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The food enzyme AMP deaminase (AMP aminohydrolase; EC 3.5.4.6) is produced with the non‐genetically modified Streptomyces murinus strain AE‐DNTS by Amano Enzyme Inc. The food enzyme is free from viable cells. It is intended to be used in yeast processing and the production of mushroom extracts. Dietary exposure to the food enzyme–total organic solids (TOS) was estimated to be up to 0.0004 mg TOS/kg body weight (bw) per day in European populations. The food enzyme batches, including the batch used in the toxicological studies, were not fully characterised. A search for the similarity of the amino acid sequence of the food enzyme to known allergens was made and no match was found. The Panel considered that, under the intended conditions of use, the risk of allergic reactions by dietary exposure cannot be excluded, but the likelihood is low. In the absence of adequate toxicological data, the Panel could not conclude on the safety of the food enzyme AMP deaminase from the non‐genetically modified Streptomyces murinus strain AE‐DNTS. [ABSTRACT FROM AUTHOR]

The food enzyme is a glucose isomerase (d‐xylose aldose‐ketose‐isomerase; EC 5.3.1.5) produced with a non‐genetically modified Streptomyces murinus strain NZYM‐GA by Novozymes A/S. The glucose isomerase is intended only to be used in an immobilised form in glucose isomerisation for the production of high fructose syrups. Residual amounts of total organic solids are removed by the purification steps applied during the production of high fructose syrups using the immobilised enzyme; consequently, dietary exposure was not calculated. Genotoxicity tests did not raise a safety concern. Similarity of the amino acid sequence to those of known allergens was searched and no match was found. The Panel considered that, under the intended conditions of use, the risk of allergic sensitisation and elicitation reactions by dietary exposure cannot be excluded, but the likelihood to occur is considered to be low. Based on the data provided, the immobilisation process and the removal of total organic solids during the production of high fructose syrups, the Panel concluded that this food enzyme does not give rise to safety concerns under the intended conditions of use. [ABSTRACT FROM AUTHOR]

• Amyloglucosidase and glucose isomerase have been used to produce fructose syrup. • Their immobilization permit the combined use of the enzymes. • The addition of Mg2+ prevent negative effects of Ca2+. • As one biocatalyst is magnetic, it can be separated from the other biocatalyst. • They could be reused for six consecutive cycles without significant activity decrease. High fructose syrup is a sweetener widely used as a substitute for sucrose in the food and beverage industry with its current industrial production being carried out in three sequential processes using three different enzymes that operate under different pH and temperature conditions. In this study, a single step synergistic saccharification and isomerization process has been proposed, using the commercial amyloglucosidase from Aspergillus niger immobilized by the CLEA technique (co-aggregated with magnetic nanoparticles and polyethyleneimine), and the commercial immobilized glucose isomerase (IGI) from Streptomyces murinus , Sweetzyme® IT Extra. Immobilization stabilized both enzymes, widening the operation window, thus, by applying a factorial design with a central composite rotatable design it was possible to define an optimal condition of pH and temperature of the process, as well as the best ratio between the two enzymes (pH 5.7, 50 °C and U GI /U AMG ratio of 1.56). Simultaneous saccharification and isomerization of 35 % (w/v) dextrin solution produced a Dextrose Equivalent yield over 95 %, with a glucose-to-fructose conversion around 48 % after 30 h of reaction. In addition, both biocatalysts could be reused for six consecutive cycles, maintaining glucose-to-fructose conversions without loss of activity and with easy recovery of the biocatalysts. Furthermore, because they are of different natures (magnetic CLEA of amyloglucosidase and non-magnetic IGI pellets), if one of these biocatalysts is inactivated, they can be easily separated and reloaded individually. [ABSTRACT FROM AUTHOR]

Organosulfur compound's functionality constitutes an essential class of therapeutic agents in current medicinal chemistry. Especially sulfonamides called sulfa drugs were performed as both chemotherapeutic agents and useful antibacterial derivatives developed for medicine. The sulfamides in the same family with the sulfonamides have similar biological activities. In our research, it was studied with some 3-imino-4-substituted-1, 2, 5-thiadiazolidine 1,1-dioxides (ISTDs- 4a-d, four samples) that are five-membered cyclosulfamides. These compounds were previously synthesized and structurally characterized. The goals of this study are to investigate minimum inhibition concentration (MIC) values and antibacterial effects of these ISTDs compounds on Bacillus subtilis NRRL B-209T, Escherichia coli ATCC®25922T, Micrococcus luteus NRRL B-1018T, Nocardia abscessus DSM 44432T, Nocardia cyriacigeorgica DSMZ 44484T, Pseudomonas aeruginosa NRRL B-2679T Staphylococcus aureus ATCC®6538T, Streptomyces murinus ISP 5091T. [ABSTRACT FROM AUTHOR]

