scholarly journals Enzyme Unit

2020 ◽  
Author(s):  
Keyword(s):  
2020 ◽  
Vol 2020 ◽  
pp. 1-7 ◽  
Author(s):  
Huseyin Sahin ◽  
Sevgi Kolayli ◽  
Mehmet Beykaya

Invertase and glucose oxidase are secreted by the hypopharyngeal glands of honeybees for the hydrolysis of sucrose and the preservation from microbial effects, respectively. It is also prominent to understand how the levels of invertase and glucose oxidase of raw honey samples are being influenced by different conditions because the behavior of these specific enzymes in raw honeys could be a marker for the quality parameters. On the basis of this expectation, three raw honey samples tagged as blossom, pine, and oak were investigated. To reach the desired aim, extraction conditions were diversified by the range of different periods as 0, 1, 3, and 6 h and of different temperatures as 24, 45, and 65°C. The optimal heating condition and the period of extraction for invertase activity of all honey types were 24°C and 1 h because data of this condition were 147.960–178.266 enzyme unit per kilogram (U/kg) and 20.179–24.313 invertase number (IN). Although the variety of glucose oxidase activity was not evaluated as a worthwhile indicator of quality for raw honey due to its abnormal activity behavior, the change of invertase activity should be considered as a quality parameter due to showing the gradual decreasing level from initially a quite high one.


1965 ◽  
Vol 43 (2) ◽  
pp. 313-318 ◽  
Author(s):  
Rudolph V. LaMotta ◽  
Robert B. McComb ◽  
Howard J. Wetstone

The isozymes of serum cholinesterase are shown to be interconvertible. Concentration of the individual isozymes results in an electrophoretically slower functional enzyme unit, whereas dilute solutions result in functional units with greater mobility. Since each of the four most mobile isozymes when isolated is convertible to the major isozyme form and each slower isozyme when isolated can be converted into the more mobile forms, this sequence is most likely stepwise in nature. The results indicate that the isozymes of serum cholinesterase are a manifestation of a polymerization sequence.


2021 ◽  
Vol 212 ◽  
pp. 124-129
Author(s):  
E.V. Spirina ◽  
◽  
E.M. Romanova ◽  
Yu.V. Petrova ◽  
◽  
...  

The work is devoted to the study of trecresan adaptogen effect on hematological parameters of sharptooth catfish bred in an artificial environment. In particular, the effect of trecresan on general hematological parameters and antioxidant system of African sharptooth catfish was assessed, since breeding in an artificial environment is accompanied by stress, in which oxidative processes increase, leading to damage of biological membranes and disruption of cell functioning. Blood samples were analyzed using an Axio Imager.M2 microscope (Carl Zeiss, Germany). The analysis of enzymatic activity (units / mg of protein) was carried out on a UV-1800 double-beam spectrophotometer (Shimadzu, Japan). The obtained results indicate that in case of trecresan adaptogen application, there was a tendency to a proportion increase of monocytes, platelets and stab neutrophils. There is an increase of the total amount of intracel- lular hemoglobin, superoxide dismutase and catalase activity in erythrocytes and in the blood of fish bred with application of trecresan adaptogen. Trecresan induces production of interferons, increases the body immune status, activating cellular and humoral immunity, leads to a decrease of toxic products formed during lipid peroxidation by increasing the activity of enzyme unit in the antioxidant system and ensures antioxidant defense improvement of sharptooth catfish bred in an artificial environment. It strengthens the body immune system and increases resistance to adverse environmental factors. In our studies, trecresan revealed itself as a mild, effective immunomodulator.


2009 ◽  
Vol 390 (2) ◽  
pp. 167-174 ◽  
Author(s):  
Klaus Schilling ◽  
Alexandra Körner ◽  
Saskia Sehmisch ◽  
Annett Kreusch ◽  
Ramona Kleint ◽  
...  

Abstract Cathepsin L-like endopeptidases of the papain family are synthesized as proenzymes. N-terminal proregions are essential for folding and latency of the enzyme unit. While selectivity has been reported for the inhibitory function of papain-family propeptides, there is no systematic investigation of the selectivity of their chaperone-like function to date. The chaperone-like cross-reactivity between the cathepsins S, K, and L were thoroughly quantified in trans-experiments, i.e., with isolated propeptides and mature enzymes, and compared to the inhibitory cross-reactivity. The three endopeptidases have been chosen due to only minimal evolutionary distance and nearly identical X-ray structures of their zymogenes. The intramolecular chaperone function of the proregion was found to be more selective than the inhibitory activity and significant differences were found between the selectivity profiles, underlining the assumption that the inhibitory and the chaperone-like propeptide functions are autonomous. Considering the data published on the intramolecular chaperone-like propeptide function within other protease classes as well, our data suggest that intrinsically structured propeptides are more selective than intrinsically unstructured propeptides, i.e., those adopting tertiary structure elements only in complex with their maternal enzyme.


2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
R. S. S. Yadav ◽  
K. S. Yadav ◽  
H. S. Yadav

Peroxidases have turned out to be potential biocatalyst for a variety of organic reactions. The research work reported in this communication was done with the objective of finding a convenient rich source of peroxidase which could be used as a biocatalyst for organic synthetic reactions. The studies made have shown that Luffa aegyptiaca (gourd) fruit juice contains peroxidase activity of the order of 180 enzyme unit/mL. The Km values of this peroxidase for the substrates guaiacol and hydrogen peroxide were 2.0 and 0.2 mM, respectively. The pH and temperature optima were 6.5 and 60°C, respectively. Like other peroxidases, it followed double displacement type mechanism. Sodium azide inhibited the enzyme competitively with Ki value of 3.35 mM.


Sign in / Sign up

Export Citation Format

Share Document