Advanced Materials Research Vols. 361-363

Abstract: Four lactic acid bacteria (LAB) strains named HN78, HN87, HN91 and HN113 were separated from Stylosanthes guianensis SW. of Hainan province, which were identified bacterially using the classical classification and the sequences of 16S rDNA. The results showed that four strains were Enterococcus hirae, Enterococcus faecalis, Lactococcus lactis and Lactobacillus plantarum. The capability of lactic acid production of HN113 and HN91 were better than HN78 and HN87.

Abstract: Extraction of total flavonoids from red kidney bean was studied by combination method of microwave and light wave radiation without solvent. Heating the sample for 8 min with power 800W (microwave 55% and light wave 45%), the total flavonoids were extracted with ethyl alcohol.The extraction ratio of total flavonoids is 1.04%, that is close with that of corresponding conventional extraction process. This method had many merits, such as simple, rapid, low cost, etc. Extraction mechanism was investigated preliminarily with high magnification fluorescence microscope FM, IR. It indicated that improvement of extraction efficiency of secondary metabolite is possibly because that plant tissue cell structure was changed by microwave.

Abstract: Ferulic acid, a compound showing antioxidant ability, is found in abundance in wheat bran. Its release depends mainly on the breaking of its ester linkage to other constitutive elements of the cell wall, such as arabinoxylans, ligin, cellulose and so on. Response surface methodology and orthogonal design were respectively used to evaluate the effects of NaOH concentration, alkali/ethanol ratio, extraction temperature and pH on ferulic acid extraction yield from wheat bran. The released ferulic acid concentration was determinated by HPLC method Experiments carried out under the predicted optimal conditions，with NaOH concentration of 5.76%, pH of 3.2, alkali/ethanol ratio of 1.39:1, temperature of 59.75 °C, the actual extraction yield in agreement with the expected yield, with 4.45mg.g^-1 extraction rate of ferulic acid in wheat bran . And the results confirm the potential of wheat bran valorization in the field of natural antioxidant extraction, possibly viable in an industrial scheme.

Abstract: It is a problem of the ice with transient heat of the solidification and melting which usually is a part of "phase change" or "moving boundary". The paper is a research about measurement and analysis of the icing in the rectangular tank outdoor under natural conditions, the paper adopts the method which combines theoretical analysis with experimental verification to establish a mathematical model of the unstable-state and dynamic cool storage in one-dimensional rectangular coordinate system. Conclusion is drawn that the thickness of water icing in the natural conditions according to the change of the time and environmental condition, which provide a theoretical basis to determine the best program of the frozen, the frozen time and the best size of the frozen container. It is helpful for the further research of the icing store in the winter ice and make the best of natural resources in the north winter.

Abstract: Supercritical CO₂ was used to extract effective compounds from pine pollen, MTT colorimetric method was applied to determine anti-cancer effect of effective compounds in pine pollen. Results indicated that extracts obtained at pressure ranges 0~30 MPa and 10~15 MPa had significant inhibition effect on the lung cancer cells 95D of pig (95D) and their IC50 value was 253.22 μg/mL and 252.19 μg/mL, respectively. Extracts attained at pressure ranging 0~10 MPa, 10~15 MPa and 0~30 MPa had significant inhibition effect on the stomach cancer cells SGC-7901 of human (SGC-7901), and their IC50 value was 248.35 μg/mL, 459.56 μg/mL and 301.20 μg/mL, individualy. Supercritical CO₂ extract of pine pollen had inhibition effects on the lung cancer cells 95D of pig and the s_{Subscript text}tomach cancer cells SGC-7901 of human, and the corresponding active compounds were different.

