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1.
Codling moth, Cydia pomonella (L.), is a severe pest of apples, pears, and walnuts worldwide, and new approaches for precise monitoring and management would be beneficial. Ninety-two pome fruit volatiles were formulated in 23 distinct blends, of which a single 4-component blend of 10-carbon esters showed the only significant attraction of moths in field bioassays conducted in both walnut and apple orchards. A single constituent of this blend, ethyl (2E,4Z)-2,4-decadienoate--the "pear ester", was the major contributing attractant. The pear ester attracted both male and female moths in combined numbers that were comparable to the attractiveness of conspecific sex pheromone. Structure-activity tests were conducted in a series of orchard trials to determine the specificity of attraction of codling moths to the pear ester kairomone. No analogue 10-carbon alcohols, aldehydes, acetates, or other esters elicited significant moth capture responses. Tests with various analogue esters with alcohol chain length moiety substitutions of the (2E,4Z)-2,4-decadienoic acid elicited differential capture responses, with the ethyl exceeding the propyl, methyl, butyl, and hexyl analogues. The (E,Z) geometric isomers of this series of (2E,4Z)-2,4-decadienoic acid esters far exceeded the attractiveness of the (E,E) isomers. The pear ester is a potent attractant of both males and females, and codling moths are highly discriminating and specific in their structure-activity-based attraction to this pear-derived kairomone. These specificity attributes should allow this host plant kairomone to contribute to new abilities for female monitoring and the potential of development of novel and highly selective control practices that should decrease the current dependence on the use of broad-spectrum insecticides. 相似文献
2.
Ester variability in apple varieties as determined by solid-phase microextraction and gas chromatography-mass spectrometry 总被引：2，自引：0，他引：2
Solid-phase microextraction (SPME) with a polydimethylsiloxane fiber coupled with gas chromatography-mass spectrometry (GC-MS) was applied to the study of variability in volatiles released by 13 apple varieties. The relative amounts of 40 esters and alpha-farnesene were determined. Principal component analyses of these results clustered the apples into three groups according to skin color: red, green, and red-green. Total ester contents were highest with the red cluster apples, and the green cluster apples had the highest alpha-farnesene levels. This technology was also applied to the monitoring of changes in volatiles for apples removed from controlled-atmosphere storage with subsequent storage at 4 degrees C and room temperature. Total ester contents increased 25-fold, with the greater increases coming at room temperature, whereas alpha-farnesene levels increased only 5-fold. For apples stored at room temperature, after 11 days, the amount of increase was inversely proportional to the size of the ester: levels of smallest esters (molecular weight 116) increased 12.5-fold, and the largest esters (molecular weight 228) increased approximately 1.3-fold. 相似文献
3.
Buttery RG Light DM Nam Y Merrill GB Roitman JN 《Journal of agricultural and food chemistry》2000,48(7):2858-2861
Volatiles were isolated from whole green mature walnuts (Hartley variety) with husks still intact using dynamic headspace sweeping with trapping on Tenax. A total of 45 volatile compounds were identified by GC-MS. Major volatiles identified included (E)-4, 8-dimethyl-1,3,7-nonatriene, pinocarvone, pinocarveol, myrtenal, myrtenol, (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, caryophyllene epoxide, verbenol, verbenone, and terpinolene. Green walnuts that had been infested with codling moth showed appreciably higher amounts emitted for (E)-4,8-dimethyl-1,3,7-nonatriene, (E, E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene, alpha- and beta-pinenes, sabinene, (E)-beta-ocimene, (E,E)-alpha-farnesene, and linalool. The infested nuts also emitted benzyl methyl ether, isobutyl cyanide, and 1-nitro-3-methylbutane, compounds not found with the healthy nuts. Volatiles from uninfested green walnuts at the maturity stage where the husk was just beginning to split were also analyzed and compared. 相似文献
4.
