2-Keto-D-gluconate-yielding membrane-bound D-glucose dehydrogenase from Arthrobacter globiformis C224: purification and characterization.

Glucose dehydrogenase (GlcDH) is the rate-limiting catalyst for microbial conversion of glucose to the important organic acid 2-ketogluconic acid (2KGlcA). In this study, a D-glucose dehydrogenase was purified from the industrial 2KGlcA producer Arthrobacter globiformis C224. After four purification steps, the GlcDH was successfully purified over 180 folds and specific activity of 88.1 U/mg. A single protein band of 87 kDa was detected by SDS-PAGE. The purified GlcDH had the broad substrate specificity with the Km values for D-glucose, D-xylose, D-galactose and maltose of 0.21 mM, 0.34 mM, 0.46 mM and 0.59 mM, respectively. The kinetic studies proved that A. globiformis GlcDH followed the ping-pong kinetic mechanism. The GlcDH showed an optimum catalytic activity at pH 5.0 and 45 °C with the stable activity at temperature of 20-40 °C and pH of 6.0-7.0. Organic solvents, metal ions or EDTA could significantly influence the GlcDH activity to different degrees.

Time to Occurrence of Phlebitis After Continuous Infusion of Total Nutrient Admixture Through Peripheral Veins: An Experimental Animal Study.

OBJECTIVE: To study the limit time of phlebitis caused by continuous infusion of KabivenTM Pl and TNA (KabivenTM Pl+ alanyl glutamine + potassium aspartate) through a peripheral vein, and to provide a reference for clinical formulation of preventive measures for phlebitis. METHODS: White rabbits (n = 72) were randomly divided into three groups: group A (Normal saline), group B (Kabiven™ Pl), and group C (TNA). Blood was collected from the ear margin vein before administration and after three hours, four hours, five hours, and six hours of administration. CRP and TNF-ɑ were measured by enzyme-linked immunosorbent assay. Hematoxylin and eosin staining and immunohistochemical staining were performed on tissue samples taken from the insertion point of the indwelling needle, the tip of the indwelling needle, and 1 cm from the tip of the indwelling needle, closer to the heart, to analyze early pathological changes in blood vessels. RESULTS: (1) There were no visible inflammatory symptoms in groups A, B, or C within 6 hours. (2) Four hours after starting intravenous administration, the levels of inflammatory markers in groups B and C were higher than in group A, and (3) the degree of inflammatory cell infiltration in groups B and C was more severe than in group A. (4) In all groups, the inflammatory reaction at the tip of the indwelling needle was more severe than at the other two sites. CONCLUSION: When the emulsions TNA and Kabiven™ Pl are infused through a peripheral vein, (1) four hours may be considered as the maximum time for continuous intravenous infusion in the same vein before inflammatory changes become evident, and (2) systematic assessment of the tip of the indwelling needle should be considered for inclusion in the nursing plan for phlebitis monitorings.

Correction to: The application of "upper-body yoga" in elderly patients with acute hip fracture: a prospective, randomized, and single-blind study.

In the original publication of this article [1], there are several errors that need to be corrected as below.

The application of "upper-body yoga" in elderly patients with acute hip fracture: a prospective, randomized, and single-blind study.

PURPOSES: Hip fracture leads to decreased activity and an increased risk of pulmonary complications. The main purpose of this study was to observe the lung capacity, cough capacity of the elderly patient with acute hip fracture, and assess the effects and the feasibility of using a special-designed "upper-body yoga" training to treat elderly patients with hip fracture. METHODS: This was a prospective, randomized, and single-blind study. Eighty-four subjects aged over 65 years were randomly divided into either a control group or a yoga group to undergo an abdominal breathing program or an "upper-body yoga" program until 4 weeks after surgery. The primary outcomes were forced vital capacity/predicted value (FVC%), peak cough flow (PCF), Barthel Index (BI), and the incidence of pneumonia. The secondary outcomes were the rates of right skills and inclination. RESULTS: Thirty-nine subjects in the yoga group and 40 subjects in the control group completed this study. At the end of the first training week, FVC% (74.14% ± 13.11% vs. 70.87% ± 10.46%, P = 0.231) showed no significant difference between the two groups, while the value of PCF (204.80 ± 33.45 L/min vs. 189.06 ± 34.80 L/min, P = 0.048) and BI (38.59 ± 8.66 vs. 33.00 ± 9.32, P = 0.009) in the yoga group was higher. After 4 weeks of treatment, FVC%, PCF, and BI were higher in the yoga group (78.83% ± 13.31 % vs. 72.20% ± 10.53%, P = 0.016; 216.16 ± 39.29 L/min vs. 194.95 ± 31.14 L/min, P = 0.008; 70.77 ± 10.23 vs. 65.75 ± 11.30, P = 0.019). One in the control group and nobody in the yoga group was diagnosed with pneumonia. There was no significant difference between the two groups in terms of the rates of right skills, whereas more elderly people preferred the training program of the "upper-body yoga." CONCLUSION: Elderly patients with acute hip fractures are at risk of impaired lung capacity and inadequate cough. "Upper-body yoga" training may improve the quality of daily life, vital capacity, and cough flow in elderly patients, making it a better choice for bedridden patients with hip fracture.

