Impact of gastric pH on dietary enzyme activity and survivability in swine fed β-glucanase supplemented diets

1996 ◽  
Vol 76 (2) ◽  
pp. 245-252 ◽  
Author(s):  
T. C. Baas ◽  
P. A. Thacker
Keyword(s):  
Enzyme Activity ◽  
Latin Square ◽  
Gastric Ph ◽  
Glucanase Activity ◽  
Enzyme Preparations ◽  
Optimum Ph ◽  
Deterioration Effect ◽  
Series Of Experiments ◽  
Ph Level ◽  
Daily Gain

A series of experiments was conducted to determine the effect of pH on β-glucanase activity and to monitor the effect of passage through the stomach on the ability of enzymes to degrade β-glucans. In exp. 1, β-glucanase activity was determined in 10 commercially available enzyme products at 5 pH levels (2.5, 3.5, 4.5, 5.5 and 6.5) using a discontinuous assay. Little activity was evident at pH 2.5, and activity was only slightly increased at pH 3.5. The highest activity occurred at pH 4.5 and 5.5. Enzyme activity declined quickly at pH 6.5. Experiment 2 evaluated the capability of β-glucanase to recover activity after incubation at suboptimal pH levels. Five enzyme preparations were incubated at three pH levels (2.5, 3.5 and 4.5) for 15, 30, 60 or 120-min. The pH level was then increased to pH 5.5, which was the optimum pH for activity determined in exp. 1. All enzyme products were relatively stable at pH 4.5 and 5.5. Enzyme products treated at pH 3.5 started to lose activity and all enzyme products exhibited a deterioration effect when incubated at pH 2.5. However, all enzymes recovered some activity upon return to pH 5.5. Experiment 3 was designed to evaluate the amount of β-glucanase activity leaving the stomach of the pig. Six barrows cannulated with a simple T-cannulae located at the start of the duodenum were used in a 6 × 6 Latin square design experiment. The diets consisted of a control and five diets supplemented with the same enzymes used in exp. 2. The level of β-glucanase activity in the digesta from pigs fed any of the diets decreased over time as pH decreased. However, across all products, 52 and 26% of initial activity could still be detected 60 and 240 min after feeding. Experiment 4 was conducted to evaluate the effectiveness of the five enzyme sources in improving the performance of pigs fed hulless barley-based diets. Supplementation of hog growing-finishing rations with any of the enzyme products failed to significantly (P > 0.05) improve daily gain, feed intake or feed efficiency. The digestibility coefficients for dry matter, crude protein and energy showed a general trend towards improved digestibility with enzyme supplementation (P > 0.05) with Biofeed producing a significant increase. The overall results of these experiments indicate that although the low pH found in the stomach of the pig is detrimental to enzyme activity, some enzyme activity is retained in the small intestine of the pig. Therefore, the low gastric pH of the pig and its effects on enzyme activity cannot completely explain the lack of response of pigs to β-glucanase. Key words: β-glucanase, pH, pig, enzyme

Synthesis of β-glucan by cell-free extracts of Aureobasidium pullulans

1987 ◽  
Vol 33 (2) ◽  
pp. 123-127 ◽  
Author(s):  
Malcolm A. J. Finkelman ◽  
Alex Vardanis
Keyword(s):  
Enzyme Activity ◽  
Acetic Acid ◽  
Bovine Serum Albumin ◽  
Aureobasidium Pullulans ◽  
Enzyme Preparation ◽  
Glucanase Activity ◽  
Free System ◽  
Enzyme Preparations ◽  
Partial Activation ◽  
A Cell

A cell-free system catalysing the synthesis of β-glucan from uridine-diphosphoglucose was prepared from Aureobasidium pullulans. The activity was stable in the presence of 1 M sucrose and 10 mM MgSO4. The polymer produced was insoluble in H2O or acetic acid (0.5 M) and soluble in NaOH (0.5 M). Several enzyme preparations containing β-glucanase activity degraded the polymer to various extents. Synthesis of the polymer was enhanced by the presence of cellobiose and bovine serum albumin, but not by NaF or ATP. A Lineweaver–Burke plot of enzyme activity versus substrate concentration revealed biphasic kinetics. The enzyme preparation was subject to partial activation by trypsin and chymotrypsin.