Cloudy apple juice has been found to develop off-flavors during storage in daylight. The development of off-flavors and volatile compounds was monitored in reconstituted juice prepared from 'Golden Delicious' and 'Fuji' apple concentrates stored in glass bottles under fluorescent light (3000 lx, 8 degrees C). A strong metallic off-flavor was formed by photooxidation. A major contributor to the off-flavor was identified as 1-octen-3-one by gas chromatography-olfactometry. In addition, six volatile compounds, pentanal, 2-methyl-1-penten-3-one, hexanal, (E)-2-heptenal, 6-methyl-5-hepten-2-one, and (E)-2-octenal, increased significantly after light exposure and could contribute to the off-flavor. Except for pentanal and hexanal, these volatiles were found only after light exposure. Higher levels of volatiles were observed in juice from 'Golden Delicious' apples than in juice from 'Fuji' apples, and this difference was consistent with higher levels of suspended solids. When the suspended solids were removed by centrifugation, the development of volatiles on exposure to light was reduced significantly. 相似文献
5.
Wei S Reuveny H Bravdo BA Shoseyov O 《Journal of agricultural and food chemistry》2004,52(20):6212-6216
Glycosidically bound volatiles released from apple leaf extracts (cv. Anna) were analyzed by solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and their behavioral effects on codling moth (CM) adults were evaluated in cage bioassays. The levels of 1-octanol, linalool, geraniol, benzyl alcohol, methyl salicylate, (2R,5R)-theaspirane, and (2S,5R)-theaspirane were significantly increased in the leaf extracts containing the Aspergillus niger beta-glucosidase (BGL1) compared to the extracts containing the glucoimidazole. The attractiveness of individual compounds to CM adults was found in the following decreasing order: methyl salicylate and mixture of two theaspirane isomers, followed by linalool and benzyl alcohol. Geraniol was found to be repellent to CM adults. The addition of geraniol (39.4 ng mL(-1)) to any of the individual volatiles or to a mixture of these attractants eliminated their attractiveness. Our data suggest the possible application of geraniol as a repellent and methyl salicylate or theaspiranes as attractants for the integrated control of CM in apple orchards. 相似文献
6.
Odors in the headspace of apple trees were characterized by in situ volatile collections in the orchard. Sixty-two compounds were quantitatively identified with thermal desorption-gas chromatography-mass spectrometry over the complete fruit-growing season. Overall quantities in the headspace of fruit-bearing twig were highest at petal fall and at the beginning of June and August. Interestingly, the latter two periods coincide with the flight maxima of the codling moth, Cydia pomonella, one of the principal pest insects of apple fruit worldwide. Dual-choice bioassays with mated adult female moths in a Y-tube olfactometer showed that the blend of plant-derived volatiles repelled this key pest of apple at petal fall and attracted it from July to mid-August. Single-component analysis indicated that benzaldehyde and butyl acetate might contribute to the observed repellent effect, but the constituents accounting for the attractant effect mid-season remain to be further elucidated. The attractant effect clearly originates from the apple fruit and not from the twig with leaves, as bioassays demonstrated conclusively. 相似文献
7.
Cashew apple nectar is a secondary product from the production of cashew nuts and possesses an exotic tropical aroma. Aroma volatiles in pasteurized and reconstituted (from concentrate) Brazilian cashew apple nectars were determined using GC-MS and split, time-intensity GC-olfactometry (GC-O)/GC-FID. Methional, (Z)-1,5-octadien-3-one, (Z)-2-nonenal, (E,Z)-2,4-decadienal, (E,E)-2,4-decadienal, beta-damascenone, and delta-decalactone were identified for the first time in cashew apple products. These compounds plus butyric acid, ethyl 3-methylbutyrate, 2-methylbutyric acid, acetic acid, benzaldehyde, homofuraneol, (E)-2-nonenal, gamma-dodecalactone, and an unknown were the most intense aroma volatiles. Thirty-six aroma volatiles were detected in the reconstituted sample and 41 in the pasteurized sample. Thirty-four aroma active components were common to both samples. Ethyl 3-methylbutyrate and 2-methylbutyric acid were character impact compounds of cashew apple (warm, fruity, tropical, sweaty). Using GC-pFPD, 2-methyl-3-furanthiol and bis(2-methyl-3-furyl) disulfide were identified for the first time in cashew apple. Both were aroma active (meaty). 相似文献
8.
