Untitled

Abstract

An improved method for assaying of the total endodepolymerase activity of pectinases has been developed. The method is based on the determination of the viscosity of a citrus pectin solution in the presence of the enzyme using an Ostwald viscometer. The depolymerizing activity of different pectinases can be detected including polygalacturonase, polymethylgalacturonase, pectin lyase, and pectate lyase. One unit of the endodepolymerase activity corresponds to the activity resulting in 50% decrease in the relative viscosity of 0.5% citrus pectin solution for 5 min at 40 degrees C and the appropriate pH. Depending on the pH-optima of the enzymes, two modifications of the method are described: 1) for acid pectinases at pH 5.0, and 2) for neutral (mildly alkaline) pectinases at pH 8.0. The modifications differed in the control and in the calculation of the activity. Six enzyme preparations were used to demonstrate the applicability of the method. The parameter used for the calculation of the enzymatic activity was directly proportional to the enzyme concentration (the dependence was linear in the range of at least 10-fold change in the enzyme concentration). The relative error of the method did not exceed 10%.

Systems Approach in Construction—scientific School of A. A. Gusakov (Social-Communicative Survey)

“…In this respect, the experience of Prof A. A. Gusakov supervising joint projects associated with publishing monographs together with the Slovak [23][24][25][26][27][28][29][30][31][32][33][34][35][36], French [ 19] and American [22] scientists or making the translations of most relevant foreign publications is rather instructive. The authors of the present paper followed suit having published two monographs [73,74] in cooperation with German authors and one together with Polish researchers [72].…”

Effect of Combined Heat‐Moisture/Lactic Acid Treatment on the Physicochemical and In Vitro Digestibility Properties of Corn Starch

“…The total reducing sugars contained in the native and modified starch samples before washing were estimated by the 3,4‐dinitrosalicylic acid method [ 16,17 ] using a solution of 10 m m glucose as standard.…”

Advances in Denim Research

“…In the case of most enzymes, under neutral conditions the optimal temperature lies between 30-70 °C [30][31][32][33]. It is necessary to avoid back staining during enzymatic treatment as there is possibility of re-deposition of the indigo dye that is removed, on the white weft yarn of the denim fabric [34]. The most conventional and primary technique of enzyme application in textile finishing relates to processing with α-amylases [35].…”

“…The main advantages of enzymes used in denim finishing are efficiency, accelerated reactions, being operational under mild conditions, acting on a specific substrate exclusively, easiness of control, biodegradability, and a wide range of industrial applications. Optimal temperature range for most enzymes is 30-70 °C under neutral conditions [8][9][10][11][12]. Stretch fabrics are increasingly being used across the whole gamut of clothing applications, such as fashion, sportswear, medical and functional garments [1].…”