The Experts below are selected from a list of 180 Experts worldwide ranked by ideXlab platform
María Gabriela Guevara - One of the best experts on this subject based on the ideXlab platform.
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Determination and characterisation of milk-clotting activity of two Solanum tuberosum aspartic proteases (StAPs)
International Dairy Journal, 2020Co-Authors: Florencia Rocío Tito, Alfonso Pepe, Claudia Virginia Tonon, Gustavo Raúl Daleo, María Gabriela GuevaraAbstract:Abstract To identify new coagulant enzymes as Rennet Substitutes, the aim of this study was to determine and to characterise the milk-clotting activity (MCA) of two potato aspartic proteases (StAPs). Both enzymes exhibited MCA in a dose-dependent manner. Optimum MCA values were determined at pH 5 and 30 °C. The ability of StAPs to degrade casein subunits was also evaluated. β-Casein was preferentially hydrolysed by both StAPs, followed by αS-casein and, to a lesser extent, κ-casein. These results confirmed the suitability of StAPs for producing curd and the possibility of using these proteases in artisanal cheese production.
Sridevi Annapurna Singh - One of the best experts on this subject based on the ideXlab platform.
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Production and characterization of a milk-clotting enzyme from Aspergillus oryzae MTCC 5341
Applied Microbiology and Biotechnology, 2010Co-Authors: Kurutahalli S. Vishwanatha, A. G. Appu Rao, Sridevi Annapurna SinghAbstract:Microbial milk-clotting enzymes are valued as calf Rennet Substitutes in the cheese industry. Aspergillus oryzae MTCC 5341 was identified to produce the highest milk-clotting activity during screening of 16 fungal strains. Solid state fermentation using wheat bran along with 4% defatted soy flour and 2% skim milk powder as substrate was optimal for growth of A. oryzae and production of the enzyme. Nearly 40,000 U/g bran of milk-clotting activity was present at the end of 120 h. The enzyme could be recovered by percolating the bran with 0.1 M sodium chloride for 60 min at 4°C. The decolorized enzyme preparation had high ratio of milk clotting to proteolytic activity. Affinity precipitation with alginate and subsequent elution with 0.5 M sodium chloride containing 0.2 M CaCl_2 resulted in an enzyme preparation with specific activity of 3,500 U/mg and 72% yield. Optimum pH and temperature for activity of the enzyme were characterized as 6.3 and 55°C, respectively. Milk-clotting enzyme showed differential degree of hydrolysis on casein components. High ratio of milk clotting to proteolytic activity coupled with low thermal stability strengthens the potential usefulness of milk-clotting enzyme of A. oryzae MTCC 5341 as a substitute for calf Rennet in cheese manufacturing.
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Production and characterization of a milk-clotting enzyme fromAspergillus oryzaeMTCC 5341
2010Co-Authors: G. Appu Rao, Sridevi Annapurna SinghAbstract:Microbial milk-clotting enzymes are valued as calf Rennet Substitutes in the cheese industry.Aspergillus oryzaeMTCC 5341 was identified to produce the highest milk-clotting activity during screening of 16 fungal strains. Solid state fermentation using wheat bran along with 4% defatted soy flour and 2% skim milk powder as substrate was optimal for growth ofA. oryzaeand production of the enzyme. Nearly 40,000 U/g bran of milk-clotting activity was present at the end of 120 h. The enzyme could be recovered by percolating the bran with 0.1 M sodium chloride for 60 min at 4°C. The decolorized enzyme preparation had high ratio of milk clotting to proteolytic activity. Affinity precipitation with alginate and subsequent elution with 0.5 M sodium chloride containing 0.2 M CaCl 2 resulted in an enzyme preparation with specific activity of 3,500 U/mg and 72% yield. Optimum pH and temperature for activity of the enzyme were characterized as 6.3 and 55°C, respectively. Milk-clotting enzyme showed differen- tial degree of hydrolysis on casein components. High ratio of milk clotting to proteolytic activity coupled with low thermal stability strengthens the potential usefulness of milk-clotting enzyme ofA. oryzaeMTCC 5341 as a substitute for calf Rennet in cheese manufacturing. KeywordsMicrobial Rennet . Aspergillus oryzae . Solidstatefermentation . Thermalstability . Immobilization . Casein components
Ing-lung Shih - One of the best experts on this subject based on the ideXlab platform.