Himanen S Vuorinen T Tuovinen T Holopainen JK 《Journal of agricultural and food chemistry》2005,53(22):8624-8630
Volatile emission profile of strawberry (Fragaria x ananassa Duch.) plants (cvs. Polka and Honeoye) damaged by cyclamen mite (Phytonemus pallidus Banks) or leaf beetle Galerucella tenella (L.) (cv. Polka) was analyzed to determine the potential of these strawberry plants to emit herbivore-induced volatiles. The total volatile emissions as well as emissions of many green leaf volatiles (e.g., (Z)-3-hexen-1-ol and (Z)-3-hexenyl acetate) and methyl salicylate were greater from cyclamen mite-damaged strawberry plants than from intact plants. Leaf beetle feeding increased emissions of monoterpenes (Z)-ocimene and (E)-beta-ocimene, sesquiterpenes (E)-beta-caryophyllene, (E,E)-alpha-farnesene, and germacrene-D, and a homoterpene (3E)-4,8-dimethyl-1,3,7-nonatriene (DMNT) significantly. Nevertheless, the na?ve generalist predatory mites, Neoseiulus cucumeris, Neoseiulus californicus, and Euseius finlandicus did not prefer P. pallidus- or G. tenella-damaged plants over intact plants in a Y-tube olfactometer, suggesting that these predatory mite species are not attracted by the herbivore-induced volatiles being released from young strawberry plants. 相似文献
9.
Headspace analyses of pollen, whole flowerheads, ligulate and tubular florets, flower buds, involucral bracts, and leaves have been performed on the food plant Chrysanthemum coronarium L. (Asteraceae). The analyses permitted differences in the pattern of volatiles emitted by the different floral parts to be observed and the site and phenological stage of emission of these chemicals to be verified. Camphor and cis-chrysanthenyl acetate were emitted mainly by ligulate and tubular florets; the production of myrcene and (Z)-ocimene was higher in the flower buds, whereas beta-caryophyllene, (E,E)-alpha-farnesene, and (E)-beta-farnesene seemed attributable mainly to the involucral bracts. The leaves showed a quite different volatile profile, with (Z)-ocimene as the main constituent. Pollen showed a completely different composition of its volatiles, with perilla aldehyde, cis-chrysanthenyl acetate, and camphor among the principal compounds; many carbonylic compounds and linear hydrocarbons have been detected exclusively in pollen. Furthermore, the essential oils obtained from flowerheads and leaves have been studied. These samples showed mainly quantitative differences. Camphor (22.1%) and cis-chrysanthenyl acetate (19.9%) were the main constituents of the oil from flowers, whereas the oil from the leaves contained mainly (Z)-ocimene (45.4%) and myrcene (28.2%). 相似文献
10.
为了探明茶叶挥发物在鞍形花蟹蛛(Xysticus ephippiatus Simon)搜寻猎物——茶尺蠖(Ectropis obliqua Prout)过程中的作用,采用固相微萃取气相色谱质谱联用技术研究了茶尺蠖取食对茶树叶片挥发物释放的影响,并通过蜘蛛行为观测平台研究了蟹蛛在不同味源侧(觅食斑块)的活动行为。结果表明:对照叶片没有释放出挥发物,经茶尺蠖幼虫取食后的叶片能释放31种挥发物,其中有12种绿叶挥发物、9种萜类及其衍生物、4种芳香族挥发物和6种未知化合物。行为观测表明,雌、雄蟹蛛进入处理味源侧(茶尺蠖取食后的茶树叶片)和对照味源侧(未损伤茶树叶片)的初次选择均不存在差别(P>0.05),雌蛛进入处理味源侧和对照味源侧的频次分别为3.37±0.18和3.43±0.15,二者无明显区别(P>0.05);雄蛛进入两侧的频次分别为3.86±0.21和3.66±0.20,也无明显区别(P>0.05);雌蛛在处理味源侧和对照味源侧的停留时间分别为(922.57±19.59)s和(818.89±29.63)s,有极显著差异(P<0.01),雄蛛在两侧的停留时间分别为(937.97±18.05)s和(814.83±18.97)s,也有极显著差异(P<0.01),表明雌蛛、雄蛛在处理侧的停留时间明显延长。这说明,猎物取食诱导改变了茶树叶片挥发物的释放,而鞍形花蟹蛛能感知挥发物的变化并由此调整在不同觅食斑块中的停留时间。另外,本文还讨论了挥发物在蟹蛛搜寻猎物过程中的生态学意义。 相似文献
11.
