Biosynthesis of glycosidase inhibitors on wheat bread wastes hydrolysate medium by Streptomyces sp. 170

ArticleThe aim of the present study is to investigate the potential effect of bread hydrolysate as a novel nutrient medium for cultivating Streptomyces sp. 170 (S.170). Moreover, it evaluates the productivity and inhibitory activity of pancreatic α-amylase inhibitors (PAAI). Bread hydrolysate medium (BHM) and corn starch hydrolysate medium (CHM) prepared with αamylase enzyme concentrations (1.5 and 2.5 units g -1 bread) and (1.5 units g -1 corn starch), respectively were utilized in the study. The Seherde-Blair and modified Akulova methods were applied to evaluate the carbohydrates concentration and the inhibitory activity of the media respectively. Results of bread and corn media were compared to each other. Furthermore, the activity of PAAI synthesized by S.170 was compared to other Streptomyces species. The results showed a significant difference (P < 0.05) between the total simple sugars (glucose + maltose) concentration produced in CHM (27.5%) and BHM prepared with α-amylase 1.5 units (45.1%). Besides, BHM produced by α-amylase 2.5 units demonstrated the maximum total concentration of simple sugars (49.9%). In addition, 48 h of S.170 incubation were quite enough to exhibit the highest inhibitory activity (2,632 IU mL-1 ) in BHM prepared with α-amylase 2.5 units. The analysis demonstrated a non-significant difference in the inhibitory activity of PAAI in CMH (1,300 IU mL-1 ) and BMH with α-amylase 1.5 units (1,111 IU mL-1 ). Also, compared to other Streptomyces species, S.170 conferred highly active PAAI. In conclusion, BHM showed its efficiency to a great extent in the cultivation of S.170 and production of PAAI with a notable high activity

Features of low-temperature storage of streptomyces strains - producers of glycosidaz inhibitors

