Advanced Materials Research Vols. 343-344

Abstract: Control of aflatoxin contamination has been a worldwide problem. Laminarin from Laminaria digitata is one kind of polysaccharides with multiple biological activities. In this paper, the inhibitory effects of Laminarin on the growth and toxin production of A. flavus was studied. The results indicated that 150 and 200 µg/mL of Laminarin ccould significantly inhibit the aflatoxin production in Sabouraud liquid medium (Sab), without affecting mycelium growth. In addition, the results also showed that certain concentration Laminaria could decrease the infection of peanut seeds by A. flavus as well as the contamination by aflatoxin B1.

Abstract: The paper studied on parameters of ion implantation into lipid producing strain Rhodotorula glutinis and lipid extration technology. It was found that the strain had a higher positive mutation rate when the output power was 10keV and the dose of N+ implantation was 80×2.6×1013 ions/cm2. Then a high-yield mutant strain D30 was obtained and it’s lipid yield which was 3.10 g/L increased by 33.05% than that of the original. Additionally, statistically-based experimental designs were applied for the optimization of lipid extraction by acid-heating coupling ultrasonic technique. By a Plackett-Burman design, it was found that three factors, treatment time of HCl (p=0.036) , ultrasonic time (p=0.0105) and rate of extracting solution (VCHCl3:VCH3OH) (p=0.0105), had significant effect on lipid extraction. Subsequently, these significant factors were optimized using response surface methodology (RSM), and the optimized parameters of lipid extraction were as follows: 34 min for treatment time of HCl, 7.5 min for ultrasonic treating time, 1.9:1 for rate of extracting solution (VCHCl3:VCH3OH). Finally the fermentation characteristic of high-yield mutation strain D30 was studied, when fermentation time was 10 d, it’s lipid yield increased to 7.81 g/L

Abstract: Based on the theory of flow separate and multi-phase reaction principle, the coupling bioreactor for domestic wastewater reclamation and the sludge reduction was developed in this paper. The results showed that the coupling bioreactor kept stable COD removal efficiency above 85% with the COD loading rate increased from 0.49kgCOD/(m3∙d) to 1.93kgCOD/(m3∙d). Moreover, the excellent effluent quality could be obtained under the condition of Micro-aeration+ Anoxic + Aeration, and the total nitrogen(TN) removal of 86.7% was achieved at HRT of 8h and 43% volume ratio of anoxic zone, meanwhile the effluent TN concentration was lower than 15mg/L and a lower sludge production rate was obtained with mean value of 0.068MLSS/kgCOD.

Abstract: From Chloranthus multistachys, three sesquiterpene lactones, multislactone (1), codonolactone(2), lasianthuslactone A(3), and three diterpenes, 12R,15- dihydroxylabda-8(17), 13E- dien-19-oic acid(4), 12(S),15- dihydroxy labda-8(17), 13E-dien- 19-oic acid(5), 12-oxo-15- hydroxylabda-8(17), 13E-dien-19-oic acid(6) were isolated. The structures of the isolated compounds were established by means of NMR and MS analyses. Compound 1~6 were firstly isolated from this plant. Compound 1 is new natural products. Among them , compound 1 and 6 show anti- inflammatory activities.

Abstract: Gas chromatography coupled with mass spectrometry (GC-MS) was applied to analyze the essential oil extracted from the leaves of 50 individual plants of Cinnamomum camphora, which were collected from the same mountain in Jiangxi province of China. 32 peaks in total were identified in these samples, which were then categorized into five chemotypes (bornel type, BN; camphor type, CP; isoneolidol type, ID; cineole type, CE; linalool type, LN) according to the primary component in the essential oil. In the meanwhile, total DNA was extracted from each sample for random amplified polymorphic DNA (RAPD) analysis, As a result, a total of 97 amplification products derived from 10 RAPD primers were obtained. These RAPD data were then analyzed using SPSS 10.0 software with 1 and 0 matrix, Jaccard’s coefficient and between-group linkage methods. Our results revealed that the estimated Jaccard’s differences between chemotypes varied in the range of 0-25, and that the pattern obtained from RAPD was totally accordant with the identification of GC-MS and the biosynthesis pathways of terpene. Thus, we propose that both GC-MS and RAPD are reliable and useful to identify the chemotypes of Cinnamomum camphora, and that quality control and large-scale cultivation of Cinnamomum camphora are possible.