Whitaker BD Schmidt WF Kirk MC Barnes S 《Journal of agricultural and food chemistry》2001,49(8):3787-3792
Hexane extracts of epicuticular wax from cv. Gala apples were noted to have an unusual, broad absorbance maximum at approximately 258 nm, which led us to isolate and identify the primary UV-absorbing compounds. Column and thin-layer chromatography yielded a fraction that gave a series of paired, 260-nm-absorbing peaks on C(18) HPLC. These were shown to be a family of phenolic fatty acid esters, for which retention times increased with increasing fatty acid chain length, and paired peaks were esters of two related phenolics with the same fatty acid moiety. Alkaline hydrolysis of the esters released two water-soluble phenolics separable by C(18) HPLC. Electrospray ionization mass spectrometry gave a molecular mass of 150 for both, and (1)H NMR plus UV absorbance spectra identified them as E and Z isomers of p-coumaryl alcohol. Alkaline cleavage of the fatty acid esters in the presence of methanol or ethanol resulted in partial derivatization of E-p-coumaryl alcohol to the corresponding gamma-O-methyl or O-ethyl ether. Gradient HMQC NMR of the HPLC-purified stearate ester of E-p-coumaryl alcohol indicated that fatty acid esterification occurs at the gamma-OH rather than at the 4-OH on the phenyl ring. This is the first report of fatty acid esters of monolignols as a natural plant product. 相似文献
12.
D D Rowan J M Allen S Fielder M B Hunt 《Journal of agricultural and food chemistry》1999,47(7):2553-2562
Biosynthesis of straight-chain ester volatiles by Granny Smith and Red Delicious apples was investigated using deuterium-labeled fatty acids, C-6 aldehydes, and alcohols. Perdeuterated saturated and monounsaturated fatty acids were metabolized to hexyl-d(11), hexanoate-d(11), heptanoate-d(13), and octanoate-d(15) esters, whereas perdeuterated linoleic acid produced only hexyl-d(11) and hexanoate-d(11) esters. Exposure of fruit to vapors of deuterated 3Z-hexenal, 2E-hexenal, and hexanal identified the following biosynthetic processes: (1) isomerization between 3E, 3Z, and 2E-hexenals; (2) reduction to 3E, 3Z, and 2E-hexenyl esters; (3) reduction to hexanol and hexyl esters; (4) oxidation to hexanoic acid and formation of hexanoate esters; (5) beta-oxidation of hexanoic acid leading to butyl and butanoate esters; and (6) alpha-oxidation of hexanoic acid leading to pentyl and pentanoate esters. Unsaturated straight-chain ester volatiles appear to arise only by the lipoxygenase pathway and may be useful indicators of lipoxygenase activity in fruit. 相似文献
13.
Characteristic aroma components of water dropwort (Oenanthe javanica DC.) were evaluated by aroma extract dilution analysis and solid-phase microextraction-gas chromatography-olfactometry. Alpha-Terpinolene (plastic/cucumber-like) was the most intense aroma-active compound in water dropwort. Other potent aroma-active compounds included p-cymene (kerosene-like), alpha-terpinene (lemon), (E)-caryophyllene (woody), (Z,E)-alpha-farnesene (woody), hexanal (green), (Z)-3-hexenol (green), phenylacetaldehyde (honey), (E)-2-nonenal (cucumber), bornyl acetate (cooked vegetable), and gamma-terpinene (lemon). Of these, p-cymene was believed to be primarily responsible for the distinct kerosene-like aroma note of water dropwort. The aroma property of p-cymene was dependent on its concentration and was described as kerosene-like at relatively high concentrations but changed to citrus and green aroma notes at low concentrations. 相似文献
14.