The aim of the work is to study the inhibitory activity of the Streptomyces lucensis VKPM Ac-1743 and Streptomyces violaceus VKPM Ac-1734 strains stored at –18 °C in a 15 % glycerol solution and in a 0.9 % sodium chloride solution.The object of the study was the actinomycete strains of S. lucensis VKPM Ac-1743 and S. violaceus VKPM Ac-1734 producers of glycosidase inhibitor, which is a micro-ingredient for creating products with a low glycemic index. The storage time was nine months. Bookmark storage was performed by flushing with a taped agar starchcontaining environment of Capek. For comparison, we studied the properties of cultures stored at +4 °C without cryoprotectant.Deep cultivation of Streptomyces strains was carried out in a periodic manner on a medium containing corn starch hydrolyzate under the Multitron incubator shaker (INFORS,Switzerland).Inhibitory activity was determined in inactivated native solutions by a colorimetric method with respect to pancreatic α-amylase, a test glycosidase involved in carbohydrate metabolism, and whose activity was chosen as a criterion for assessing the hypoglycemic action of the inhibitor. The proteinase activity of the inactivated native solution was determined by a modified method using a casein substrate.The experimental data were processed using the methods of mathematical statistics and Excel XP programs.As a result of the research, it was established that the actinomycete strains of S. lucensis and S. violaceus, the producers of glycosidase inhibitors, can maintain inhibitory activity during low-temperature storage for nine months.For the S. lucensis actinomycete strain, stored in a 15 % glycerol solution at – 18 °C, the maximum inhibitory activity is 48 hours in the biotechnological process and is (3686 ± 300) IU/cm3 native solution, and for the violaceus strain – (3150 ± 200) IU/cm³ of the native solution, respectively.For the strain of actinomycete S. lucensis, stored in 0.9 % sodium chloride solution at a temperature of – 18 °C, the maximum inhibitory activity accounts for 72 h of the biotechnological process and is (2600 ± 200) IU/cm³ of the native solution, and for the strain S. violaceus the maximum inhibitory activity accounts for 24 hours of the biotechnological process and is (3530 ± 200) IU/cm³ of the native solution.At a storage temperature of +4 °C, the inhibitory activity for the strain of actinomycete S. lucensis is (560 ± 20) IU/cm³ of native solution, and for the strain of S. violaceus – (1747 ± 100) IU/cm³ of native solution, respectively. On the basis of the data obtained, it can be concluded that a temperature of –18 °C is preferred for long-term storage.During the cultivation of Streptomyces strains, proteinase activity ranged from (0,012 ± 0,001) U/cm³ to (0,072 ± 0,002) U/cm³.The obtained data can be applied in further studies to develop conditions for long-term storage of collection crops.The aim of the work is to study the inhibitory activity of the Streptomyces lucensis VKPM Ac-1743 and Streptomyces violaceus VKPM Ac-1734 strains stored at –18 °C in a 15 % glycerol solution and in a 0.9 % sodium chloride solution.The object of the study was the actinomycete strains of S. lucensis VKPM Ac-1743 and S. violaceus VKPM Ac-1734 producers of glycosidase inhibitor, which is a micro-ingredient for creating products with a low glycemic index. The storage time was nine months. Bookmark storage was performed by flushing with a taped agar starchcontaining environment of Capek. For comparison, we studied the properties of cultures stored at +4 °C without cryoprotectant.Deep cultivation of Streptomyces strains was carried out in a periodic manner on a medium containing corn starch hydrolyzate under the Multitron incubator shaker (INFORS,Switzerland).Inhibitory activity was determined in inactivated native solutions by a colorimetric method with respect to pancreatic α-amylase, a test glycosidase involved in carbohydrate metabolism, and whose activity was chosen as a criterion for assessing the hypoglycemic action of the inhibitor. The proteinase activity of the inactivated native solution was determined by a modified method using a casein substrate.The experimental data were processed using the methods of mathematical statistics and Excel XP programs.As a result of the research, it was established that the actinomycete strains of S. lucensis and S. violaceus, the producers of glycosidase inhibitors, can maintain inhibitory activity during low-temperature storage for nine months.For the S. lucensis actinomycete strain, stored in a 15 % glycerol solution at – 18 °C, the maximum inhibitory activity is 48 hours in the biotechnological process and is (3686 ± 300) IU/cm3 native solution, and for the violaceus strain – (3150 ± 200) IU/cm³ of the native solution, respectively.For the strain of actinomycete S. lucensis, stored in 0.9 % sodium chloride solution at a temperature of – 18 °C, the maximum inhibitory activity accounts for 72 h of the biotechnological process and is (2600 ± 200) IU/cm³ of the native solution, and for the strain S. violaceus the maximum inhibitory activity accounts for 24 hours of the biotechnological process and is (3530 ± 200) IU/cm³ of the native solution.At a storage temperature of +4 °C, the inhibitory activity for the strain of actinomycete S. lucensis is (560 ± 20) IU/cm³ of native solution, and for the strain of S. violaceus – (1747 ± 100) IU/cm³ of native solution, respectively. On the basis of the data obtained, it can be concluded that a temperature of –18 °C is preferred for long-term storage.During the cultivation of Streptomyces strains, proteinase activity ranged from (0,012 ± 0,001) U/cm³ to (0,072 ± 0,002) U/cm³.The obtained data can be applied in further studies to develop conditions for long-term storage of collection crops