Proteolytic enzymes produced in liquid media by Fusiformis nodosus

1964 ◽  
Vol 15 (3) ◽  
pp. 417 ◽  
Author(s):  
JH Thomas
Keyword(s):  
Enzyme Activity ◽  
Stationary Phase ◽  
Proteolytic Enzymes ◽  
Logarithmic Phase ◽  
Liquid Media ◽  
Enzyme Preparations ◽  
Stages Of Growth ◽  
Optimum Ph ◽  
Digestive Activity ◽  
Sulphydryl Compounds

Four strains of Fusiformis nodosus examined were shown to produce proteolytic enzymes digesting azocasein. When enzyme activity was plotted against the age of culture, the curves obtained showed two maxima, the first coinciding with the end of the logarithmic phase of growth, and the second with the end of the stationary phase. Enzyme preparations obtained at either of these stages of growth had similar properties, and digested casein and haemoglobin. The addition of sulphydryl compounds was without effect on the casein-digestive activity of either preparation, but enhanced the digestion of haemoglobin. The optimum pH for casein digestion by either preparation was about 9.5. Both preparations had similar stability to treatment by acid or alkali and both were inactivated by exposure to temperatures greater than 50°C.

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.

Effect of temperature and pH on the production, activity, and stability of α-amylase from Bacillus subtilis V37

2021 ◽  
Vol 66 (1) ◽  
pp. 72-79
Author(s):  
Thuoc Doan Van ◽  
Hung Nguyen Phuc
Keyword(s):  
Enzyme Activity ◽  
Bacillus Subtilis ◽  
Animal Feed ◽  
Culture Conditions ◽  
Effect Of Temperature ◽  
Physical Parameters ◽  
Original Activity ◽  
Optimum Ph ◽  
Production Activity ◽  
Ph Range

The effect of physical parameters such as temperature and pH on the production, activity, and stability of α-amylase from Bacillus subtilis V37 was investigated. The results indicated that the optimum culture conditions for enzyme activity were pH 7.0 and 35 oC. The optimum pH and temperature for enzyme activity were 6.0 and 70 oC. The crude enzyme was found to be stable in the pH range of 5.0 to 7.0. The enzyme was stable for 1 h at a temperature from 30 to 80 oC; nearly 100% of enzyme activity remained at temperatures of 30 - 40 oC, and about 34% of original activity remained at a temperature of 80 oC. These features demonstrated that α-amylase from B. subtilis V37 can be applied in many areas such as the food, fermentation, and animal feed industries.

β-GLUCURONIDASE OF RABBIT POLYMORPHONUCLEAR LEUCOCYTES

1950 ◽  
Vol 28e (3) ◽  
pp. 69-79 ◽  
Author(s):  
R. J. Rossiter ◽  
Esther Wong
Keyword(s):  
Enzyme Activity ◽  
Blood Plasma ◽  
Substrate Concentration ◽  
Final Concentration ◽  
White Cell ◽  
Polymorphonuclear Leucocytes ◽  
Michaelis Constant ◽  
Glucuronidase Activity ◽  
Arsanilic Acid ◽  
Optimum Ph

Rabbit polymorphonuclear leucocytes contain an enzyme capable of hydrolyzing biosynthetic phenolphthalein mono-β-glucuronide. The concentration of the enzyme in the white cell is some 2000 times the concentration of the enzyme in the blood plasma. Under the conditions of study, the β-glucuronidase activity was proportional to the concentration of the enzyme. The effect of substrate concentration on the enzyme activity was studied and the Michaelis constant, Ks, determined. The course of the reaction was linear with time for the first 12 hr. and then fell off slightly during the next 12 hr. The optimum pH of the enzyme was 4.45 in either 0.2 M acetate or 0.2 M phthalate buffer. It was not inhibited by cyanide, azide, iodoacetate, fluoride, glycine, thiourea, urethane, arsanilic acid, acetophenone, o-cresol or m-cresol, in a final concentration of 0.01 M. The possible function of β-glucuronidase in rabbit polymorphonuclear leucocytes is discussed.

scholarly journals Lignolytic Enzyme Activity of Isolated Bacteria from Termite (Coptotermes Sp.) and Milkfish (Chanos chanos Forsskal, 1775) Guts

