W-默科特单性结实能力与果实不同部位四种内源激素含量的关系

为了探讨植物内源激素对单性结实的影响,本研究选取兼性单性结实能力较强的柑橘品种‘w-默科特’为试材,对其进行授粉和不授粉处理,观测胚珠和果实发育以及生理落果过程,同步以HPLC法测定不同处理的果实各部位内源激素的含量。结果表明,32~39DAF(花后天数)是W-默科特胚珠发育的关键时期,胚珠形态出现明显的差异。25-50DAF正好与柑橘生理落果主要发生期对应,胚珠中ABA含量最高,且未授粉W-默科特显著高于授粉W-默科特,败育胚珠可能是果实中ABA的主要来源部位;同期的促生长类激素,胚珠中ZT含量与果肉比较接近,低于果皮,但GA3、IAA含量明显低于果肉,未授粉W-默科特和授粉W-默科特则高低互现,总体差异较小。均值处理后的激素比值T综合展示了两类激素间的变化关系,在25?50DAF,未授粉W-默科特整果的T值较授粉W-默科特整果更高,这可能是果肉或果皮产生了更高的生长类激素,克服了败育胚珠产生的较高ABA,减少了生理落果,保障了W-默科特单性结实。本研究结果为进一步研究柑橘单性结实和前期生理落果提供了数据参考。     

柑橘皮膳食纤维在曲奇饼干中的应用研究

以汉中当地宫川柑橘为试材,从柑橘皮中提取水不溶性膳食纤维,用于曲奇饼干的制作。通过单因素试验和正交试验,对曲奇饼干的原料配方参数进行筛选。结果表明,柑橘皮膳食纤维曲奇饼干的最佳配方为:以低筋面粉质量100%计,牛奶添加量10%,蛋液添加量20%,黄油添加量40%,细砂糖添加量25%,膳食纤维添加量6%,所制得的柑橘皮膳食纤维曲奇饼干外观完整,表面呈棕黄色,口感酥脆、细腻,有奶香味,无杂质。     

柑橙橘柚类水果采后处理和贮藏风险控制(下)

根据柑橙橘柚类水果的生物学特性,论述了专业贮藏该类水果的冷库在温度、湿度和通风调控、杀菌等方面的特殊要求,指出了果实采前病害防治的重要性、适宜采收成熟度的判定方法以及果品采后常用保鲜杀菌药剂的使用方法,提出贮藏冷库管理、果品品质预测分析和及时处理要点,以最大限度地防范与降低该类果品的贮藏风险。     

柑橙橘柚类水果采后处理和贮藏风险控制(上)

根据柑橙橘柚类水果的生物学特性．论述了该类果实采后贮藏保鲜的工艺条件以及主要采后生理病害与侵染性病害的发生规律与防治措施。     

Does ethylene degreening affect internal quality of citrus fruit?

Citrus fruit are non-climacteric. However, exposure to exogenous ethylene, e.g., during ethylene degreening, stimulates various ripening-related processes in the peel tissue, such as destruction of the green chlorophyll pigments and accumulation of orange/yellow carotenoids. Nonetheless, it is not yet known whether exogenous ethylene affects internal ripening processes in citrus flesh. To address this question, we examined the possible effects of ethylene on taste, aroma, perceived flavor, and nutritional quality of various citrus fruit, including ‘Navel’ oranges, ‘Star Ruby’ grapefruit and ‘Satsuma’ mandarins. Exposure to ethylene enhanced peel color break, and respiration and ethylene production rates in all citrus fruit tested. However, ethylene degreening had no effect on juice total soluble solids and acid contents, and had only minor effects on contents and composition of juice aroma volatiles. Moreover, sensory analysis tests revealed that ethylene degreening did not affect the flavor of oranges and grapefruit, but marginally impaired sensory acceptability of mandarins; the latter change could be attributed, at least partially, to storage of the fruit for 5 days at 20 °C. Nevertheless, ethylene degreening did not enhance off-flavor perception or accumulation of off-flavor volatiles, nor had any effect on levels of health promoting compounds such as vitamin C, total phenols and flavonoids, or antioxidant-activity of citrus juice. We conclude that although ethylene affects peel color break, it is probably not involved in regulation of internal ripening processes in citrus fruit and, therefore, does not impair internal fruit quality.     

