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1.
This study was conducted to determine the lipolytic effects of eight kinds of citrus peel oils and their components. All of the citrus peel oils revealed lipolytic effects on olive oil model solution ranging from 10.9 to 73.8%. Hakyul (Citrus natsudaidai Hayata) showed the highest lipolytic effect (73.8%), followed by yuza (Citrus junos Sieb. ex Tanaka, 68.1%) and lemon (Citrus limonium, 63.4%), and their effects were comparable with or stronger than that of 5 mM raspberry ketone (p < 0.05). Among 17 authentic compounds relating to citrus peel oils, octanal (78.6%) showed the highest lipolytic effect, followed by gamma-terpinene (76.3%), limonene (75%), terpinen-4-ol (70.7%), nerol (69.9%), p-cymene (67.7%), and geranyl acetate (67.2%), and their effects were stronger than that of 5 mM raspberry ketone (p < 0.05). Ethyl acetate, alpha-pinene, myrcene, citronellal, linallyl acetate, and citronellol exhibited poor lipolytic effect in the model solution. Lipolytic effect was found to be high when the oils included a higher content of gamma-terpinene and p-cymene. Limonene showed potential lipolytic effect, and its effect is likely to be enhanced by the presence of gamma-terpinene and p-cymene. It is considered that monoterpene hydrocarbons consisting of one or two double bonds would have stronger lipolytic effect than those having three double bonds.  相似文献   

2.
The volatile components of Hyuganatsu (Citrus tamurana Hort. ex Tanaka) peel oil, isolated by cold-pressing, were investigated by chemical and sensory analyses. According to chemical analysis by GC and GC-MS, limonene (84.0%) was the most abundant compound, followed by gamma-terpinene (6.9%), myrcene (2.2%), alpha-pinene (1.2%), and linalool (1.0%). Monoterpene hydrocarbons were predominant in Hyuganatsu peel oil. The odor-active volatiles in Hyuganatsu flavor were studied by GC-olfactometry and omission tests. The characteristic flavor was present in the oxygenated fraction. Flavor dilution (FD) factors of the volatile flavor components of the Hyuganatsu cold-pressed oil were determined by aroma extraction dilution analysis (AEDA). Furthermore, relative flavor activity was investigated by means of FD factor and weight percent. Ten kinds of odor compounds having Hyuganatsu-like aroma were detected by AEDA: limonene, linalool, octanol, neral, neryl acetate, tridecanal, trans-carveol, cis-nerolidol, trans,trans-farnesyl acetate, and trans,trans-farnesol. Linalool and octanol were regarded as the most odor-active or key compounds of Hyuganatsu aroma. Diluted solutions of linalool and octanol of approximately 2 ppm gave a fresh and fruity aroma note similar to Hyuganatsu flavor.  相似文献   

3.
Twenty-eight kinds of citrus essential oils and their components were studied for inhibitory effects on the formation of N-nitrosodimethylamine (NDMA). The reaction mixture consisted of dimethylamine and sodium nitrite adjusted at pH 3.6, in addition to essential oils and an emulsifying agent. The quantification was determined by high-performance liquid chromatography monitored at 220 nm. All of the essential oils inhibited the formation of NDMA in the range of 20-85%. The oils of ujukitsu (Citrus ujukitsu Hort. ex Shirai), yuzu (C. junos Tanaka), mochiyu (C. inflata Hort. ex Tanaka), and ponkan (C. reticulata Blanco cv. F-2426) inhibited the formation of NDMA much more effectively than other citrus oils. The inhibitory proportions of components of citrus essential oils such as myrcene, alpha-terpinene, and terpinolene were as high as 80%.  相似文献   

