Cheese-making Ability of Plumeria alba and Plumeria rubra Latex: Milk Clotting and Proteolytic Activities
Ibidjokè Rachidatou Bankole,
Seid Ali Mahamat,
Mouaïmine Mazou,
Sênan Christa Marie Josephine Lokossou,
Fidèle Paul Tchobo
Issue:
Volume 9, Issue 3, May 2021
Pages:
47-52
Received:
20 April 2021
Accepted:
28 May 2021
Published:
15 June 2021
Abstract: In cheese making industry, plant enzymes are used to produce cheese. In Ouest Africa, they produced the cheese “waragashi” with the mix milk and the plant Calotropis procera. The objective of our study is to assess ability to coagulate milk of the latex from news plants Plumeria alba and Plumeria rubra. If the two plants can supplied Calotropis procera in cheese making. For the results, we observed that the latex of Plumeria alba and Plumeria rubra are richer in proteins and mineral elements than the latex of Calotropis procera. It appears that the milk clotting and proteolytic activities of the latex of Plumeria alba and Plumeria rubra reached their optimum at 75°C while those of Calotropis procera reached the optimum at 55°C but remained active above 60 and 70°C. The Proteolytic Activity of the latex of C. procera and the two species of Plumeria was maximal at concentrations of 10% and 20% in the reaction medium, respectively. Polyacrylamide gel electrophoresis revealed that Plumeria alba latex had proteins with molecular weights of 10 and 25 kDa while the molecular weights Plumeria rubra latex proteins were 10, 25, 45kDa. The MCA/ PA ratio of Calotropis procera, Plumeria alba and Plumeria rubra was 1142.86; 810.81 and 576.92 respectively. These two Plumeria latex could validly replace C. procera latex in the production of cheese.
Abstract: In cheese making industry, plant enzymes are used to produce cheese. In Ouest Africa, they produced the cheese “waragashi” with the mix milk and the plant Calotropis procera. The objective of our study is to assess ability to coagulate milk of the latex from news plants Plumeria alba and Plumeria rubra. If the two plants can supplied Calotropis pro...
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CO2 Valorization Reactions over Cu-Based Catalysts: Characterization and the Nature of Active Sites
Ubong Jerome Etim,
Raphael Semiat,
Ziyi Zhong
Issue:
Volume 9, Issue 3, May 2021
Pages:
53-78
Received:
25 May 2021
Accepted:
7 June 2021
Published:
21 June 2021
Abstract: Active sites are the individual reactors at the molecular scale distributed on the heterogeneous catalyst surface. To a large extent, they determine the catalytic performances and the reaction pathway of a reaction. Therefore, understanding the nature and structure of the actives sites is crucial to improve and develop novel, robust and practical catalysts. The wide application of state-of-the-art characterization techniques these years makes it possible to obtain crucial information about the active sites for some catalysts. The Cu-based catalysts are widely used for water gas shift (WGS) and methanol synthesis from syngas (CO + H2). Although having some technical issues in the direct conversion of CO2 into value-added products, they are still promising for this reaction to mitigate CO2 concentration in the atmosphere. In the last several years, intensive efforts have been made to study Cu-based catalysts, and substantial progress has been achieved in understanding their active sites and the reaction mechanism. This review discusses the structure and nature of active sites of Cu-based catalysts for CO2 valorization in thermo-, photo-, and electro-catalysis. We present the characterization results of different types of Cu-based catalysts applied in these processes, unravel their active sites and structures, and figure out the most important and critical factors that drive the reactions on the sites. The principle and applications of various characterization techniques are also briefly analyzed and compared. It is expected to provide fundamental insights and perspectives for designing highly active and efficient catalysts for CO2 conversion.
Abstract: Active sites are the individual reactors at the molecular scale distributed on the heterogeneous catalyst surface. To a large extent, they determine the catalytic performances and the reaction pathway of a reaction. Therefore, understanding the nature and structure of the actives sites is crucial to improve and develop novel, robust and practical c...
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