2021 ◽  
Vol 13 (1) ◽  
pp. 70-76
Author(s):  
Emi Latifah ◽  
Putri Dwi Mulyani ◽  
Yekti Asih Purwestri
Keyword(s):  
Enzyme Activity ◽  
Bacillus Licheniformis ◽  
Test Method ◽  
Chanos Chanos ◽  
Enzyme Isolation ◽  
Optimum Ph ◽  
Qualitative Test ◽  
Pseudomonas Alcaligenes ◽  
Enzyme Source ◽  
Brevibacillus Parabrevis

Bacteria BSR 2, Pseudomonas alcaligenes (BSR 3), Brevibacillus parabrevis (BSR 8), Brevibacillus sp. (BSR 9), isolated from termite gut and Bacillus licheniformis (BSA B1) isolated from milkfish gut have been known to possess celluloytic activity. However, their lignolytic ability has not been known. This study aimed to determine the lignolytic ability of bacteria isolated from termit (Coptotermes sp.) and milkfish (Chanos chanos Forsskal, 1775) guts and their enzymes characterization. The qualitative test was done through the spot test method, while quantitative assay was performed spectrophotometrically at 335 nm to calculate vanillin concentration. The isolates were grown in Lignin Mineral Medium, then the optical density (OD620) were measured every 24 hours for 5 days using spectrophotometer to determine their growth profile and the best isolation time of the lignolytic enzyme. Based on results, the best lignolytic enzyme isolation time for strains Bacillus licheniformis (BSA B1) and BSR 2 were 5 days, yielding lignolytic enzyme activity of 0.961 ± 0.168 U/mg and 2.176 ± 0.088 U/mg respectively,  while strains Pseudomonas alcaligenes (BSR 3), Brevibacillus parabrevis (BSR 8), and Brevibacillus sp. (BSR 9) were 4 days, yielding of 1.206 ± 0.045 U/mg, 1.162 ± 0.191 U/mg, and 0.896 ± 0.108 U/mg, respectively. The strain BSR 2 showed the highest lignolytic activity compared to other strains. The optimum temperature for lignolytic enzyme activity of BSR 2 was 30 ℃ and the optimum pH was 7. The lignolytic enzyme activity showed that these bacterial isolates can be a chance to be used as new alternative lignolytic enzyme source in commercial bioconversion process.

scholarly journals Pre-fermentative treatment of a model wine with aim to serve as a functional food with decreased alcohol content

2017 ◽  
Vol 63 (01) ◽  
pp. 47-53
Author(s):  
Irina Mladenoska ◽  
Verica Petkova ◽  
Tatjana Kadifkova Panovska
Keyword(s):  
Enzyme Activity ◽  
Gluconic Acid ◽  
Functional Food ◽  
Ph Value ◽  
Enzymatic Reaction ◽  
Alginate Beads ◽  
High Concentration ◽  
Ph Optimum ◽  
Enzyme Preparations ◽  
Initial Ph

The effect of substrate concentration on the enzyme activity in the reaction of glucose conversion into gluconic acid was investigated by using three different enzyme preparations in media with two different glucose concentrations. The media were simulating the conditions in the must, thus named as minimal model must, and were composed form combination of several organic acids and glucose. Those media were having initial pH of 3.5 that is a very unfavorable for glucose oxidase activity having a pH optimum at the pH value of 5.5. Among the three preparations used, the bakery additive, Alphamalt Gloxy 5080, was the most active in the medium with glucose concentration of 10 g/L, showing conversion of more than 70% for the period of 24 h, while the same enzyme preparation in the medium with 100 g/L glucose converted only about 7% of glucose. The pH value of the medium at the beginning and at the end of the enzymatic reaction was a good indicator of the enzyme activity. It seems that for the conversion of glucose in higher concentration, enzymatic preparation in high concentration should also be used. The preliminary attempt of immobilization of two preparations of glucose oxidases in alginate beads was also performed and a successful immobilization procedure for utilization in food industry was preliminarily developed. Keywords: glucose oxidases, enzymatic pretreatment, glucose, gluconic acid, model wine, functional food

scholarly journals Studies on the production of glucose isomerase by Bacillus licheniformis

