. NH4Cl inhibited growth and fermentation strongly but less than CaCl2 did. (NH4)2 SO4 showed similar effects with NH4Cl. The ion which effect on growth and fermentation of these two salts, (NH4)2SO4 and NH4Cl was ammonium ion. KCl at all tested concentration did not show inhibition on fermentation. NaCl at the concentration of sodium ion equal to the concentration in diluted molasses for ethanol fermentation showed no inhibition on both growth and ethanol fermentation. |