The dynamic headspace procedure of aroma extraction was optimized on Gala apples (Malus domestica). Two parameters affecting the extractability of compounds were studied: temperature and purge time. The influence of artificial saliva was also included. An increase in purge time and temperature caused an increase in the extraction of volatiles from the apple matrix. The optimum point of extraction was 40 degrees C and 70 min of purge. The study also showed that the addition of saliva influenced the extraction of volatile compounds, but this effect was different from one compound to another. To verify that the headspace extracts presented a global odor representativeness of fresh apple under these conditions of extraction, eight assessors compared the odor of extracts with fresh fruit odor for three different cultivars. With regard to the sensory profiles of extracts, the optimal conditions of extraction were suitable for extraction of volatile compounds, even if cooked apple odor appeared in some extracts. The similarity marks of extracts were low but acceptable. 相似文献
15.
苹果采摘机器人视觉系统研究进展 总被引：14，自引：10，他引：4
视觉系统是苹果采摘机器人最重要的组成部分之一,它在一定程度上决定了苹果采摘机器人完成采摘任务的质量及速度。为明确苹果采摘机器人视觉系统所面临的挑战及未来研究方向,该文首先对世界各国现有苹果采摘机器人的研究情况从视觉传感器类型、视觉系统硬件组成、采摘成功率及作业时间等方面进行了概述,然后分别对现有苹果采摘机器人视觉系统中苹果图像分割方法、受着色度、光照、表面阴影、振荡、重叠及遮挡等影响下的苹果目标的识别与定位方法、苹果采摘机器人视觉系统对枝干等障碍物的识别方法以及视觉系统中双目视觉技术立体匹配问题进行了综述,进一步分析了苹果采摘机器人视觉系统中存在的问题,指出视觉系统结构的优化、视觉系统中智能算法的优化、提高视觉系统的实时性、振荡苹果目标的识别与定位、视觉系统受振动影响时苹果目标的识别与定位及提高视觉系统的性价比等方面将成为未来重点研究方向,为深入研究苹果采摘机器人视觉系统提供参考。 相似文献
16.
Kavvadias D Beuerle T Wein M Boss B König T Schwab W 《Journal of agricultural and food chemistry》1999,47(12):5178-5183
Extracts obtained by XAD solid-phase extraction of apple juice and cider were separated by liquid chromatography on silica gel. Several new 1,3-dioxanes including the known 2-methyl-4-pentyl-1,3-dioxane and 2-methyl-4-[2'(Z)-pentenyl]-1,3-dioxane, were identified in the nonpolar fractions by GC/MS analysis and confirmed by chemical synthesis. The enantioselective synthesis of the stereoisomers of the 1,3-dioxanes was performed using (R)- and (R,S)-octane-1,3-diol and (R)- and (R,S)-5(Z)-octene-1,3-diol as starting material. Comparison with the isolated products indicated that the natural products consisted of a mixture of (2S,4R) and (2R,4R) stereoisomers in the ratio of approximately 10:1, except for 1,3-dioxanes generated from acetone and 2-butanone. It is assumed that the 1, 3-dioxanes are chemically formed in the apples and cider from the natural apple ingredients (R)-octane-1,3-diol, (R)-5(Z)-octene-1, 3-diol, (3R,7R)- and (3R,7S)-octane-1,3,7-triol, and the appropriate aldehydes and ketones, which are produced either by the apples or by yeast during fermentation of the apple juice. 相似文献
17.
