Advanced Materials Research Vols. 610-613

Abstract: The purpose of this study was to select the optimum ultrasound-assisted extraction (UAE) conditions for the extraction of polysaccharides from Pleurotus eryngii (DC. ex Fr.) Que (P. eryngii ). The main factors that affect the extraction yield of polysaccharides such as solid:liquid ratio, ultrasonic power, extraction time and extraction temperature were studied individually. An orthogonal experiment was designed to optimize the extraction parameters. It was found that UAE method was a reliable, simple and effective method for fast extraction of polysaccharides from P. eryngii. The optimum UAE conditions were as followings: Solid:liquid ratio of 1:35, Ultrasonic power of 55 W, Extraction time of 30 min and extraction temperature of 45°C.

Abstract: Planting in mountain land and sloping fields，production of coffee is restricted by drought and undernutrition, therefore scientific mode of water and fertilizer is the basis guarantee of high quality and yield. To seek quantitatively optimized decision of irrigation and fertilizer of coffee in tropical and subtropical district, perfect the theory of efficiency use of water and fertilizer in coffee, and realize ecological agriculture developing target of high quality and yield, this paper summarizes the effect of water and fertilizer on growth, physiological characteristic, yield and quality, and put forward some scientific questions need to be further studied such as pattern of water consumption and optimization management of water and fertilizer under water saving irrigation.

Abstract: Fresh fruits and vegetables are rich sources of nutrients and phytochemicals for health. Thus, consumer has increased the demand for them, particularly blueberries. Two varieties of cultivated blueberries and a wild blueberry (Vaccinium uliginosumL.) were selected in order to determine their antioxidant activity as related to their anthocyanins. Anthocyanin content of different varieties of blueberries was determined by pH differential method. Anthocyanins from different varieties blueberries were assayed for their antioxidant properties in vitro systems, including inhibiting activity on lipid peroxidation, scavenging activity on hydroxyl radical, superoxide anion radical and DPPH radical. The results showed that anthocyanin content of wild blueberry was the highest and anthocyanin content of Northland blueberry was the lowest among different varieties blueberries. Blueberries anthocyanins were effective antioxidants, and there was a dose-dependent relationship between anthocyanins content and antioxidant activity. The overall antioxidant capacity ranked on the order of Blomidon blueberry>wild blueberry>Northland blueberry. The result also showed that antioxidant property was not only correlated with anthocyanins content but also related to their composition and structure. Blueberries anthocyanins was a rich source of natural antioxidant and potential used as a food additive.

Abstract: In order to study the effects of power plant thermal discharge on phytoplankton in different temperature rise. Mesocosm experiment has been done in Guohua plant near the Xiangshan Bay in July 2011. The variances of the water-quality index such as Chlorophyll a, DO, COD and nutrients were analyzed. The results shown that relative to the control area M3,the Chlorophyll a in M1 ( increased 0.8°C) decreased by 45%, while the M2 (increased 0.4°C) increased by 26%, thus, this paper comes to the conclusion that exotherm exceed 0.8°C cause harm on phytoplankton growth, and exotherm that is lower than 0.4°C cause little effect. The experiment found that the COD, DO and Chlorophyll a were positive correlation; nutrients and chlorophyll-a were negative correlation, these indicators can be used as auxiliary indicators in the damage assessment of the thermal discharge for phytoplankton.

Abstract: The influence of the mowing agronomic measure on the quality of Saussurea involucrata was studied in Urumqi, Xinjiang using the method of combining biotechnology with botany, in order to reveal the effect of mowing strength on flavonoids and polysaccharide content in S. involucrata. The results show that S. involucrata has strong regeneration ability after mowing and it can be mown four times in a year. And the flavonoids content decreases while its polysaccharide content increases generally under different mowing times. In addition, the flavonoids content decreases in general, while its polysaccharide content reduces at first and then greatly increases with mowing frequency increases at the same study area. However, their flavonoids content meets medicinal quality standards of pharmacopoeia of the People's Republic of China in 2010 (flavonoid≥0.15％). For S. involucrate with longer growth period in whole life, it can get higher production of chemical composition by mowing. The results have important application value in production practice. It can provide a case of mowing scheme for the sustainable efficient use and quality control for the medicinal materials of S. involucrate.

