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1.
采用同轴静电纺丝技术将蛛丝蛋白(Ss)和美洲大蠊提取物(PAE)分别负载于纳米纤维的壳层与核层。随着Ss的增加,纤维直径从350 nm降至280 nm,核层直径由120nm升至140 nm,壳层厚度由115 nm降至70 nm。Ss的加入使纳米纤维膜具有良好的机械性能和亲水性,纳米纤维膜的拉伸强度可达到4.31 MPa,溶胀率可达到150%,水蒸气透过率可达到1834 g/(m2?24h),水接触角减小到 32.7 ?。纳米纤维膜核壳结构能够有效抑制药物突释,实现药物长效释放,7天内药物释放可达77%;纳米纤维膜能够有效抑制细菌生长,促进细胞增殖,相较于未负载Ss的纳米纤维膜,负载20%Ss的纤维膜的细胞增殖效果提高25%,说明Ss和PAE在伤口愈合过程中能够起到协同作用。  相似文献   
2.
The biological activities of synthetic periplanone analogs, including four candidates of periplanone-A (P-A), were evaluated by behavioral and electroantennogram (EAG) assays. Among 16 periplanone analogs, six compounds evoked pheromonal activity from the male American cockroaches. The threshold dosages of these biological active analogs were 10–105 times lower than that of the known periplanone mimic, germacrene-D. The conformation required for eliciting the pheromonal activity is discussed in terms of the structure-activity relationship of these analogs. Hauptmann's P-A elicited the strongest pheromonal activity among four candidates of P-A in our bioassay, suggesting that Hauptmann's P-A is a natural P-A produced from female cockroaches.  相似文献   
3.
The significance of the alkyl group at the C-4 of (+)-trans-verbenyl acetate, which is the sex pheromone mimic of the American cockroach, was investigated. Seven alcohols possessing an ethyl, propyl, or dimethyl group at this position of the 6,6-dimethylbicyclo[3.1.1]heptane skeleton were synthesized and evaluated by behavioral assay. All of the alcohols were inactive, while three of four acetates of the 2-alcohols induced sexual behavior in male cockroaches at the 0.02 or 0.5 mg dosage level, either of which is many orders of magnitude higher than the threshold level of the natural sex pheromones (10–8 mg). Among the acetates, the compounds with a methyl group or an -oriented ethyl group at C-4 showed the highest activity. The results are discussed in terms of spatial requirements of the molecules for interactions with the receptor.Studies on the sex pheromone mimic of the American cockroach, (+)-trans-verbenyl acetate. Part VIII. For Part VII, seeComp. Biochem. Physiol.,70A: 229–234 (1981).  相似文献   
4.
From the relationship between structures of the 2-substituents of verbanyl analogs and their sex pheromone activities to the American cockroach, electron density of the carbonyl oxygen atom in the substituent, as estimated by the [17O]NMR chemical shift, was estimated to be an important factor which influenced the activity, in addition to length of the substituent and the position of the carbonyl group. (+)-Verbanyl methylcarbonate (XX), possessing the highest electron density on the carbonyl oxygen atom, showed the strongest activity among the analogs.For Part X, see Manabe et al., 1983. J. Chem. Ecol. 9:533–549.  相似文献   
5.
Electrochemistry of malePeriplaneta americana perception of naphthoquinones as allelochemicals is presented. Importance of the oxidation-reduction potential and hydrogen-bonding capabilities of the naphtho-quinone messenger to its exchange of energy with the information-encoding, redox protein of the chemosensory neuron is considered. Evidence that the required information is initially encoded by an electroreactive protein in dendritic membrane is analyzed. A sulfhydryl-disulfide protein-based electrochemical mechanism for the demonstrated linear conversion of a molecular messenger energy state into whole insect behavior (avoidance or feeding inhibition) is elucidated. Even though the information-encoding mechanism is genetically conserved (kept electrochemically similar) within the species, behavioral biotypical differences regarding sensitivity to naphthoquinones are allowed through a group of proteins in the outer aqueous medium in the chemosensory sensillum. Such proteins electrochemically interface the dendritic membrane of the chemosensory neuron in the sensillum with the environment external to the sensillum. These interfacing proteins bind (complex) with chemical messengers (e.g., naphthoquinones) and/or variously degrade them, and thus determine the amount (moles) that is required in the environment to result in stimulation of the underlying sensory neurons and in a changed behavior.  相似文献   
6.
Bioassays were performed on malePeriplaneta americana L. using synthetic (–)-periplanone-B (P-B) and Hauptmann's (–)-periplanone-A (P-A), and their mixtures at various ratios to estimate the roles of both periplanones for the sexual communication of the species. Both P-A and P-B elicited qualitatively the same responses, such as antennal movement, rapid locomotion, wing raising, and homosexual behavior of male cockroaches, but the threshold of the pheromone activities for P-B was two orders of magnitude lower than that of P-A. Neither synergistic nor inhibitory but only a simple integrated effect on the responses was observed when mixtures of P-A and P-B were applied.  相似文献   
7.
The attractivity of virgin female odors of the American cockroach was examined in field experiments. Crude extracts of the female odor, the isolated sex pheromone fractions, periplanone-A and periplanone-B, and other compounds obtained during the isolation served as stimulants. An extract of male odors, obtained by identical collection methods, was used as a control. Males ofPeriplaneta americana were attracted by the crude extract and periplanone-B; males of the sympatric species,P. Australasiae, by periplanone-A. Experiments in which these components were presented subsequently and as mixtures indicate that, under certain conditions, periplanone-A may also function as an attracting substance forP. americana males and that periplanone-B and possibly some other components act as an inhibitor for males ofP. australasiae.  相似文献   
8.
为确定美洲大蠊成虫油脂的提取方法、性质及脂肪酸构成,为其利用奠定基础,采用响应曲面对超声波-微波提取美洲大蠊油脂条件进行优化,分析了油脂的热力学性质、脂肪酸构成及理化指标。结果表明,美洲大蠊成虫油脂超声波-微波法提取的最佳条件是时间5 min,液料比10∶1,超声波功率321.35 W,微波功率179.84 W,温度50.07℃,理论得率为31.00%,实际得率为30.65%。GC-MS检测到13种脂肪酸,棕榈酸、油酸、亚油酸为主要成分,占总脂肪酸的77.02%,含量分别为70.47、36.49、81.38 mg/g。不饱和脂肪酸含量高,占总脂肪酸的71.49%。油脂RGB颜色的饱和度(HIS)S为0.67,偏黄色,油脂的碘值为128.11g/100 g、酸值为8.73 mg/g、过氧化值为1.10 mmol/kg、皂化值为407.17 mg/g、熔点为3.56℃,结晶点为-36.37℃。油脂品质较好,可以作为潜在的食用油脂来源。  相似文献   
9.
10.
The sex pheromone of the American cockroach,Periplaneta americana, consists of two compounds, which we have named periplanone-A and periplanone-B. The two compounds can be isolated from fecal material in a ratio of 110, and periplanone-B can also be isolated from intestinal tracts. A total amount of 200 g of periplanone-B has been isolated from both fecal material and alimentary tracts. By means of gas chromatography-mass spectrometry, hydrogenation, infrared analysis, and NMR analysis, we were able to identify periplanone-B as (1Z,5E)-1,10(14)-diepoxy-4(15),5-germacradien-9-one. The overall structure was confirmed by comparison with a synthetic, biologically active epimer of periplanone-B.  相似文献   
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