4.
Thirty-four kinds of citrus essential oils and their components were investigated for radical-scavenging activities by the HPLC method using 1,1-diphenyl-2-picrylhydrazyl (DPPH). To examine the oils' relative radical-scavenging activities compared with that of a standard antioxidant, Trolox was employed. All of the essential oils were found to have scavenging effects on DPPH in the range of 17. 7-64.0%. The radical-scavenging activities of 31 kinds of citrus essential oils were comparable with or stronger than that of Trolox (p < 0.05). The oils of Ichang lemon (64.0%, 172.2 mg of Trolox equiv/mL), Tahiti lime (63.2%, 170.2 mg of Trolox equiv/mL), and Eureka lemon (61.8%, 166.2 mg of Trolox equiv/mL) were stronger radical scavengers than other citrus oils. Citrus volatile components such as geraniol (87.7%, 235.9 mg of Trolox equiv/mL), terpinolene (87.4%, 235.2 mg of Trolox equiv/mL), and gamma-terpinene (84.7%, 227.9 mg of Trolox equiv/mL) showed marked scavenging activities on DPPH (p < 0.05).  相似文献   

5.
Ginger oil, obtained by steam distillation of the rhizome of Zingiber officinale Roscoe, is used in the beverage and fragrance industries. Ginger oil displays considerable compositional diversity, but is typically characterized by a high content of sesquiterpene hydrocarbons, including zingiberene, ar-curcumene, beta-bisabolene, and beta-sesquiphellandrene. Australian ginger oil has a reputation for possessing a particular "lemony" aroma, due to its high content of the isomers neral and geranial, often collectively referred to as citral. Fresh rhizomes of 17 clones of Australian ginger, including commercial cultivars and experimental tetraploid clones, were steam distilled 7 weeks post-harvest, and the resulting oils were analyzed by GC-MS. The essential oils of 16 of the 17 clones, including the tetraploid clones and their parent cultivar, were found to be of substantially similar composition. These oils were characterized by very high citral levels (51-71%) and relatively low levels of the sesquiterpene hydrocarbons typical of ginger oil. The citral levels of most of these oils exceeded those previously reported for ginger oils. The neral-to-geranial ratio was shown to be remarkably constant (0.61 +/- 0.01) across all 17 clones. One clone, the cultivar "Jamaican", yielded oil with a substantially different composition, lower citral content and higher levels of sesquiterpene hydrocarbons. Because this cultivar also contains significantly higher concentrations of pungent gingerols, it possesses unique aroma and flavor characteristics, which should be of commercial interest.  相似文献   

6.
The qualitative and quantitative composition of the essential oil from black, green, and white pepper was determined by using a simultaneous distillation and extraction micromethod for oil isolation and gas chromatography (GC)/flame ionization detection (FID) and GC/mass spectrometry (MS) analysis techniques. The most abundant compounds in pepper oils were (E)-beta-caryophyllene (1.4-70.4%), limonene (2.9-38.4%), beta-pinene (0.7-25.6%), Delta-3-carene (1.7-19.0%), sabinene (0-12.2%), alpha-pinene (0.3-10.4%), eugenol (0.1-41.0%), terpinen-4-ol (0-13.2%), hedycaryol (0-9.1%), beta-eudesmol (0-9.7%), and caryophyllene oxide (0.1-7.2%). Green pepper corn obtained by a sublimation drying method gave more oil (12.1 mg/g) and a much higher content of monoterpenes (84.2%) in the oil than air-dried green pepper corn (0.8 mg/g and 26.8%, respectively). The oil from ground black pepper contained more monoterpenes and less sesquiterprnes and oxygenated terpenoids as compared to green and white pepper oils. After 1 year of storage of pepper samples in a glass vessel at room temperature, the amount of the oils isolated decreased, the content of terpenes decreased, and the amount of oxygenated terpenoids increased. Differently from other pepper samples, 1 year storage of green pepper corn raised the oil amount more than twice of both drying methods.  相似文献   

7.
Tacle and Clara [Monreal clementine (Citrus clementina Hort. ex Tan) x Tarocco orange (Citrus sinensis L. Osbeck)] are two new triploid citrus hybrids developed by the CRA-Istituto Sperimentale per l'Agrumicoltura (Acireale, Italy). The fruits are easy-peeling and juicy, have a pleasant taste like the Tarocco orange, and are sweet like the Monreal clementine. In addition, a distinctively attractive characteristic of these mandarin-like fruits is the red-pigmented flesh caused by the presence of anthocyanins. This study reports the juice quality attributes of fresh fruits harvested at different ripening stages and of cold-stored fruits kept for 104 days at 6+/-1 degrees C and 90-95% relative humidity. Physico-chemical analyses showed that the fresh-fruit juice yield ranged between 39 (Tacle) and 41% (Clara); these values were 11-14% lower after 104 days of storage. Vitamin C content in the Clara juice was decisively higher than that in the Tacle juice. Juice anthocyanins and other polyphenols increased during cold storage. These results show that low-temperature storage enhances the functional attributes of Tacle and Clara fruit juices.  相似文献   