Abstract: Persimmon has good health function. To further investigate the antioxidant function in vivo, we set up a model mice with ionizing radiation. IRC mice were divided randomly into six groups, Blank control group, Model control group, VE control group, Low dosage group (G1), Middle dosage group (G2) and High dosage group (G3) respectively. Orally given persimmon extract for 35 days, mice were treated with γ-rays. Our results indicated that pervious administration of the persimmon extraction obviously increased the liver index of the mice. And pathological inspection by microscope suggested that orally given persimmon extraction obviously protected the liver cells of the mice. Further analysis demonstrated that persimmon extraction decreased the MDA content, and increased the SOD and GSH-PX activity in both the serum and the liver in the mice after the Ionizing radiation. Our results suggested the protection role of persimmon extraction by inhibiting the oxidation reaction in vivo.

Abstract: A new electrochemical immunosensor for serum myeloperoxidase (MPO) has been developed based on the self-assembly multilays of multi-walled carbon nanotubes (MWNTs), thionine (THI), gold nanoparticles (GNPs) and chitosanon (CHIT) on the glassy carbon electrode (GCE). The antibody of MPO (anti-MPO) was absorbed on the surface of GNPs monolayer. Horseradish peroxidase (HRP) was employed to block non-specific binding and amplify the response current signal. It was observed that the peak current was linear with the MPO concentration in a range of 2.5-125 µgl-1. The detection limit was 1.425 µgl-1 (S/N=3). Correlation analysis showed that this new immunosensor assay has a significant correlation with enzyme-linked immunosorbent assay (ELISA) (r=0.96, p>0.05) for 40 clinical specimens.

Abstract: In order to investigate the reasons for the occurrence of melon disease, according to Koch’s postulates, the pathogenic fungi which caused the disease of postharvest melon“86-1”has been isolated and three kinds of bacterial strain has been identified. By identifying the pathogenicity, results revealed that they are Alternaria sp., Fusarium sp. and Penicillium sp.. They are the major pathogenic fungi which caused the decay of the postharvest Hami melon.

Abstract: The distinction between viable and dead cells was a major issue in detection of pathogenic microbe in foods especially when foods had been subjected to thermal processing. The performance of a loop-mediated isothermal amplification (LAMP) assay with aid of ethidium monoazide (EMA) for detecting viable Escherichia coli O157 in raw milk was presented in this paper. Three pairs of primers were specially designed for recognizing eight distinct sequences of rfbE gene. LAMP can only amplified DNA of viable Escherichia coli O157 because EMA selectively penetrated dead cells and covalently bound to DNA, detection limit level for artificially contaminated raw milk samples by the EMA-LAMP assay was 440 cfu/mL corresponding to 3–5 cells per reaction tube, while the detection level by EMA-PCR was 4.4×104 cfu/mL. In conclusion, EMA-LAMP had offered a novel assay for distinction between viable and dead cells with promising application in food safety detection.

Abstract: Galactose is found in many oligosaccharides, galactomannans, glycoproteins and glycolipids, which are widely distributed in plants microorganisms and animals. α-Galactosidase (α-Gal) catalyzes the hydrolysis of 1,6-linked α-galactosyl residues and transgalactosylation. α-Gals are classified into four glycoside hydrolases families (GH): 4, 27, 36 and 57. The majority of known α-Gals belongs to GH families 27 and 36.α-Gals are of particular interest in view of their biotechnological applications.