Applied Mechanics and Materials Vol. 108

Abstract: A series of novel Hydroxylated 9,10-anthraquinone derivatives were designed and synthesized as potential antitumor agents starting from the natural product Emodin. The structures of the compounds were identified by NMR, ESI-MS and elemental analysis. Their antitumor activities against KLE cell line were tested by MTT assay. Some of them were found to exhibit a cytotoxicity profile more potent than Emodin on KLE cell line.

Abstract: In the study, the Mx gene promoter, exon 1, exon 2, and exon 14 and intron 13 in eight Chinese local chicken breeds were examined. Amino acid 631 in the GED region was tested in eight Chinese local chicken breeds and two exotic breeds. The frequency of allele A was 0.1259 and the frequency of allele G was 0.8741. Meanwhile, induction of expression of the Mx gene in chicken embryo fibroblasts was analyzed in the local chicken breed, Beijing-you and the exotic breed, White Leghorn.The semi-quantitative and quantitative results showed that the expression of the Mx gene in White Leghorn was significantly different under different induction conditions. There was also a difference in the genotypic distribution of S631N in two breeds: allele A/G was 0.8471/0.1529 and 0.1613/0.8387 in White Leghorn and Beijing-you chickens, respectively. We speculate that the difference in the genotypic distribution has an effect on Mx gene expression.

Abstract: .Adult Tessaratoma papillosa (Drury) (Hemiptera: Pentatomidae) secreted volatiles from metathoracic glands (MTG). Behavior and olfactory responses of adult bugs to their MTG secretions were tested using a Y-tube olfactometer and an electroantennogram (EAG). The results indicated that males were obviously attracted by female secretions and repelled by male secretions. Secretions of adult males elicited the greatest response of male antennae, whereas the lower response of male antennae to MTG secretions of adult females was recorded. The four compounds, (E)-2-octenal, undecane, dodecane and tridecane were tested for the EAG activity and behavior response with male adults at different concentrations. In EAG assays, the antenna of male T. papillosa showed the highest sensitivity to (E)-2-octenal (10 μL /μL) and the second highest sensitivity to undecane (10 μL /μL), but a similar sensitivity to other stimuli. Unlike EAG results, males were attractive to (E)-2-octenal (10^-2 and 10^-1 μL /μL) and tridecane (10 μL /μL), and repelled by (E)-2-octenal (10^-3, 1, 10 and 10² μL /μL) and tridecane (10^-1 μL /μL) in the Y-tube olfactometer. Our data suggested that (E)-2-octenal and tridecane may be part of a complex pheromone system in T. papillosa.

Abstract: Natural gas of Tazhong-1 gas field contains 7.7% carbon dioxide and 2.31% hydrogen sulfide, and produced water salinity is up to 140000mg/L,the well-bore tube has seriously potential corrosion destructive with natural gas being exploited. Based on the corrosion type partition of down-hole tube for eighteen production wells of Tazhong-1 gas field, P110,P110S and P110SS corrosion behavior were investigated under the conditions of simulated formation water containing carbon dioxide or hydrogen sulfide/carbon dioxide, and corrosion inhibitors were chosen to meet need of anticorrosion of Tazhong-1 gas field. The results show that fifteen wells in eighteen production wells belong to hydrogen sulfide corrosion of both hydrogen sulfide and carbon dioxide influence. Other wells are singular carbon dioxide corrosion. The most severe corrosion of three types of down-hole tubes all occurs at 90°C in both corrosion media, and their corrosion resistance order is respectively P110>P110S>P110SS and P110S>P110SS>P110 under the conditions of simulated formation water containing carbon dioxide or hydrogen sulfide and carbon dioxide. The selected anti-temperature corrosion inhibitors (YU-1、YU-4) can control the corrosion rate of three types of down-hole tubular goods within 0.076mm/a in simulated formation water media with carbon dioxide (P_CO2=0.08～4.64MPa) or hydrogen sulfide and carbon dioxide (P_H2S/Pco₂=1.3/4.64Mpa) while added amount of the inhibitor is 120～300mg/L or 200mg/L. All of these provide technical support for safe and fast development of Tazhong-1 gas field.

