Thermal Destabilization of Rhizomucor miehei Rennet with Aldehyde Dextran Sulfate: Purification, Bioconjugation and Milk-Clotting Activities

2016 ◽  
Vol 180 (2) ◽  
pp. 261-273 ◽  
Author(s):  
Mithat Celebi ◽  
Murat Topuzogullari ◽  
Huriye Kuzu
Keyword(s):  
Dextran Sulfate ◽  
Rhizomucor Miehei ◽  
Milk Clotting

scholarly journals Study the influence of nitrogen on rennin production by fungi Rhizomucor miehei using solid-state fermentation

2016 ◽  
Vol 3 (5) ◽  
pp. 193
Author(s):  
Houthail Al-Ahmad Al-Jammas ◽  
Hassan Al-Fathi ◽  
Walid Al-Khalaf ◽  
Anton Taifor
Keyword(s):  
Enzyme Activity ◽  
Solid State ◽  
Protein Content ◽  
Yeast Extract ◽  
Wheat Bran ◽  
Solid State Fermentation ◽  
Rhizomucor Miehei ◽  
Milk Clotting ◽  
Milk Clotting Enzyme ◽  
Milk Clotting Activity

The effect of different nitrogen resources on the biosynthesis of milk clotting enzyme by Rhizmucor miehei was studied under solid state fermentation using wheat bran as base medium. Urea, peptone, albumin, casein, yeast extract were added with different concentrations (1%-10%). The response parameters were the ratio of milk clotting activity (MC) to proteolytic activity (PA) and protein content. The highest enzyme yield was achieved with casein at a rate of 2% w/w followed by 2% yeast extract, 1% albumin, 1% peptone, and 1% urea with values 5.6, 4.9, 4.2, 4, 3 mg/mL, respectively. Maximum enzyme activity (MCA/PA) was 50.4, 44.1, 37.8, 36, 27 SU for casein, yeast extract, albumin, peptone, and urea, respectively.

scholarly journals Influence of high pressure homogenization on commercial protease from Rhizomucor miehei: Effects on proteolytic and milk-clotting activities

LWT ◽  
2015 ◽  
Vol 63 (1) ◽  
pp. 739-744 ◽  
Author(s):  
Bruno Ricardo de Castro Leite Júnior ◽  
Alline Artigiani Lima Tribst ◽  
Marcelo Cristianini
Keyword(s):  
High Pressure ◽  
Rhizomucor Miehei ◽  
High Pressure Homogenization ◽  
Milk Clotting

scholarly journals Evaluation of the catalytic specificity, biochemical properties, and milk clotting abilities of an aspartic peptidase from Rhizomucor miehei

2016 ◽  
Vol 43 (8) ◽  
pp. 1059-1069 ◽  
Author(s):  
Ronivaldo Rodrigues da Silva ◽  
Tatiane Beltramini Souto ◽  
Tássio Brito de Oliveira ◽  
Lilian Caroline Gonçalves de Oliveira ◽  
Daniel Karcher ◽  
...  
Keyword(s):  
Rhizomucor Miehei ◽  
Biochemical Properties ◽  
Aspartic Peptidase ◽  
Milk Clotting

scholarly journals Characterization of a Novel Aspartic Protease from Rhizomucor miehei Expressed in Aspergillus niger and Its Application in Production of ACE-Inhibitory Peptides

Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2949
Author(s):  
Shounan Wang ◽  
Peng Zhang ◽  
Yibin Xue ◽  
Qiaojuan Yan ◽  
Xue Li ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Biochemical Characterization ◽  
Rhizomucor Miehei ◽  
Aspartic Protease ◽  
Protease Gene ◽  
Milk Clotting ◽  
Inhibitory Peptides ◽  
Ace Inhibitory Peptides ◽  
Ace Inhibitory

Rhizomucor miehei is an important fungus that produces aspartic proteases suitable for cheese processing. In this study, a novel aspartic protease gene (RmproB) was cloned from R. miehei CAU432 and expressed in Aspergillus niger. The amino acid sequence of RmproB shared the highest identity of 58.2% with the saccharopepsin PEP4 from Saccharomyces cerevisiae. High protease activity of 1242.2 U/mL was obtained through high density fermentation in 5 L fermentor. RmproB showed the optimal activity at pH 2.5 and 40 °C, respectively. It was stable within pH 1.5–6.5 and up to 45 °C. RmproB exhibited broad substrate specificity and had Km values of 3.16, 5.88, 5.43, and 1.56 mg/mL for casein, hemoglobin, myoglobin, and bovine serum albumin, respectively. RmproB also showed remarkable milk-clotting activity of 3894.1 SU/mg and identified the cleavage of Lys21-Ile22, Leu32-Ser33, Lys63-Pro64, Leu79-Ser80, Phe105-Met106, and Asp148-Ser149 bonds in κ-casein. Moreover, duck hemoglobin was hydrolyzed by RmproB to prepare angiotensin-I-converting enzyme (ACE) inhibitory peptides with high ACE-inhibitory activity (IC50 of 0.195 mg/mL). The duck hemoglobin peptides were further produced at kilo-scale with a yield of 62.5%. High-level expression and favorable biochemical characterization of RmproB make it a promising candidate for cheese processing and production of ACE-inhibitory peptides.

