scholarly journals SELECTION, PRODUCTION AND CHARACTERIZATION OF BACILLUS LIPASE

2011 ◽  
Vol 14 (3) ◽  
pp. 64-72
Author(s):  
Khoa Dang Tran ◽  
Huy Quang Le ◽  
Nghiep Dai Ngo
Keyword(s):  
Bacillus Subtilis ◽  
Liquid Culture ◽  
Culture Medium ◽  
Lipase Production ◽  
Liquid Culture Medium ◽  
Optimum Ph ◽  
Active Lipase ◽  
Substrate Concentrations ◽  
Bacillus Strains

The objective of this study is to screen Bacillus strains for high lipase production; from 10 strains of Bacillus subtilis OII (BS7) has ability the best lipase production. The maximum lipase was carried out using liquid culture medium at pH 7,0, substrate concentrations 1,2% (w/w) after 3 days. The optimum pH and temperature on lipase activity were found to be pH 10,0 and 60 oC respectively. Ion Mn2+, Ca2+ are the ions remain activity; active lipase was inhibited by Cu2+ , Zn2 ; solution of SDS 0,2 % decreases 95% activity. Molecular weight of lipase production by BS7 is approximate 23,8kDa. The results are preconditions for the research on recombinant lipase by Bacillus subtilis OII.

scholarly journals Partial purification and characterization of an endo-α-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242

1992 ◽  
Vol 288 (2) ◽  
pp. 475-482 ◽  
Author(s):  
I Ishii-Karakasa ◽  
H Iwase ◽  
K Hotta ◽  
Y Tanaka ◽  
S Omura
Keyword(s):  
Enzyme Activity ◽  
Culture Medium ◽  
Gel Filtration ◽  
Partial Purification ◽  
Gastric Mucus ◽  
Purification And Characterization ◽  
Streptomyces Sp ◽  
Optimum Ph ◽  
New Type

For the purification of a new type of endo-alpha-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242 (endo-GalNAc-ase-S) [Iwase, Ishii, Ishihara, Tanaka, Omura & Hotta (1988) Biochem. Biophys. Res. Commun. 151, 422-428], a method for assaying enzyme activity was established. Using purified pig gastric mucus glycoprotein (PGM) as the substrate, oligosaccharides liberated from PGM were pyridylaminated, and the reducing terminal sugars of oligosaccharides larger than Gal beta 1-3GalNAc were analysed by h.p.1.c. The crude enzyme of endo-GalNAc-ase-S was prepared as an 80% (w/v) ammonium sulphate precipitate from the concentrated culture medium. The enzyme was partially purified by gel chromatofocusing and subsequent DEAE-Toyopearl chromatography. Endo-enzyme activity eluted around pI 4.8 on a gel chromatofocusing column and eluted with 0.19-0.25 M-NaCl on a DEAE-Toyopearl column. In the enzyme fraction obtained, no exo-glycosidases or proteases could be detected. The molecular mass of the enzyme was estimated as 105 kDa by gel filtration, and the optimum pH was 5.5. Endo-GalNAc-ase-S hydrolysed the O-glycosidic linkage between GalNAc and Ser (Thr) in 3H-labelled and unlabelled asialofetuin, liberating both the disaccharide (Gal beta 1-3GalNAc) and the tetrasaccharide [Gal beta 1-3 (Gal beta 1-4GlcNAc beta 1-6)GalNAc]. When endo-alpha-N-acetylgalactosaminidase from Alcaligenes sp. (endo-GalNac-ase-A) was incubated with 3H-labelled and unlabelled asialofetuin, only the disaccharide (Gal beta 1-3GalNAc) was liberated.

