scholarly journals Milk peptides; effect on the enzymatic hydrolysis of sodium caseinate

1993 ◽  
Vol 2 (5) ◽  
pp. 371-378
Author(s):  
Zahur U. Haque ◽  
Pirkko Antila
Keyword(s):  
Enzyme Activity ◽  
Enzymatic Hydrolysis ◽  
Sodium Caseinate ◽  
Precipitation Method ◽  
Sweet Whey ◽  
Milk Peptides ◽  
Hydrolysis Of ◽  
Peptide Fractions ◽  
Different Levels

Sodium caseinate (NaCN) was hydrolyzed using Rhozyme 41 (Rh41), Neutrase (Neu) and plasmin (PL) to obtain peptide preparations termed; Na-Cas-P-Rh41, Na-Cas-P-Neu, and Na-Cas-P-Plasmin, respectively. Indigenous whey peptides (IWP) were obtained from fresh sweet whey, at different levels of ufconcentration, by a precipitation method described earlier. These peptide fractions were then used to observe their effect on the activity of some proteases. All peptide preparations depressed enzyme activity. Na-Cas-P-Rh41 was the most powerful inhibitor of enzyme activity and decreased the activity of trypsin, Rh41, Neu. and PL by 15, 32, 50, and 14%, respectively. IWP markedly depressed activity of Rh41. The degree of uf-concentration of whey from which IWP was obtained was directly related to degree of inhibition.

Production of Interesting Peptide Fractions by Enzymatic Hydrolysis of Tuna Dark Muscle By-Product Using Alcalase

2014 ◽  
Vol 25 (2) ◽  
pp. 251-264 ◽  
Author(s):  
Sami Saidi ◽  
Marie-Pierre Belleville ◽  
André Deratani ◽  
Raja Ben Amar
Keyword(s):  
Enzymatic Hydrolysis ◽  
Dark Muscle ◽  
Hydrolysis Of ◽  
Peptide Fractions

Characteristics of Enzymatic Hydrolysis of the Wheat Gluten Proteins Treated by Ultrasound Wave

2011 ◽  
Vol 343-344 ◽  
pp. 1015-1022
Author(s):  
Hua Li Jin ◽  
Jin Shui Wang ◽  
Ke Bian
Keyword(s):  
Enzymatic Hydrolysis ◽  
Power Output ◽  
Wheat Gluten ◽  
Protein Recovery ◽  
Degree Of Hydrolysis ◽  
Ultrasound Wave ◽  
Gluten Proteins ◽  
Hydrolysis Of ◽  
Peptide Fractions ◽  
Large Peptide

Effects of sonication at 150W and 300W power output on hydrolysis of wheat gluten using two proteinases (Protamex and papain) were evaluated in the present study. Sonication resulted in the increase in amounts of free sulphydryl (SH) of wheat gluten. Significant (P < 0.05) increase in SH contents at 300W power output was found compared with the control and those samples sonicated at 150W power output. Degree of hydrolysis (DH) and protein recovery (PR) of the wheat gluten hydrolysates increased with sonication time and power output. Significant (P < 0.05) increase in DH and PR of the wheat gluten hydrolysate from the sample sonicated by 300W power output was found compared to those sonicated by 150W output. Sonication caused the decrease in the relative percent of the large peptide fractions and increase in the relative percent of the small peptide fractions in the hydrolysates compared to the control. Structure change in insoluble wheat gluten proteins was the principal reason of improvement in their characteristics of enzymatic hydrolysis.

Rapid detection of coliform bacteria and influence of non-target bacteria

1997 ◽  
Vol 35 (11-12) ◽  
pp. 415-418 ◽  
Author(s):  
L. Fiksdal ◽  
I. Tryland ◽  
H. Nelis
Keyword(s):  
Water Pollution ◽  
Enzyme Activity ◽  
Enzymatic Hydrolysis ◽  
Rapid Detection ◽  
Coliform Bacteria ◽  
Sewage Effluent ◽  
Fluorogenic Substrates ◽  
Polluted River ◽  
Thermotolerant Coliforms ◽  
Hydrolysis Of