Abstract: Trehalose phosphorylase from the basidiomycete Pleurotus ostreatus (PoTPase) was isolated from fungal fruit bodies through ∼500-fold purification with a yield of 44%. Combined analyses by SDS-PAGE and gelfiltration show that PoTPase is a functional monomer of ∼55kDa molecular mass. PoTPase catalyzes the phosphorolysis of α,α-trehalose, yielding α-d-glucose 1-phosphate (αGlc 1-P) and α-d-glucose as the products. The optimum pH of PoTPase for α,α-trehalose phosphorolysis and synthesis is 6.8 and 6.2, respectively. Apparent substrate binding affinities (K m) were determined at pH 6.8 and 30°C: α,α-trehalose (79mM); phosphate (3.5mM); d-glucose (40mM); αGlc 1-P (4.1mM). A series of structural analogues of d-glucose were tested as glucosyl acceptors for the enzymatic reaction with αGlc 1-P, and robust activity with d-mannose (3%), 2-deoxy d-glucose (8%), 2-fluoro d-glucose (15%) and 2-keto-d-glucose (50%) was detected. Arsenate replaces, with 30% relative activity, phosphate in the conversion of α,α-trehalose, and vanadate strongly inhibits the enzyme activity (K i ∼4μM). PoTPase has a half-life (t 0.5) of approximately 1h at 30°C in the absence of stabilizing compounds such as α,α-trehalose (300mM; t 0.5 =11.5h), glycerol (20%, w/v; t 0.5 =6.5h) or polyethylenglycol (PEG) 4000 (26%, w/v; t 0.5 =70h). Covalent modification of PoTPase with activated derivatives of PEG 5000 increases the stability by up to 600-fold. Sucrose was converted to α,α-trehalose in ∼60% yield using a coupled enzyme system composed of sucrose phosphorylase from Leuconostoc mesenteroides, glucose isomerase from Streptomyces murinus and the appropriately stabilized PoTPase. [Copyright &y& Elsevier]

Cellobiose is a zero-calorie functional sweetener and a potential healthy food/feed additive. Current production methods of cellobiose from high-purity cellulose always suffer from low product yields and high separation costs. Here one-pot biotransformation composed of three thermophilic enzymes sucrose phosphorylase (SP) from Thermoanaerobacterium thermosaccharolyticum , glucose isomerase (GI) from Streptomyces murinus , and cellobiose phosphorylase (CBP) from Clostridium thermocellum was designed to convert sucrose to cellobiose. To reveal the underlying relationship within the three enzymes and optimize reaction conditions, a kinetic model was developed. Model simulation predicted the optimal SP:GI:CBP enzyme loading ratio in terms of enzyme unit was 0.5:1.0:1.5. The enzyme cocktail with the optimal ratio converted 100 mM sucrose to 62.3 mM cellobiose within 10 h. Model simulation also found out that the optimal phosphate concentration was approximately 10.3 mM for 100 mM sucrose, which was validated by experimental data. This study could assist the sugar industry to diversify the production of new value-added products from sucrose. [ABSTRACT FROM AUTHOR]

Abstract: The synthetic effect of the combination use of ultrasound irradiation (UI) and ionic liquid (IL) on improving enzyme activity was studied when they were employed in isomerization of glucose to fructose by immobilized glucose isomerase (IGI, produced from streptomyces murinus and immobilized on silica). Both of UI and IL [EMIM][Cl], which was screened as the best medium for this reaction, were found to increase the enzyme activity in isomerization reaction. And a further increase of enzyme activity was observed by combination use of UI and IL. A systematic screening and optimization of the reaction parameters in ILs under UI on the IGI activity were performed. Under the optimum reaction conditions, 45.3% yield of fructose was achieved in 10h under UI in [EMIM][Cl], compared to only 41.5% yield under stirring in [EMIM][Cl], 44.2% under UI without [EMIM][Cl] and 38.9% under stirring without [EMIM][Cl] in 12h, respectively. High thermal stability and reusability of IGI was also observed under UI in [EMIM][Cl]. These results indicated that the combination use of UI and IL might be a fast and efficient method for enzymatic isomerization of glucose to fructose. [Copyright &y& Elsevier]

Abstract: The isomerization of glucose to fructose by immobilized glucose isomerase (IGI, produced from Streptomyces murinus and immobilized on silica) was conducted under two different conditions—microwave irradiation and conventional heating to compare their overall effects. It was found that compared with conventional heating, microwave irradiation significantly enhanced the activity of IGI and the effects of acceleration might be non-thermal microwave effect. Under the optimum conditions of microwave irradiation-assisted isomerization (magnesium ion concentration of 50mM, 0.1M pH 7.5 phosphate buffered saline (PBS) buffer, 70°C, microwave power of 480W, agitation speed of 150rpm, glucose concentration of 0.8M and 2% IGI based on the solution weight percentage), 45% yield of fructose could be achieved in 16h, while only 43% yield of fructose was obtained until 24h by using conventional heating. These results indicated that microwave irradiation might be a fast and efficient method for enzyme-catalyzed isomerization of glucose to fructose. [Copyright &y& Elsevier]

Plectosporium tabacinum root rot disease of white lupine is reported for the first time in Cairo Governorate provinces. Symptoms of the disease appeared on young seedlings as stunting, yellowing and wilting of the foliage. Rotted roots were first became light brown and the lesions progressively extended over the whole root system and became dark brown. Plants died when the whole root system had become infected. For successful biological control of the disease 70 rhizosphere actinomycetes were isolated by the use of normal standard isolation techniques. Three of these isolates were found to be strongly antagonistic against P. tabacinum in vitro. They also significantly reduced the incidence of white lupine root rot disease in soil infested with P. tabacinum in greenhouse trials. The three actinomycete isolates were identified as Streptomyces cyanoviridis, Streptomyces murinus and Streptomyces griseoplanus. [ABSTRACT FROM AUTHOR]