scholarly journals THE INFLUENCE OF MILK-CLOTTING ENZYMES ON THE FUNCTIONAL PROPERTIES OF PIZZA-CHEESES

Food systems ◽  
2020 ◽  
Vol 3 (3) ◽  
pp. 42-50
Author(s):  
D. S. Myagkonosov ◽  
V. A. Mordvinova ◽  
I. N. Delitskaya ◽  
D. V. Abramov ◽  
E. G. Ovchinnikova
Keyword(s):  
Moisture Content ◽  
Shelf Life ◽  
Proteolytic Activity ◽  
Functional Properties ◽  
Rhizomucor Miehei ◽  
High Dose ◽  
Low Level ◽  
Milk Clotting ◽  
Free Moisture ◽  
Milk Coagulation

The effect of the type and dose of milk-clotting enzymes (Chy-max® M based on recombinant camel chymosin, Fromase® TL based on Rhizomucor miehei protease) on the physicochemical, functional properties and shelf life of pizza-cheeses was studied. When using a low dose of milk-clotting enzymes (MCE) for milk coagulation (250–1100 IMCU per 100 kg of milk), cheeses were obtained with an increased moisture content (55–57%), excessive acidity (pH 4.8–4.9) and texture defects (incoherent, crumbly, with separation of free moisture). This is due to the formation of a weak curd, which releases moisture poorly during processing. The use of an increased dose of MCE makes it possible to obtain a denser curd, better releasing moisture. Cheese produced with a high dose of milk-clotting enzymes (2000–2800 IMCU per 100 kg of milk) had a lower moisture content (52–53%) and lower acidity (pH 5.0–5.1). The protein matrix is more hydrated in these cheeses, which ensures its better water holding capacity and a more homogeneous and cohesive texture. The use of an increased dose of MCE with a high total proteolytic activity (Fromase) gives undesirable consequences in the form of accelerated proteolysis of cheese mass proteins, rapid loss of functional properties of the cheese, and a decrease in the shelf life of cheese (less than 60 days). Cheese production using an increased dose of MCE with a low level of total proteolytic activity (Chy-max M) allows achieving a low level of proteolysis during cheese ripening and increasing its shelf life.

Thermal stability of acid proteinases

2000 ◽  
Vol 67 (4) ◽  
pp. 637-640 ◽  
Author(s):  
MARIE K. WALSH ◽  
XIAOSHAN LI
Keyword(s):  
Milk Fat ◽  
Thermal Inactivation ◽  
Three Dimensional ◽  
Skim Milk ◽  
Rhizomucor Miehei ◽  
Heat Stability ◽  
Cryphonectria Parasitica ◽  
Maximum Activity ◽  
Enzyme Preparations ◽  
Milk Clotting

Milk-clotting enzymes are used during the production of cheese to coagulate the casein, allowing the formation of a three-dimensional network that entraps the milk fat. Commercially available milk-clotting enzymes differ with respect to source, specificity, optimum pH and thermostability. All are acid proteinases that can cleave κ-casein resulting in the coagulation of milk. Chymosin (EC 3.4.23.4) is specific for the Phe–Met bond in κ-casein at the natural pH of milk (6·7). Recombinant chymosin is available commercially from a variety of sources and has a maximum activity at 40 °C. Recombinant chymosins are purified from the fermentation of recombinant strains of Aspergillus niger, Asp. oryzae or Kluyveromyces marxianus. These enzyme preparations are chemically and functionally identical to calf chymosin. Rennets are purified from the abomasum of bovines and can contain from 60 to 100% chymosin with the remainder being primarily bovine pepsin (Wigley, 1996). Microbial proteinases (EC 3.4.23.6) are generally more proteolytic than chymosin, with varying heat stability. These enzymes liberate more non-protein N from casein and can cleave α- and β-casein as well as κ-casein at the natural pH of milk. Acid proteinases from Cryphonectria parasitica are more heat labile than those from Rhizomucor miehei, which are characterized as thermostable (Ernstrom & Wong, 1974).The objective of this research was to characterize milk-clotting enzymes with respect to thermal inactivation in skim milk. This information has applications in milk and whey processing.