Enzymatic hydrolysis of fluorogenic substrates (4-methylumbelliferyl-β-D-galactoside, 4-methylumbelliferyl-β-D-glucuronide) has been used for rapid (25min) detection of indicators of faecal water pollution, i.e. coliform and thermotolerant coliform bacteria. In the present work, enzymatic activities and different groups of bacteria (i.e. thermotolerant coliforms, coliforms, β-galactosidase positive and β-glucuronidase positive bacteria) from sewage effluent and polluted river water have been investigated. Ratios of the order of 1:10 between coliforms and β-galactosidase positive bacteria were demonstrated. The contribution from β-galactosidase positive non-coliform bacteria to the measured enzyme activity should not, therefore, be neglected. Numbers of β-glucuronidase positive non-coliforms indicate interference of this group in the rapid assay.

scholarly journals THF co-solvent pretreatment prevents lignin redeposition from interfering with enzymes yielding prolonged cellulase activity

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Abhishek S. Patri ◽  
Ramya Mohan ◽  
Yunqiao Pu ◽  
Chang G. Yoo ◽  
Arthur J. Ragauskas ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Sulfuric Acid ◽  
Enzymatic Hydrolysis ◽  
Cellulase Activity ◽  
Biofuel Production ◽  
Scanning Electron Micrographs ◽  
Enzyme Deactivation ◽  
Dilute Sulfuric Acid ◽  
Nmr Characterization ◽  
Hydrolysis Of

Abstract Background Conventional aqueous dilute sulfuric acid (DSA) pretreatment of lignocellulosic biomass facilitates hemicellulose solubilization and can improve subsequent enzymatic digestibility of cellulose to fermentable glucose. However, much of the lignin after DSA pretreatment either remains intact within the cell wall or readily redeposits back onto the biomass surface. This redeposited lignin has been shown to reduce enzyme activity and contribute to rapid enzyme deactivation, thus, necessitating significantly higher enzyme loadings than deemed economical for biofuel production from biomass. Results In this study, we demonstrate how detrimental lignin redeposition on biomass surface after pretreatment can be prevented by employing Co-solvent Enhanced Lignocellulosic Fractionation (CELF) pretreatment that uses THF–water co-solvents with dilute sulfuric acid to solubilize lignin and overcome limitations of DSA pretreatment. We first find that enzymatic hydrolysis of CELF-pretreated switchgrass can sustain a high enzyme activity over incubation periods as long as 5 weeks with enzyme doses as low as 2 mg protein/g glucan to achieve 90% yield to glucose. A modified Ninhydrin-based protein assay revealed that the free-enzyme concentration in the hydrolysate liquor, related to enzyme activity, remained unchanged over long hydrolysis times. DSA-pretreated switchgrass, by contrast, had a 40% drop in free enzymes in solution during incubation, providing evidence of enzyme deactivation. Furthermore, measurements of enzyme adsorption per gram of lignin suggested that CELF prevented lignin redeposition onto the biomass surface, and the little lignin left in the solids was mostly integral to the original lignin–carbohydrate complex (LCC). Scanning electron micrographs and NMR characterization of lignin supported this observation. Conclusions Enzymatic hydrolysis of solids from CELF pretreatment of switchgrass at low enzyme loadings was sustained for considerably longer times and reached higher conversions than for DSA solids. Analysis of solids following pretreatment and enzymatic hydrolysis showed that prolonged cellulase activity could be attributed to the limited lignin redeposition on the biomass surface making more enzymes available for hydrolysis of more accessible glucan.

scholarly journals BIOTECHNOLOGY OF OBTAINING A HYDROLYTIC ENZYMATIC AGENT WITH α-D- GALACTOSIDASE ACTIVITY

2016 ◽  
Vol 10 (3) ◽  
Author(s):  
А. Petrosyants
Keyword(s):  
Enzyme Activity ◽  
Enzymatic Hydrolysis ◽  
Galactosidase Activity ◽  
Optimal Parameters ◽  
Hydrolysis Of

The studies referred to in this article showed the principle possibility of use of hydrolytic enzymatic agentwith α-D-galactosidase activity for the enzymatic hydrolysis of soy oligosaccharides. Optimal parameters of the enzyme activitywere determined (pH, temperature). It was shown that the use of various techniques of purification and concentrating of theenzyme preparation allows increasing of the activity of the agent 5.5 times. Enzyme activity was determined.

Sign in / Sign up

Export Citation Format

Share Document