Polyphenolic compounds of apple may play an important role in physiologic functions related to human health. Different polyphenolics may have varied biological activities including antioxidant activity. The objective of this study was to investigate the profiles of polyphenolic compounds in different apple varieties and different parts of an apple. The total and individual polyphenolics differed significantly among the eight apple cultivars grown in Ontario, and the peels had higher concentrations than the flesh. Among the tested cultivars, Red Delicious and Northern Spy had the highest concentrations and Empire the lowest. Five major polyphenolic groups with a total of 16 identified individual compounds were found, among which the dihydroxycinnamic acid esters, phloretin glycosides, and flavan-3-ols were found in both flesh and peel, whereas quercetin glycosides were almost exclusively found in the peel. Cyanidin 3-galactoside was unique to and found only in red apple peels. In both apple peel and flesh, the predominant group of polyphenolics was the procyanidins, followed by quercetin glycosides in the peel and hydroxycinnamic acid esters in the flesh. 3-Hydroxyphloretin 2'-xyloglucoside was newly identified in apple. The results obtained in this study will further the understanding of the polyphenolic composition of apples and their roles in health-promoting physiological functions. 相似文献
18.
The volatiles produced by leaves and fruits of Olea europaea cv. Olivastra Seggianese have been analyzed in two different phenological stages. Furthermore, the volatiles of the virgin olive oil obtained from ripe fruits has been characterized. The volatiles were sampled by means of two different techniques: hydrodistillation and SPME. Differences were observed between the two different collection times, the different organs, and sampling techniques. The major constituents were often aldehydes, particularly (E)-2-hexenal (9.8-48.0%); however, also many terpenoids have been identified, mainly (E,E)-alpha-farnesene (0.2-27.0%), linalool (0-3.6%), beta-caryophyllene (0-8.1%), and valencene (0-2.5%). This is the first investigation on this cultivar. 相似文献
19.
Activity and concentration of polyphenolic antioxidants in apple: effect of cultivar, harvest year, and storage conditions 总被引：4，自引：0，他引：4
van der Sluis AA Dekker M de Jager A Jongen WM 《Journal of agricultural and food chemistry》2001,49(8):3606-3613
Consumers' increasing interest in the relationship between diet and health is a sign for food producers to pay more attention to potential health-protecting compounds in new product development and food processing. From a production chain perspective the choice of the raw material that is used is important for the health-protecting potential of the end product. Four apple cultivars (Jonagold, Golden Delicious, Cox's Orange, and Elstar), which can be used as fresh apples or in processed apple products, were compared with regard to flavonol, catechins, phloridzin, and chlorogenic acid concentrations and antioxidant activity. Jonagold apples possessed the highest flavonoid concentration and the highest antioxidant activity. To study seasonal differences, apples from three different harvest years were analyzed, but in three cultivars no effect on flavonoid concentration and antioxidant activity was observed. Long-term storage, both at refrigerator temperature and under controlled atmosphere conditions, was found not to influence flavonoid concentration or antioxidant activity. 相似文献
20.
To understand the role of ethylene in regulating the overall flavor of apple fruits, ethylene production or action was reduced using transgenic apple trees suppressed for ACC-synthase or ACC-oxidase enzyme activity or by the addition of 1-methylcyclopropene (1-MCP), an ethylene action inhibitor. Flavor components were differentially regulated in response to the suppression of both ethylene biosynthesis and action. Headspace analysis of aroma production, an ethylene-associated event, showed a reduction in ester and alcohol production in the ethylene-suppressed lines and in the apples treated with 1 microL L(-1) 1-MCP for 20 h at 20 degrees C. However, no major differences were observed in the concentrations of aldehyde volatiles. Other flavor metabolites that showed an ethylene-dependent pattern were organic acids and sugars. Malic acid degradation was significantly reduced under ethylene-suppressed conditions, showing a recovery after the fruit was exposed to ethylene. Sucrose and fructose concentrations were influenced by suppression or enhancement of ethylene. Total phenolics as well as individual phenolic compounds showed an ethylene-dependent regulation only in response to the suppression of ethylene biosynthesis, but not when ethylene action was inhibited. 相似文献