Abstract: Numerical simulation and experimental study on the extraction of oil from red pepper seed using supercritical CO2 was performed in this study. Some main influence factors were investigated, including the influence of operation pressure and temperature on extraction yield Xe(%). A model equation was established based on mass transfer process, and the model equation was validated with the experimental data. The maximal and minimal relative errors between experimental data and numerical simulation value were 1.29% and 0.28% respectively. The results of 3-D simulations were obtained by associating extraction yield Xe(%) with operation temperature and pressure. As shown in the figures, it is obvious that there is an excellent agreement between the correlations results and the experimental data. Consequently, the optimum pressure and temperature were determined to be 20MPa and 318K respectively.

Abstract: The five extracts from Allium cepa L. var. agrogatum Don (ACAD) were determined for their total antioxidant activity by T-AOC kit. The highest antioxidant capacity of the extracts was ethanol fraction. Then the ethanol extracts were purified by AB-8 resin column and polyamide resin column successively. The refined samples were analyzed with HPLC by comparing with quercetin. Moreover, three different methods was selected for evaluating the antioxidant capacity of the reduction of scavenging activity of the stable DPPH radical, the hydrogen peroxide and superoxide anion O2-•radical.Results shown that ACAD exhibited the highly efficient antioxidant activity in all the studied. Thus the results indicated that it could be used as functional food and antiatheroscloresis products.

Abstract: Research had been carried out on the technology of separating resveratrol and catechin extracted from the peanuts skin. The macroprous adsorption resin AB-8 had been selected from 3 kinds of carriers by static adsorption and deadsorption test. The single factor tests and response surface experiments had been applied to optimize the enrichment and separation condition of resveratrol and catechin. The optimum adsorption conditions were as follows: feeding rate 2mL/min, pH 6.0 with the concentration of resveratrol and catechin to be 2µg/mL and 0.5mg/mL respectively. The optimum elution conditions were elution rate 1.5 mL/min and pH5.0. Resveratrol and catechin could be purified and separated by different conditions. Resveratrol was eluted by 20% ethanol while catechin by 60% ethanol. After concentrating and drying, the contents of resveratrol and catechin were 49.63% and 91.07%, respectively.

Abstract: Aflatoxin B₁ (AFB1), as a kind of mycotoxin produced by Aspergillus spp., is a highly toxic substance and widely distributed in food matrix. Cumarin was used first as the only carbon and energy source to screen the strains which were separated from different kinds of food. The strains selected were then added into nutrient agar and broth media to assess the ability to deplete AFB1. Results showed that a strain isolated from mustiness foodstuff was able to degrade AFB1 in nutrient broth, with a degradation rate of 26.3% after 48h fermentation. The microorganism was identified as a strain of Aspergillus niger, with analysis of phylogenetic tree based on 18S rDNA. This provides a potential solution for biological degradation of AFB1.

Abstract: This paper carried research on seed rain intensity, seed rain time, the effects of sound seed input density of Castanopsis fargesii population and Castanopsis carlesii population in the Three Gorges Reservoir. The result showed that: (1) the seed production of Castanopsis carlesii and Castanopsis fargesii was low in the studied population, the seed rain was 36.5 seeds • m-2, 22.6 seeds • m-2, and the sound seed input density were 20.5 seeds • m-2, 9.6 seeds • m-2 respectively. (2) infesting and decay were the main causes of seed losing, 43.8% lost in Castanopsis carlesii population and 67.5% lost in Castanopsis fargesii population. (3) the duration of Castanopsis carlesii and Castanopsis fargesii population’s seed rain were 47days and 37 days, but there was a different top time between two populations, the seed rain peak of Castanopsis carlesii population was from middle to late November, with a distinguishable dropping peak, and the seed rain peak of Castanopsis fargesii population was from early to middle November.(4) temperature has significant effect on sound seed input density of Castanopsis carlesii population, temperature and wind speed have significant effect on sound seed input density of Castanopsis fargesii population.