柑橘皮膳食纤维面包的开发及其体外消化特性的研究

柑橘皮渣是柑橘加工中的副产物,含有大量膳食纤维。将柑橘皮渣膳食纤维应用到面包的生产中,通过质构和感官分析,采用单因素及正交试验优化了膳食纤维面包的配方,并对其体外消化特性进行了研究。结果表明,膳食纤维面包的最佳配方为:面粉200 g,牛奶140 g,盐2 g,面包改良剂1 g,膳食纤维6 g,黄油20 g,酵母4 g,白砂糖20 g。此条件下,膳食纤维面包的含水量、酸度和比容均符合GB/T 20981—2007。体外消化试验结果表明:20 min内,膳食纤维面包中淀粉的消化速率显著低于对照,消化产生的还原糖相当于对照的72.86%~77.83%;但是添加膳食纤维不会影响面包中淀粉的总体可利用率。     

橘皮中黄色素提取工艺研究进展

橘皮中主要含有天然色素、果胶、黄酮等多种有效成分,它具有一定的营养价值和保健价值。为了综合利用柑橘皮渣、提高其经济价值、减少环境污染、积极发挥其在食品工业领域重要作用,对超声波辅助提取法、溶剂浸提法、高压法、索氏提取法、微波辅助萃取法等不同提取方法对黄色素的提取进行简要综述,从而提供一定的理论基础和依据为橘皮黄色素的深入研究开发。     

Phospholipase A2 and postharvest peel pitting in citrus fruit

The role of phospholipase A₂ (PLA₂) activity in development of postharvest peel pitting in mature ‘Fallglo’ tangerines [Bower citrus hybrid (Citrus reticulata Blanco × C. reticulata Blanco × C. paradisi Macf.) × Temple (C. reticulata Blanco × Citrus sinensis L.)] and ‘Navel’ oranges (Citrus sinensis L. Osbeck) was investigated. Changes in RH from 30% to 90% followed by fruit waxing increased electrolyte leakage and PLA₂ activity in flavedo, and induced pitting. Treatment with an aqueous dip of aristolochic acid (AT), a specific inhibitor of secretory phospholipase A₂ (sPLA₂) activity, immediately before transfer from 30% to 90% RH storage, markedly reduced peel pitting symptoms. Five genes encoding various phospholipase As isolated from citrus (three patatin-like and two sPLA₂-like sequences) differentially accumulated in healthy areas, areas with developing lesions and necrotic lesions of disordered fruit. Other PLA₂, phospholipase C, and phospholipase D inhibitors also reduced peel pitting; however, PLA₂ inhibitors were the most effective in preventing the disorder. In addition, phospholipase inhibitors promoted fruit decay, suggesting that innate resistance is impacted by phospholipase action. Together, the results provide evidence for involvement of phospholipase activity in development of postharvest peel pitting symptoms in citrus fruit.     

EXTRACTION OF HESPERIDIN FROM FRESH CITRUS PEEL

This paper introduces the method of extracting hespredin from fresh citrus peel, and states the extracting conditions in detail. Hesperidin is an improtant medical material. The firstrate hesperidin can be obtainted by using this method.     

Correlation and path-coefficient analyses of ripening attributes and storage disorders in ‘Ambrosia’ and ‘Empire’ apples

The objectives of this study were: (1) to determine correlation effects among the ripening attributes of ‘Empire’ and ‘Ambrosia’ apples during storage, and (2) to determine the direct and indirect contributions of these ripening attributes on the incidence of physiological disorders and storage rots using path-coefficient analysis. The analysis was applied to data obtained from a variety of harvest dates and storage regimes from apples. Pearson correlation analysis of the data indicated a strong positive correlation between internal ethylene concentration (IEC) and peel greasiness, a negative correlation between IEC and soluble solids concentration, and a negative correlation between firmness and peel greasiness in both cultivars, as well as a negative correlation between IEC and firmness in ‘Empire’. Results indicated that increased IEC in ‘Ambrosia’ apples during storage was related to higher incidences of core browning and lenticel damage and lower incidence of internal browning. Higher IEC in ‘Empire’ apples during storage was associated with less internal browning. Several significant correlations, representing different relationships among the ripening attributes and storage disorders were obtained.     

柚皮的研究进展

柚皮中含有丰富的活性物质,具有较高的保健和药用价值。对柚皮进行深加工综合利用,既可以保护环境,也可以带动农村经济发展。综述了柚皮的生理功效,介绍了近年来关于柚皮的加工利用现状,提出了存在的问题,并讨论了柚皮的未来发展趋势。     

柑橘采后生理及病害研究进展

柑橘采后仍是活的有机体,由于切断了树体的营养供给,其果实品质和生理代谢等发生了重大变化。本文综述柑橘采后生理代谢(水分、营养、呼吸作用和酶活性等)的变化、生理病害(枯水病、褐斑病、冷害等)及病害防治技术(控制温度、热处理、保鲜剂处理、气调贮藏、涂膜处理、臭氧处理等)的研究进展,并指出进一步的研究方向。     

柑橘贮藏保鲜研究进展

综述了柑橘贮藏保鲜的研究现状和发展趋势,介绍了柑橘采后生理代谢、防腐保鲜技术、贮藏设施和条件、采后分子机理的研究。     

Effect of postharvest ethylene treatment on carotenoid accumulation and the expression of carotenoid biosynthetic genes in the flavedo of orange (Citrus sinensis L. Osbeck) fruit