Abstract: Two species of bamboo, Phyllostachys edulis and Phyllostachys aureosuleata (including 4 cultivars for each of the species) are known to have significant amounts of phenols and flavonoids, and exhibit a strong antioxidant activity. Experiments were conducted to examine the variation in the contents of total phenols and flavonoids, and antioxidant activities in the shoots and shells. The result showed that the hightest contents of total phenols and total flavonoids were P. aureisykeata cv. Spectabilis and P. edulis cv. Heterocycla, respectively. The antioxidant activities were determined by DPPH(scavenging assays of DPPH radicals). Among all of the shoots samples analyzed, the P. aureisykeata cv.Spectabilis showed the best performance in scavenging assays of DPPH radicals. Among the shells, the P. edulis cv. Heterocycla showed the best performance. In addition, significant correlations were found between the contents of total phenols and flavonoids and DPPH radical scavenging activity. This work indicated that ethanol extracts of shoots and shells from eight cultivars bamboo exhibited stronger antioxidant activities compared with those of the commercial compound (Trolox). It might be considered as a potential rich sources of natural antioxidants.

Abstract: The volatile oil of the four different bamboo leaves from Phyllostachys violascens cv.notata, Sinobambusa tootsik (sieb.) Makino, Sasa subglabra McClure and Pleioblastus kongosanensis f.aureostriaus was obtained by steam distillation; their chemical components were separated and identified by gas chromatography-mass spectrometry (GC-MS). The relative percentage content of the components from the volatile oil was determined by area normalization method. The DPPH free radical scavenging activity (IC₅₀) of the volatile oil was tested by the use of Trolox as a control. The experimental results show that there are 15 kinds of compounds which all simultaneity contained in the volatile oil of four different provenances of bamboo leaves. In four different provenances of volatile oil of bamboo leaves, the relative content of eugenol was obviously higher than other components, were 38.47%, 48.73%, 35.85% and 18.40% respectively. The relative content of the total phenolic were 51.96%, 51.78%, 40.06%, 22.81% respectively. The four different bamboo leaves volatile oil all have the ability of scavenging DPPH free radical and the IC₅₀ are 1.16 mg/ml, 1.44 mg/ml, 1.57 mg/ml, 1.71 mg/ml, respectively. The antioxidant activity of the essential oil has a positive correlation with the essential oil's concentration. The result of the experiments can provide reference for further research on the chemical components of different bamboo leaves volatile oil as well as for the exploration and utilization of it.

Abstract: Taxus media is the natural hybrid variety of Taxus cuspidate and Taxus baccata, and has been used as an anticancer plant with some medical components-taxanes. In this study, ultra performance liquid chromatography was used for quantification of three major bioactive taxanes in Taxus media, which were collected in Zhejiang province and Sichuan province (China). As a result of this study, a convenient, accurate, rapid and reproducible UPLC method has been developed to successfully quantify 10-Deacetylbaccatin Ⅲ (10-DABⅢ), Cephalomannine and Taxol in the needle and twig of Taxus media. The results indicate that the sequence of the contents of three active components in Taxus media with different parts was needle>twig; the sequence of the contents of three active components in Taxus media with different growth years was 5 year old >4 year old >3 year old; and there were great differences in the contents of three active components in Taxus media between Zhejiang province and Sichuan province. The results also provided a scientific basis for uses of Taxus media.

Abstract: Preliminary results of petri dish bioassay showed that n-hexane and ether extracts of body surfaces of female and male Tessaratoma papillosa (Drury) were significantly attractive to the opposite sex and the same sex respectively. EAG results also demonstrated that both two kinds of solvent extracts could induce the EAG responses of adult T. papillosa. Sixteen components were identified and isolated from the extracts of adult T. papillosa body surfaces by gas chromatograph-mass spectrometer (GC-MS), of which tridecane was the common component of females and males and had the highest relative amount. In addition to three kinds of straight-chain alkanes which were undecane, dodecane and tridecane, there were other components such as (Z)-2,2-dimethyl-3-hexene, 2-hexen-1-ol acetate, (E)-2-hexen-1-ol acetate, 2,3,3-trimethyl-1-butene and 1-tridecene and others.