Improvement of D-Ribose Production from Corn Starch Hydrolysate by a Transketolase-Deficient Strain Bacillus subtilis UJS0717.

D-Ribose is a five-carbon sugar and generally used as an energy source to improve athletic performance and the ability. The culture conditions for maximum D-ribose production performance from cheap raw material corn starch hydrolysate were improved by using one-factor-at-a-time experiments and a three-level Box-Behnken factorial design. The optimal fermentation parameters were obtained as 36°C culture temperature, 10% inoculum volume, and 7.0 initial pH. The mathematical model was then developed to show the effect of each medium composition and their interactions on the production of D-ribose and estimated that the optimized D-ribose production performance with the concentration of 62.13 g/L, yield of 0.40 g/g, and volumetric productivity of 0.86 g/L·h could be obtained when the medium compositions were set as 157 g/L glucose, 21 g/L corn steep liquor, 3.2 g/L (NH4)2SO4, 1 g/L yeast extract, 0.05 g/L MnSO4·H2O, and 20 g/L CaCO3. These findings indicated the D-ribose production performance was significantly improved compared to that under original conditions.

Ultrasound-assisted lipase-catalyzed synthesis of D-isoascorbyl palmitate: process optimization and Kinetic evaluation.

BACKGROUND: D-isoascorbic acid is a food antioxidant additive and used in accordance with Good Manufacturing Practice (GMP). High solubility in water (about 150 g/L at 25°C) reduces its effectiveness in stabilizing fats and oils. Our research group had successfully synthesized D-isoascorbyl palmitate using immobilized lipase Novozym 435 as a biocatalyst. Low production efficiency of D-isoascorbyl palmitate is still a problem for industrial production due to the long reaction time of over 24 h. In the present work, ultrasonic treatment was applied for accelerating the reaction process. The operation parameters were optimized to obtain the maximum D-isoascorbyl palmitate conversion rate by using a 5-level-4-factor Central Composite Design (CCD) and Response Surface Methdology (RSM). The reaction apparent kinetic parameters under the ultrasound treatment and mechanical shaking conditions were also determined and compared. RESULTS: Results showed that ultrasound treatment decreased the reaction time by over 50%. D-isoascorbyl palmitate yielded to 94.32 ± 0.17% and the productivity reached to 8.67 g L-1 h-1 under the optimized conditions as: 9% of enzyme load (w/w), 61°C of reaction temperature, 1:5 of D- isoascorbic-to-palmitic acid molar ratio, and 137 W of the ultrasound power. The immobilized lipase Novozym 435 could be reused for 7 times with 65% of the remained D-isoascorbyl palmitate conversion rate. The reaction kinetics showed that the maximum apparent reaction rate (vmax) of the ultrasound-assisted reaction was 2.85 times higher than that of the mechanical shaking, which proved that ultrasound treatment significantly enhanced the reaction efficiency. CONCLUSION: A systematic study on ultrasound-assisted enzymatic esterification for D-isoascorbyl palmitate production is reported. The results show a promising perspective of the ultrasound technique to reduce the reaction time and improve the production efficiency. The commercial D-isoascorbyl palmitate synthesis will be potentially realized due to this ultrasound-promoted esters synthesis method.