scholarly journals Influence of different milk-coating enzymes on the process of producing soft cheeses

Food systems ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 204-212
Author(s):  
D. S. Myagkonosov ◽  
I. T. Smykov ◽  
D. V. Abramov ◽  
I. N. Delitskaya ◽  
V. N. Krayushkina
Keyword(s):  
Rhizomucor Miehei ◽  
Cost Effective ◽  
Milk Clotting ◽  
Microbial Origin ◽  
Dry Matter Loss ◽  
Milk Clotting Enzyme ◽  
Negative Effect ◽  
Milk Coagulation ◽  
Ph Level ◽  
Different Origins

The effect of the type of milk clotting enzyme (MCE) on the duration of milk coagulation, parameters of the composition of whey and cheeses, and the output of cheeses in the production of soft cheese such as “Lyubitel'skiy” were investigated. Three brands of MCE of different origins were investigated: Marzyme® (MCE of microbial origin based on Rhizomucor miehei protease), Naturen® (calf rennet) and Chy-max® M (recombinant camel chymosin). It was established that MCEs had different ratios of milk clotting activity (MCA) to total proteolytic activity (PA). It was determined that the MCA/PA ratio, which characterizes the degree of specificity of the MCE action with regard to kappa-casein, in Chy-max M 1000 is ~7 times higher than that of Naturen and ~50 times higher than that of Marzyme. Such differences did not lead to a negative effect when using the Marzyme preparation in the production of soft cheeses. There were no statistically significant differences in the amount of dry matter loss of the curd into the whey, physicochemical parameters and output between the variants of cheeses made with the studied brands of MCE. Shorter duration of milk clotting (16.5 min) was observed with Marzyme than with MCE of Naturen (20.5 min) and Chy-max M (22.5 min). The results of the coagulation duration were explained by the stimulation of the activity of MCE of microbial origin, by the pH level of milk before coagulation (below pH 6.4). It was shown that modern MCEs of microbial origin could be recommended as a cost-effective replacement for more expensive rennet and recombinant chymosins in the production of soft and fresh cheeses.

The Effect of Dietary Glutathione and Coenzyme Q10 on the Prevention and Treatment of Inflammatory Bowel Disease in Mice

2004 ◽  
Vol 74 (1) ◽  
pp. 74-85 ◽  
Author(s):  
Liu ◽  
Russell ◽  
Smith ◽  
Bronson ◽  
Milbury ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Bowel Disease ◽  
Dextran Sulfate ◽  
Coenzyme Q ◽  
Histological Evaluation ◽  
Therapeutic Effects ◽  
Prevention Study ◽  
Prevention And Treatment ◽  
Inflammatory Bowel ◽  
Pre Treatment

Because reactive oxygen species have been implicated as mediators of inflammatory bowel disease (IBD), we evaluated the potential preventive and therapeutic effects of two dietary antioxidants, glutathione (GSH) and coenzyme Q10 (CoQ10) on dextran sulfate sodium (DSS)-induced colitis in mice. Fifty female 8-wk old Swiss-Webster mice were randomly assigned to 4 groups for a pre-treatment 'prevention' study: (1) GSH (1% of diet); (2) CoQ10 (200 mg/kg/d); (3) DSS only (3% of drinking water); (4) control (no treatment). The mice in groups 1 and 2 were fed with GSH or CoQ10 for 21 wks, and the mice in groups 1, 2 and 3 were provided DSS from wk 7 for 4 cycles (1 cycle = 1 wk DSS followed by 2-wk water). Another 50 mice were randomly assigned to 4 groups for a 21-wk 'treatment' study where the mice in groups 1, 2, and 3 were administered DSS for 6 cycles (18 wks) to induce colitis. GSH and CoQ10 were added from wk 7 until the completion of the protocol. Loose stools and hemocult positivity were modestly but significantly reduced with GSH or CoQ10 at several periods during the intervention in both the prevention and treatment studies. In contrast, histological evaluation revealed increases in colonic dysplasia and ulceration with GSH or CoQ10. Thus, in this mouse model, GSH and CoQ10 appear to have a beneficial effect on acute signs of IBD, but may have an adverse impact on the chronic pathophysiology of the disease. Further studies using additional animal models are required to determine whether GSH or CoQ10 provide a favorable or unfavorable benefit:risk ratio in the prevention or treatment of IBD.

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