Isolation of previously uncultured rumen bacteria by dilution to extinction using a new liquid culture medium

2011 ◽  
Vol 84 (1) ◽  
pp. 52-60 ◽  
Author(s):  
Nikki Kenters ◽  
Gemma Henderson ◽  
Jeyamalar Jeyanathan ◽  
Sandra Kittelmann ◽  
Peter H. Janssen
Keyword(s):  
Liquid Culture ◽  
Culture Medium ◽  
Rumen Bacteria ◽  
Liquid Culture Medium

scholarly journals FORMATION OF TRYPSIN FROM TRYPSINOGEN BY AN ENZYME PRODUCED BY A MOLD OF THE GENUS PENICILLIUM

1938 ◽  
Vol 21 (5) ◽  
pp. 601-620 ◽  
Author(s):  
M. Kunitz
Keyword(s):  
Temperature Coefficient ◽  
Acid Medium ◽  
Experimental Error ◽  
Protein Concentration ◽  
Liquid Culture ◽  
Culture Medium ◽  
Specific Activity ◽  
Crystalline Form ◽  
Liquid Culture Medium ◽  
Autocatalytic Activation

1. A powerful kinase which changes trypsinogen to trypsin was found to be present in the synthetic liquid culture medium of a mold of the genus Penicillium. 2. The concentration of kinase in the medium is increased gradually during the growth of the mold organism and continues to increase for some time even after the mold has ceased growing. 3. Mold kinase transforms trypsinogen to trypsin only in an acid medium. It differs thus from enterokinase and trypsin which activate trypsinogen best in a slightly alkaline medium. 4. The action of the mold kinase in the process of transformation of trypsinogen is that of a typical enzyme. The process follows the course of a catalytic unimolecular reaction, the rate of formation of a definite amount of trypsin being proportional to the concentration of kinase added. The ultimate amount of trypsin formed, however, is independent of the concentration of kinase used. 5. The formation of trypsin from trypsinogen by mold kinase is not accompanied by any measurable loss of protein. 6. The temperature coefficient of formation of trypsin from trypsinogen by mold kinase varies from Q5–15 = 1.70 to Q25–30 = 1.25 with a corresponding variation in the value of µ from 8100 to 4250. 7. Trypsin formed from trypsinogen by means of mold kinase is identical in crystalline form with the crystalline trypsin obtained by spontaneous autocatalytic activation of trypsinogen at pH 8.0. The two products have within the experimental error the same solubility and specific activity. A solution saturated with the crystals of either one of the trypsin preparations does not show any increase in protein concentration or activity when crystals of the other trypsin preparation are added. 8. The Penicillium mold kinase has a slight activating effect on chymo-trypsinogen the rate being only 1–2 per cent of that of trypsinogen. The activation, as in the case of trypsinogen, takes place only in an acid medium. 9. Mold kinase is rapidly destroyed when brought to pH 6.5 or higher, and also when heated to 70°C. In the temperature range of 50–60°C. the inactivation of kinase follows a unimolecular course with a temperature coefficient of Q10 = 12.1 and µ = 53,500. The molecular weight of mold kinase, as determined by diffusion, is 40,000.

Detection Method for Histamine-Producing, Dairy-Related Bacteria using Diamine Oxidase and Leucocrystal Violet

1989 ◽  
Vol 52 (2) ◽  
pp. 105-108 ◽  
Author(s):  
SUSAN S. SUMNER ◽  
STEVE L. TAYLOR
Keyword(s):  
Hydrogen Peroxide ◽  
Liquid Culture ◽  
Diamine Oxidase ◽  
Culture Medium ◽  
Detection Method ◽  
Enzyme System ◽  
Color Formation ◽  
Liquid Culture Medium ◽  
Leucocrystal Violet ◽  
Purple Color

A detection method for histamine-producing, dairy-related bacteria was developed that involves a two-step sequential enzyme system. First, isolated bacteria are incubated in MRS broth or trypticase soy broth fortified with histidine. The histamine formed during this incubation period is reacted with diamine oxidase, which catalyzes the oxidation of histamine to form imidazole acetaldehyde, ammonia, and hydrogen peroxide. The hydrogen peroxide is then detected by the formation of crystal violet from the leuco base in the presence of horseradish peroxidase. Liquid culture medium containing bacteria that produce greater than 1200 nmole histamine per ml will develop a positive purple color. Cultures containing bacteria that produce little or no histamine will not develop a purple color. Other amines often found in cheese, such as tyramine, cadaverine, or putrescine, will not interfere with the color formation.