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Milk-clotting enzymes produced by culture of Bacillus subtilis natto
Biochemical Engineering Journal, 2009Co-Authors: Chwen-jen Shieh, Lan-anh Phan Thi, Ing-lung ShihAbstract:Abstract Factors affecting the production of milk-clotting enzyme (MCE) by Bacillus subtilis (natto) Takahashi, a ready available commercial natto starter, were studied. Remarkable milk-clotting activity (MCA), 685.7 SU/ml or 12,000 SU/g, was obtained when the bacteria were cultivated in the medium containing sucrose (50 g/L) and basal salts at pH 6, 37 °C with shaking at 175 rpm for 1 day. The MCA and MCA/PA ratio of the crude enzyme obtained are comparable with those of Pfizer microbial rennin and Mucor rennin. The crude enzyme showed excellent pH and thermal stability; it retained 96% of MCA after incubation for 40 min at 40 °C and retained more than 80% of its activity between pH 4 and pH 7 for more than 30 min at 30 °C. The MCE of B. subtilis (natto) Takahashi has potential as calf Rennet Substitutes.
Kurutahalli S. Vishwanatha - One of the best experts on this subject based on the ideXlab platform.
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Production and characterization of a milk-clotting enzyme from Aspergillus oryzae MTCC 5341
Applied Microbiology and Biotechnology, 2010Co-Authors: Kurutahalli S. Vishwanatha, A. G. Appu Rao, Sridevi Annapurna SinghAbstract:Microbial milk-clotting enzymes are valued as calf Rennet Substitutes in the cheese industry. Aspergillus oryzae MTCC 5341 was identified to produce the highest milk-clotting activity during screening of 16 fungal strains. Solid state fermentation using wheat bran along with 4% defatted soy flour and 2% skim milk powder as substrate was optimal for growth of A. oryzae and production of the enzyme. Nearly 40,000 U/g bran of milk-clotting activity was present at the end of 120 h. The enzyme could be recovered by percolating the bran with 0.1 M sodium chloride for 60 min at 4°C. The decolorized enzyme preparation had high ratio of milk clotting to proteolytic activity. Affinity precipitation with alginate and subsequent elution with 0.5 M sodium chloride containing 0.2 M CaCl_2 resulted in an enzyme preparation with specific activity of 3,500 U/mg and 72% yield. Optimum pH and temperature for activity of the enzyme were characterized as 6.3 and 55°C, respectively. Milk-clotting enzyme showed differential degree of hydrolysis on casein components. High ratio of milk clotting to proteolytic activity coupled with low thermal stability strengthens the potential usefulness of milk-clotting enzyme of A. oryzae MTCC 5341 as a substitute for calf Rennet in cheese manufacturing.
Florencia Rocío Tito - One of the best experts on this subject based on the ideXlab platform.
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Determination and characterisation of milk-clotting activity of two Solanum tuberosum aspartic proteases (StAPs)
International Dairy Journal, 2020Co-Authors: Florencia Rocío Tito, Alfonso Pepe, Claudia Virginia Tonon, Gustavo Raúl Daleo, María Gabriela GuevaraAbstract:Abstract To identify new coagulant enzymes as Rennet Substitutes, the aim of this study was to determine and to characterise the milk-clotting activity (MCA) of two potato aspartic proteases (StAPs). Both enzymes exhibited MCA in a dose-dependent manner. Optimum MCA values were determined at pH 5 and 30 °C. The ability of StAPs to degrade casein subunits was also evaluated. β-Casein was preferentially hydrolysed by both StAPs, followed by αS-casein and, to a lesser extent, κ-casein. These results confirmed the suitability of StAPs for producing curd and the possibility of using these proteases in artisanal cheese production.