Effects of dietary glycerol monolaurate on productive performance, egg quality, serum biochemical indices, and intestinal morphology of laying hens / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Glycerol monolaurate (GML) has been widely used as an effective antibacterial emulsifier in the food industry. A total of 360 44-week-old Hy-Line brown laying hens were randomly distributed into four groups each with six replicates of 15 birds, and fed with corn-soybean-meal-based diets supplemented with 0, 0.15, 0.30, and 0.45 g/kg GML, respectively. Our results showed that 0.15, 0.30, and 0.45 g/kg GML treatments significantly decreased feed conversion ratios (FCRs) by 2.65%, 7.08%, and 3.54%, respectively, and significantly increased the laying rates and average egg weights. For egg quality, GML drastically increased albumen height and Haugh units, and enhanced yolk color. Notably, GML increased the concentrations of polyunsaturated and monounsaturated fatty acids and reduced the concentration of total saturated fatty acids in the yolk. The albumen composition was also significantly modified, with an increase of 1.02% in total protein content, and increased contents of His (4.55%) and Glu (2.02%) under the 0.30 g/kg GML treatment. Additionally, GML treatments had positive effects on the lipid metabolism of laying hens, including lowering the serum triglyceride and total cholesterol levels and reducing fat deposition in abdominal adipose tissue. Intestinal morphology was also improved by GML treatment, with increased villus length and villus height to crypt depth ratio. Our data demonstrated that GML supplementation of laying hens could have beneficial effects on both their productivity and physiological properties, which indicates the potential application of GML as a functional feed additive and gives us a new insight into this traditional food additive.

Screening, purification, and characterization of an extracellular lipase from Aureobasidium pullulans isolated from stuffed buns steamers / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

An extracellular lipase from Aureobasidium pullulans was obtained and purified with a specific activity of 17.7 U/mg of protein using ultrafiltration and a DEAE-Sepharose Fast Flow column. Characterization of the lipase indicated that it is a novel finding from the species A. pullulans. The molecular weight of the lipase was 39.5 kDa, determined by sodium dodecyl sulfonate-polyacrylamide gel electrophoresis (SDS-PAGE). The enzyme exhibited its optimum activity at 40 °C and pH of 7. It also showed a remarkable stability in some organic solutions (30%, v/v) including n-propanol, isopropanol, dimethyl sulfoxide (DMSO), and hexane. The catalytic activity of the lipase was enhanced by Ca2+ and was slightly inhibited by Mn2+ and Zn2+ at a concentration of 10 mmol/L. The lipase was activated by the anionic surfactant SDS and the non-ionic surfactants Tween 20, Tween 80, and Triton X-100, but it was drastically inhibited by the cationic surfactant cetyl trimethyl ammonium bromide (CTAB). Furthermore, the lipase was able to hydrolyze a wide variety of edible oils, such as peanut oil, corn oil, sunflower seed oil, sesame oil, and olive oil. Our study indicated that the lipase we obtained is a potential biocatalyst for industrial use.

Analysis of ant oil extracted with supercritical CO2 fluid from Polyrhachis vicina by GC-MS / 中国中药杂志

<p><b>OBJECTIVE</b>To study the optimum extraction parameters and components on ant oil from Polyrhachis vicina.</p><p><b>METHOD</b>The optimum condifious for supercritical CO2 fluid extraction (SFE-CO2), were investigated with orthogonal design, GC-MS was applied for analyzing. The components and their contents in the ant oil were analyzed by GC-MS, and the contents of lead, zinc and manganese in the oil were determined by ICP-AES.</p><p><b>RESULT</b>The optimum extraction parameters were achieved, temperature of 50 degrees C, pressure of 30 MPa and time of 2 hours. The extracting yield of the ant volatile oil was 11.4% - 14.3%. 51 Constituents were identified including 9-octadecenoic acid, ethyl oleate, cholesterol, n- Hexadecanoic acid, etc, and the content of various constituents was determined by orea normalization. The oil contained unsaturated fatty acid of 64.6%, lead of 0.80 microg x g(-1), zinc of 0.54 microg x g(-1) and manganese of 0.15 microg x g(-1).</p><p><b>CONCLUSION</b>The method showes advantages including faster and efficient of extraction, good quality and no solvent residues in the oil.</p>