A PROCEDURE FOR RAPID RECOVERY OF AFLATOXINS FROM CHEESE AND OTHER FOODS1

1971 ◽  
Vol 34 (3) ◽  
pp. 119-123 ◽  
Author(s):  
C. N. Shih ◽  
E. H. Marth
Keyword(s):  
Liquid Culture ◽  
Culture Medium ◽  
Peanut Butter ◽  
Corn Meal ◽  
Water Fraction ◽  
Food Residue ◽  
Liquid Culture Medium ◽  
Chloroform Layer ◽  
Sequential Addition ◽  
Chloroform Methanol

A rapid and efficient method has been developed to recover aflatoxin from cheese and other foods. The procedure involves: (a) blending the sample with a mixture of chloroform, methanol, and water (solvents are used in such proportions that a miscible (monophasic) system is formed, (b) adding more chloroform and water so the mixture becomes biphasic, (c) filtering to remove the food residue, (d) separating the lower chloroform layer which contains virtually all of the aflatoxin, and (e) purification, if necessary, of the material in step (d) after it has been concentrated. Purification is achieved by sequential addition of methanol, water, and hexane; recovery of tho methanol-water fraction; and extraction of aflatoxins from it with chloroform. Purification can be eliminated if the substrate contains little or no lipid or pigment which, if present, interfere with thin-layer chromaographic analysis. Extraction can be done in approximately 35 min and purification in approximately 20 min. When aflatoxins were added to various substrates, the method recovered 92–98% B1 and 96–100% G1 from rice; 95–96% B1 and 90–95% G1 from peanut butter; 93–94% B1 and 92–98% G1 from Cheddar cheese; 100% B1 and G1 from corn meal; 91–100% B1, 91–100% B2, 90–96% G1, and 92–100% G2 from brick cheese; and 97–100% B1, 95–100% B2, 92–100% G1, and 98–100% G2 from a liquid culture medium.

Rapid analysis of GBSS1 and Vinv genes expressed in potato tubers using microtubers produced in liquid culture medium

2020 ◽  
Vol 39 (11) ◽  
pp. 1415-1424
Author(s):  
Yuhya Wakasa ◽  
Atsushi Kasai ◽  
Muneo Yamazaki ◽  
Yutaka Tabei ◽  
Mutsuo Tsuyama ◽  
...  
Keyword(s):  
Liquid Culture ◽  
Culture Medium ◽  
Rapid Analysis ◽  
Potato Tubers ◽  
Liquid Culture Medium

Accumulation and Conversion of Sugars by Developing Wheat Grains. I. Liquid Culture of Kernels Over Several Days

1981 ◽  
Vol 8 (6) ◽  
pp. 619 ◽  
Author(s):  
RM Gifford ◽  
PM Bremner
Keyword(s):  
Grain Growth ◽  
Liquid Culture ◽  
Sucrose Concentration ◽  
Starch Synthesis ◽  
Response Curves ◽  
Liquid Culture Medium ◽  
Net Uptake ◽  
Wheat Kernels ◽  
Substrate Concentrations

Wheat kernels, detached from the ear during the linear phase of grain growth and with their outer pericarps removed, took up sucrose from a liquid culture medium and sustained starch synthesis linearly for a week. Kernels cultured with their outer pericarps left on, but cut transversely in half, had more rapid starch synthesis initially but the rate was linear for only 3 days. The presence of the embryo was not necessary for the observed rates of starch synthesis. Rates of net uptake of sucrose into the kernels approximated rates of grain growth in vivo but only some was converted to starch, the rest remaining in an ethanol-soluble fraction. When the sucrose concentration in the medium was below about 300 mM, the concentration of 14C label (derived from [14C]sucrose), which had accumulated in the intracellular soluble pool after 3 days of culture, exceeded the concentration in the medium. Substrate response curves for starch synthesis showed an optimum at about 230 mM sucrose in the medium, declining at higher substrate concentrations. This optimum concentration approximated the sucrose concentration determined in the endosperm cavity directly after grain was taken from the plant.

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