2015 ◽  
Vol 17 (3) ◽  
pp. 84-88 ◽  
Author(s):  
Ogbonnaya Nwokoro
Keyword(s):  
Enzyme Activity ◽  
Bacillus Licheniformis ◽  
Organic Nitrogen ◽  
Specific Activity ◽  
Inorganic Nitrogen ◽  
Glucose Isomerase ◽  
Culture Conditions ◽  
Enzyme Productivity ◽  
Carbon Substrates ◽  
Optimum Ph

Abstract This work reports the effects of some culture conditions on the production of glucose isomerase by Bacillus licheniformis. The bacterium was selected based on the release of 3.62 mg/mL fructose from the fermentation of glucose. Enzyme was produced using a variety of carbon substrates but the highest enzyme activity was detected in a medium containing 0.5% xylose and 1% glycerol (specific activity = 6.88 U/mg protein). Media containing only xylose or glucose gave lower enzyme productivies (specific activities= 4.60 and 2.35 U/mg protein respectively). The effects of nitrogen substrates on glucose isomerase production showed that yeast extract supported maximum enzyme activity (specific activity = 5.24 U/mg protein). Lowest enzyme activity was observed with sodium trioxonitrate (specific activity = 2.44 U/mg protein). In general, organic nitrogen substrates supported higher enzyme productivity than inorganic nitrogen substrates. Best enzyme activity was observed in the presence of Mg2+ (specific activity = 6.85 U/mg protein) while Hg2+ was inhibitory (specific activity = 1.02 U/mg protein). The optimum pH for best enzyme activity was 6.0 while optimum temperature for enzyme production was 50ºC.

Studies on the effect of some drugs on the gastric pH level

1969 ◽  
Vol 4 (3) ◽  
pp. 196-196
Author(s):  
T. Shibuya ◽  
T. Hino ◽  
Y. Saito ◽  
S. Abe ◽  
T. Sekino
Keyword(s):  
Gastric Ph ◽  
Ph Level

Effects of pantothenic acid and folic acid supplementation on total tract digestibility coefficient, ruminal fermentation, microbial enzyme activity, microflora and urinary purine derivatives in dairy bulls

2019 ◽  
Vol 157 (6) ◽  
pp. 555-562
Author(s):  
Z. Z. Wu ◽  
C. Wang ◽  
G. W. Zhang ◽  
Q. Liu ◽  
G. Guo ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Folic Acid ◽  
Average Daily Gain ◽  
Pantothenic Acid ◽  
Latin Square ◽  
Ammonia Nitrogen ◽  
Ruminal Fermentation ◽  
Feed Conversion ◽  
Purine Derivative ◽  
Dairy Bulls

AbstractThe effects of pantothenic acid (PA) and folic acid (FA) addition on digestibility coefficient, ruminal fermentation and urinary purine derivative (PD) excretion in dairy bulls were evaluated. Eight rumen-cannulated Holstein dairy bulls were allocated to a replicated 4 × 4 Latin square design according to a 2 × 2 factorial arrangement. Diets were supplemented with two levels of FA (0 or 8.0 mg/kg dietary dry matter [DM]) and two of PA (0 or 60 mg/kg DM). The PA × FA interaction was not significant for all variables. Both supplements increased DM intake and average daily gain, but decreased a feed conversion ratio. Digestibility of DM, organic matter, crude protein and neutral detergent fibre increased, but ether extract digestibility was unchanged for both supplements. Digestibility of acid detergent fibre only increased with FA supplementation. For both supplements, ruminal pH and ammonia nitrogen (N) decreased, but total volatile fatty acid (VFA) concentration increased. Acetate proportion only increased with FA supplementation. Propionate proportion decreased for both supplements. Consequently, the acetate to propionate ratio increased. For both supplements, activity of xylanase and pectinase, population of Ruminococcus albus, R. flavefaciens, Fibrobacter succinogenes and Ruminobacter amylophilus and total PD excretion increased. Additionally, activity of carboxymethylcellulase, cellobiase, α-amylase and protease, and population of total bacteria, fungi, protozoa, methanogens, Butyrivibrio fibrisolvens and Prevotella ruminicola increased with FA addition. The results suggested that PA and FA supplementation stimulated ruminal microbial growth and enzyme activity, resulting in an increased digestibility coefficient and ruminal total VFA concentration in dairy bulls.

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