Beta-glucans from biomass of plant and microbial origin

The aim of the present study is to explore the transformation of (1→3)(1→4)-β-D-glucans of rye biomass by Aspergills niger and accumulation of (1→3)(1→6)-β-D-glucans in the microbial cell wall.Biomass from rye grain was obtained as a result of enzymatic hydrolysis of grain grinding of Omsk region of non-standard quality with grain impurity content of 45 ± 2 % by preparations (1→4)-β-glucanolytic, (1→3)-β-glucanolytic, (1→4)-xylanolytic and (1→4)-amylolytic action. Fermentation of hydrolysates, sucrosemineral and molasses medium by A. niger was carried out by a batch process under aerobic conditions. Determined the content of β-glucans, amino-nitrogen, glucose, disaccharides in grinding grain rye, rye biomass, the biomass of A. niger, the supernatants by colorimetric methods. Determination of chitin in biomass and qualitative determination of chitosan in supernatants of hydrolysates was carried out using chitosan sulfate sample and subsequent microscopy.The results of the research showed that (1→3)(1→4)-β-D-glucans in grain grinding are 10.2 ± 0.2 % in terms of dry matter, which exceeds the content of polysaccharide in the grain of standard quality by 1.5 – 3 times. In rye biomass revealed their smaller amount, 6.4 ± 0.5 %, apparently, due to the action of (1→4)and (1→3)-β-glucanase, (1→4)-xylanase and (1→4)-amylase. In microbial mass A. niger content of (1→3)(1→6)-β-Dglucans were at the level of 21.7 ± 0.7 %.On the basis of the obtained results, it was concluded that it is possible to use rye grain of non-standard quality, with a high content of grain impurities and a low proportion of starch polysaccharides, as a source of β-glucancontaining substrate for biosynthesis (1→3)(1→6)-β-D-glucans by A. niger having advantages over (1→3) (1→4)-β-D-glucans of plant origin. They are functionally more active and have a wide range of applications, namely as food additives in the manufacture of a wide range of products: for the enrichment of fibers, increasing the shelf life of products due to its water-binding properties, as thickeners, emulsifying and fat-reducing microingredients, stabilizers of creamy emulsions, textureformers, flavor enhancers.The aim of the present study is to explore the transformation of (1→3)(1→4)-β-D-glucans of rye biomass by Aspergills niger and accumulation of (1→3)(1→6)-β-D-glucans in the microbial cell wall.Biomass from rye grain was obtained as a result of enzymatic hydrolysis of grain grinding of Omsk region of non-standard quality with grain impurity content of 45 ± 2 % by preparations (1→4)-β-glucanolytic, (1→3)-β-glucanolytic, (1→4)-xylanolytic and (1→4)-amylolytic action. Fermentation of hydrolysates, sucrosemineral and molasses medium by A. niger was carried out by a batch process under aerobic conditions. Determined the content of β-glucans, amino-nitrogen, glucose, disaccharides in grinding grain rye, rye biomass, the biomass of A. niger, the supernatants by colorimetric methods. Determination of chitin in biomass and qualitative determination of chitosan in supernatants of hydrolysates was carried out using chitosan sulfate sample and subsequent microscopy.The results of the research showed that (1→3)(1→4)-β-D-glucans in grain grinding are 10.2 ± 0.2 % in terms of dry matter, which exceeds the content of polysaccharide in the grain of standard quality by 1.5 – 3 times. In rye biomass revealed their smaller amount, 6.4 ± 0.5 %, apparently, due to the action of (1→4)and (1→3)-β-glucanase, (1→4)-xylanase and (1→4)-amylase. In microbial mass A. niger content of (1→3)(1→6)-β-Dglucans were at the level of 21.7 ± 0.7 %.On the basis of the obtained results, it was concluded that it is possible to use rye grain of non-standard quality, with a high content of grain impurities and a low proportion of starch polysaccharides, as a source of β-glucancontaining substrate for biosynthesis (1→3)(1→6)-β-D-glucans by A. niger having advantages over (1→3) (1→4)-β-D-glucans of plant origin. They are functionally more active and have a wide range of applications, namely as food additives in the manufacture of a wide range of products: for the enrichment of fibers, increasing the shelf life of products due to its water-binding properties, as thickeners, emulsifying and fat-reducing microingredients, stabilizers of creamy emulsions, textureformers, flavor enhancers