Degreening with ethylene is a common postharvest practice in citrus fruit. In this work we have examined the effect of ethylene treatment on carotenoid content and composition, and on the expression of carotenoid biosynthetic genes in the flavedo of Navelate orange (Citrus sinensis L.) harvested at two ripening stages. The ethylene-induced fruit coloration and carotenoid content in the flavedo increased with the ripening stage of the fruit. Analysis of the changes in individual carotenoids revealed that ethylene stimulated an increase in phytoene, phytofluene, (9Z)-violaxanthin which is the main carotenoid in fully ripened orange peel, and the apocarotenoid β-citraurin, and decreased the concentration of chloroplastic carotenoids. These changes are consistent with the effect of ethylene on the expression of carotenoid biosynthetic genes, since it up-regulated the expression of phytoene synthase, ζ-carotene desaturase and β-carotene hydroxylase genes, sustained or transiently increased accumulation of phytoene desaturase, plastid terminal oxidase, β-lycopene cyclase and zeaxanthin epoxidase mRNAs, and decreased the expression of the ɛ-lycopene cyclase gene. These data indicate that exogenous ethylene reproduces and accelerates the physiological and molecular changes in the carotenoid biosynthesis naturally occurring during maturation of citrus fruit. On the other hand, gibberellic acid, which delays fruit degreening, reduced the ethylene-induced expression of early carotenoid biosynthetic genes and the accumulation of phytoene, phytofluene and β-citraurin.     

橘皮果胶提取条件的研究

以韶关产槿柑为试材,采用正交设计试验方法,研究了温度、水料比、pH和提取时间四因素对橘皮果胶提取的影响。结果表明,影响橘皮果胶提取的因素由强到弱依次为：pH〉温度〉提取时间〉水料比;果胶提取的最佳条件为：温度85oC,水料比15：1,pH值1．5,提取时间90min。在此基础上,还探讨了蒸馏提取橘皮精油后联产果胶的工艺。     

Spectral reflectance characteristics of citrus canker and other peel conditions of grapefruit

The presence of one fruit infected with citrus canker in a shipment may render the whole shipment unmarketable. Therefore it is important to classify fruit infected with citrus canker in the packinghouse before shipping the produce. The purpose of this research was to determine the significant wavelengths that could be used to classify canker among other peel conditions using grapefruit, a variety susceptible to canker. A spectrophotometer, with a wavelength range of 200–2500 nm, was used to measure the spectral reflectance data of peels from market quality fruit and fruits that were infected with cake melanose, wind scar, copper burn, greasy spot and canker. Statistical data analysis was performed on the spectral reflectance data to identify the wavelengths that had maximum discriminatory potential among the different peel conditions and to derive a discriminant function from the identified wavelengths. The discriminatory wavelengths were identified in the visible and the visible near infrared range. In addition, the classification based on the derived discriminant function resulted in 100% classification of canker. These results provide fundamental and practical use in the development of an automatic fruit sorter for canker classification based on spectral reflectance. Future research would involve the development of a vision-based classification system using the significant wavelengths identified in this study.     

柚皮精油的溶剂提取与GC-MS分析

利用微波辅助-有机溶剂法提取柚皮精油,并利用GC-MS对其进行了有效成分鉴定。结果表明,在石油醚、正己烷和环己烷3种非极性溶剂中,采用石油醚作溶剂提取效率最高,精油得率为1.25%;应用GC-MS检测鉴定出柚皮精油中19种化合物,占总组分的60.58%。     

防治草莓连作障碍的复合生防制剂的筛选

为有效解决单一使用解酚菌或药用植物材料防治草莓连作障碍过程靶标单一的问题,拟将二者有效结合制成复合生防制剂,达到祛毒抑菌的作用。本试验选用解酚菌B3512与6种对草莓枯萎病有抑制作用的药用植物（姜黄、青皮、山柰、枳实、Z1、Z2）为试材,测定B3512在6种药用植物材料上的生长速率。结合抑菌试验,确定以姜黄为基质,玉米秸秆粉、麦麸为碳源、氮源时,B3512的生长速率最快且对草莓枯萎病病原菌的抑菌率最高;同时筛选出以姜黄为基质利于B3512定植,增殖的固体发酵培养基配方及条件,配方为麦麸:玉米秸秆粉:姜黄按20:10:6的比例混合,B3512以20%的接种量、最适温度32℃、初始含水量50%、初始pH 7.0、培养96 h时,B3512的繁殖能力最强且活菌数最高。     

福桔果皮精油对黄粉虫成虫的驱避作用和种群抑制作用

用水蒸汽蒸馏法提取福桔果皮精油后采用气相色谱质谱联用法分析出其主要成分是α-柠檬烯。采用滤纸药膜法和饲料拌药法分别研究了福桔果皮精油对黄粉虫成虫的驱避作用和种群抑制作用,研究结果表明：桔果皮精油对黄粉虫成虫有明显的驱避作用和种群抑制作用,驱避作用和种群抑制作用随着剂量的增加而加强。