Abstract: In China, there is a vast area of tobacco producing, and the production condition in various regions is different. It is difficult for the traditional bulk tobacco curing barns with air rising to adjust the area with all conditions, and the intrinsic quality of cured tobacco is difficult to guarantee. We study on a new tobacco curing barn with double-way ventilation, and we analyze its performance through experiments. We tested the change of the temperature field in both the new tobacco curing barn with double-way ventilation and the traditional tobacco curing barn with air rising, the result shows: (1) Air moves in the new tobacco curing barn with double-way ventilation from top to bottom, compared with the traditional bulk tobacco curing barn with air rising, the new tobacco curing barn has a smaller amount of airflow, and it also has a small temperature difference on the same horizontal plane and a reasonable temperature difference on vertical direction, this is good for the curing of different maturity tobacco leaves; (2) Fuel of the new tobacco curing barn with double-way ventilation is one-time added, so the heat supply is stable, and the temperature changes quite gentle, but fuel of the traditional tobacco curing barn with air rising is many-time added, the temperature changes dramatic. (3) The new tobacco curing barn with double-way ventilation has forced ventilation channel and enhanced moisture channel to strengthen the ability of natural ventilation, so when power outages and other emergency situations happen, there is natural air convection in the tobacco curing barn, but the simple tobacco curing barn with air rising totally could not avoid the harm caused by power outages and other emergency situations. This research could provide reference for the design and application of new curing barn later.

Abstract: This study examined extraction of noni (Morinda citrifolia L) seed oil（NSO） by using supercritical carbon dioxide (SC-CO₂). Response surface methodology (RSM) was used to evaluate the effects of the process parameters, namely extraction pressure, temperature and CO2 flow rate and extract time on the yield of NSO. The extraction parameters were optimized with a central composite design experiment. The result showed that the oil recovery got the highest for 20.13% dry basis under the condition of pressure 21 MPa, temperature 37°C, flow velocity 20 L/min and the extract time 104 min, the pressure expressed most significant effect on the oil yield (p <0.001)

Abstract: The Mercenaria mercenaria protein hydrolysates (MMPH) and Ruditapes philippinarum protein hydrolysates (RPPH) were prepared by three enzymatic methods, and the radical scavenging activity of the protein hydrolysates was analyzed. The results showed that the protein hydrolysates prepared by the combination of Protamex and Flavourzyme exhibited significant radical scavenging activity; For DPPH radical, the EC₅₀ values of MMPH and RPPH were 33.0 mg/mL and 93.0 mg/mL, respectively, and for hydroxyl radical, the EC₅₀ values of the protein hydrolysates were 7.5 mg/mL and 7.0 mg/mL, respectively; The protein hydrolysates were further fractionated by ultrafiltration membrane of 6000 Da, and the radical scavenging activity of the resultant fraction with lower molecular weight (<6000 Da) was significantly (P<0.05) increased, and for DPPH radical, the EC₅₀ values of MMPH and RPPH fractions were 29.5 mg/mL and 58.5 mg/mL, respectively, and for hydroxyl radical, the EC50 values of the fractions were 6.0 mg/mL and 7.0 mg/mL, respectively.

Abstract: Extracting Ferulic Acid from wheat bran by ultrasonic-assisted alkaline-alcohol hydrolysis.Bran removed part of starch and protein by amylase and protease,using ultrasonic and different concentrations of alkaline-alcohol solution to prepare ferulic acid,and then based on the yield of ferulic acid release from wheat bran to determine optimal preparation condition.The optimum conditions are:the concentration of sodium hydroxide 4%,alkaline-alcohol volume ratio of 2:1,ultrasonic temperature 80°C,ultrasonic power 200w,solid-to-liquid ratio 1:12,ultrasonic time of 30min,under this conditions the average extraction yield is 3.1mg/g

Abstract: Effects of storage treatments on anthocyanin, fumonisin B1, aflatoxin B1 content of anthocyanin extract from purple corn were evaluated based on the harvest of 2008 and 2009 in north China. The anthocyanin content of anthocyanin extract from husk was 62.4 g/kg, being significant higher than that from cob and seed. The fumonisin B1 and aflatoxin B1 content of anthocyanin extract from the husk were 4.25 and 5.60 μg/kg, respectively, according with legislative limitation of USFDA. Moreover, the fumonisin B1 and aflatoxin B1 content of anthocyanin extract from the husk were lower than the maximum limitation of USFDA after each storage treatments. Therefore, the husk of the purple corn in north China was feasible for anthocyanin production due to its high anthocyanin content and low fumonisin B1 and aflatoxin B1 content.