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Objective: In order to control the potassium ion content in Carrageenan, this project used alcohol inhibition method instead of potassium ion solution to extract Carrageenan. Methods: The volume fraction of ethanol in the processes of alkali treatment, alkali residual cleaning, and precipitation of carrageenan after filtration during the extraction were optimized for controlling K+ concentration. Results: The concentration of ethanol to inhibit the dissolution of Carrageenan was 60% in the process of alkali treatment and cleaning residual alkali, and the ratio of 60% ethanol solution to glue solution was 5∶1 in the process of Carrageenan precipitation. By using this process, the yield of Carrageenan was （28.76±1.38）%, and the Carrageenan of potassium ion was 0.63%, which was significantly lower than that of potassium ion extracted from traditional Carrageenan （16.26%）. In addition, the gel strength was significantly lower than that of Carrageenan extracted by traditional methods. And there was no significant difference in viscosity, hardness, elasticity, chewiness, and recovery between the two methods. Conclusion: K+ concentration and gel strength of Kappa-carrageenan extracted by ethanol inhibition were significantly lower than traditional technology.

To examine postnatal changes in the impaired brainstem auditory pathway in term infants after perinatal hypoxia-ischemia (HI). Brainstem auditory evoked response (BAER) was studied at 2–4 months of age in term infants who suffered perinatal HI. The BAER data obtained at various click rates in these infants were compared with those in age-matched normal term controls to detect any abnormalities. The infants after HI showed a slight elevation in BAER threshold. Four (9.8%) infants had threshold elevation. At 21/s clicks, there was a slight decrease in wave I latency, and a slight increase in wave III and V latencies. However, the I–V and I–III intervals in these infants were significantly increased (p <.05 and.05), whereas III–V interval was slightly increased. At higher click rates of 51 and 91/s, all BAER variables showed similar changes, with only small variations. An abnormal increase in the I–V and/or I–III intervals was seen in 4 (9.8%) infants, who were not associated with BAER threshold elevation. At 2–4 months of age, around 20% of the infants after perinatal HI showed a moderate degree of either peripheral or central impairment of the brainstem auditor pathway. Monitoring postnatal changes could provide valuable information for postnatal care of infants after perinatal HI. [ABSTRACT FROM AUTHOR]

The agarase gene AL1 was amplified by PCR and cloned into pET-28a expression vector. The expression product was purified by affinity chromatography to study the enzymatic properties of the recombinant enzyme. The enzymatic hydrolysate was identified by TLC and LC-MS, and its reducing ability and scavenging ability of DPPH, ABTS+- and OH radicals were determined, and the antioxidant activity of the hydrolysate was analyzed. The molecular weight of the recombinant agarase from Agarivorans sp. AL1 was 105 ku. The agarase could specifically degrade agar as a β-agarase. The recombinant agarase showed the maximum activity at 50 °C and pH 7.00. The recombinant agarase was stable in a wide pH range from 5.00 to 11.00 below 50 C, indicating that the recombinant enzyme had good thermal stability and pH stability. The enzymatic hydrolysate product was identified as neoagarobiose by TLC and LC-MS. The enzymatic hydrolysates had the reducing power. The half-inhibition concentration IC50 of the enzymatic hydrolysate to OH, ABTS and DPPH free radicals are 1.28 mg/mL, 3.46 mg/mL and 9.87 mg/mL, respectively, indicating that the hydrolysate had good antioxidant activity. [ABSTRACT FROM AUTHOR]

Isoquercitrin is a flavonoid with important applications in the pharmaceutical and nutraceutical industries. However, a low yield and high production cost hinders the industrial preparation of isoquercitrin. In the present study, isoquercitrin was prepared by biotransformation of rutin using α-L-rhamnosidase from Aspergillus niger JMU-TS528 combined with high-speed countercurrent chromatography (HSCCC) purification. As a result, the optimum transformation pH, temperature, and time were pH 4.0, 60 °C, and 60 min, respectively. The Km and Vmax were 0.36 mM and 0.460 mmol/min, respectively. For isoquercitrin production, the optimal rutin concentration and transformation time were approximately 1000 mg/L and 60 min. The rutin transformation rate reached 96.44%. The isoquercitrin was purified to a purity of 97.83% using one-step purification with HSCCC. The isoquercitrin was identified using UPLC-Q-TOF-MS. The comprehensive results indicated that the biotransformation procedure using the α-L-rhamnosidase from A. niger JMU-TS528 combined with HSCCC was a simple and effective process to prepare isoquercitrin, which might facilitate the production of isoquercitrin for industrial use. [ABSTRACT FROM AUTHOR]

Objectives: To examine short-term outcome of brainstem auditory function in term infants after discharge from the neonatal intensive care unit (NICU).Methods: Brainstem auditory evoked response (BAER) was recorded and analysed at various click rates at 2-4 months of age in 43 term NICU graduates. The data were compared with those in age-matched normal controls.Results: The threshold of BAER in the NICU graduates was marginally elevated. The graduates also showed an increase in wave III latency at 91/s and wave V latency at all 21-91/s. The I-V interval was increased at 51 and 91/s, whereas the I-III and III-V intervals were slightly increased, with no significant differences from normal controls at any click rates. The amplitudes of waves I and V in the NICU graduates were moderately reduced at all click rates. Wave III amplitudes were reduced at 51 and 91/s. None of the slopes of BAER variables-rate functions in the NICU graduates differed significantly from normal controls.Conclusions: The BAER was moderately abnormal in the NICU graduates, suggesting that brainstem auditory function is moderately impaired at 2-4 months of age after discharge. There is a need to monitor postnatal auditory and neural development for NICU graduates. [ABSTRACT FROM AUTHOR]

Objective To examine brainstem auditory electrophysiology in high-risk babies born at 28–32 week gestation by analysing the amplitudes of wave components in maximum length sequence brainstem auditory evoked response (MLS BAER). Methods 94 preterm babies, ranging in gestation 28–32 weeks, with perinatal problems (high-risk) were recruited. The amplitudes of MLS BAER wave components were studied at term age (37–42 weeks postconceptional age). Results Compared with normal term controls, the amplitude in the high-risk preterm babies was significantly smaller at the highest click rate 910/s for wave I ( p < 0.01), at all 91–910/s for wave III (all p < 0.01) and at 455 and 910/s ( p < 0.05 and 0.01) for wave V. Compared with age-matched low-risk preterm controls, the amplitude was significantly smaller at 455 and 910/s for wave I ( p < 0.05 and 0.05), 91–910/s for wave III ( p < 0.05–0.001), and 227–910/s ( p < 0.05 and 0.01) for wave V. No differences in the V/I and V/III amplitude ratios were found between the high-risk preterm babies and the controls. Conclusions The amplitudes of MLS BAER wave components, mainly more central components, were reduced in the high-risk preterm babies born at 28–32 week gestation. Electrophysiological activity of the brainstem auditory neuron in such babies is depressed, mainly attributed to or related to the associated perinatal problems. [ABSTRACT FROM AUTHOR]