8.
为了解决普通检测装置难以覆盖不同果径（25～95mm）柑橘的检测需求问题,研发了覆盖多果径柑橘的便携式双档位多品质无损检测装置。以砂糖橘（果径25.35～48.61mm）和武鸣沃柑（果径53.24～94.71mm）为研究对象,基于研发的双档位探头,在赤道部位每隔120°采集一次光谱,平均光谱作为该柑橘的原始光谱。经标准正态变量变换（standard normal variable,SNV）、多元散射校正（multiplicative scatter correction,MSC）预处理,再利用竞争性自适应加权抽样算法（competitive adaptive reweighted sampling, CARS）筛选特征波长,分别建立了沃柑和砂糖橘的可溶性固形物含量（soluble solids content,SSC）和水分的偏最小二乘预测模型。沃柑的SSC和水分预测模型验证集相关系数分别为0.937、0.951,均方根误差分别为0.382°Brix、0.491%;砂糖橘的SSC和水分预测模型验证集相关系数分别为0.921、0.935,均方根误差分别为0.460°Brix、0.673%...  相似文献   

9.
磷、钾营养对柑桔果实产量、品质和贮藏性的影响   总被引：15，自引：3，他引：15  
采用田间试验以柑为材料研究了连续4年施用磷、钾肥后对柑桔果实的产量、品质和贮藏性的影响。结果表明,施用磷、钾肥,尤其磷、钾肥配施可显著提高柑桔果实的单果重和产量,以及采收时果实的可溶性固形物含量、可溶性糖含量、还原糖含量、糖/酸比和维生素C(Vc)含量,降低可滴定酸含量;并且可以有效地降低柑桔果实在贮藏过程中的失重率和烂果率,减缓糖分、酸度和Vc含量的下降。磷钾营养对于提高柑桔果实的耐贮性和维持贮藏过程中果实的风味和营养品质有一定的作用。  相似文献   

10.
Crushing intensity and distillation time were evaluated for their effects on the oil yield and composition of steam-distilled essential oil from fruits of Coriandrum sativum var. microcarpum L. A comparison of oils produced by laboratory- and pilot-scale stills showed that the two still types gave comparable yields and oil composition. The laboratory still was then used to compare oil yields and compositions from fruits crushed at three different intensities, at intervals during a distillation period of 60 min. Both crushing intensity and distillation time had significant (P< 0.05) effects on the yield and composition of the oil. The maximum oil yield was less from the light-crushed fruits, but the rate of oil recovery was significantly P < 0.05) higher. From the light-crushed fruits, 95% of the maximum yield was extracted in 22.5 min compared with 32 and 39 min for the standard and heavy-crushed fruits, respectively. The effect of crushing intensity on oil composition was most pronounced on the low-boiling-point a-pinene and on the higher-boiling-point geranyl acetate. Crushing had little effect on linalool content, but distillation time could be manipulated to alter the linalool content of the oil.  相似文献   

11.
The chemical composition of the essential oils obtained from the leaves, the barks of the stem and the root, as well as from the fresh and dried fruits of Xylopia aethiopica, growing in Ghana, was investigated by gas chromatography/mass spectrometry analyses. Kovats indices, mass spectra, and standard compounds were used to identify a total of 93 individual compounds. The monoterpene hydrocarbons formed the main portion in all studied samples. beta-Pinene was predominant in all cases, while trans-m-mentha-1(7),8-diene was the main compound in the essential oils of the leaves and the barks of roots and stems. Their potential antioxidant activity was also investigated and found to be significant in scavenging superoxide anion radical.  相似文献   

12.
In this study, the contamination by chloroparaffin of Sicilian and Calabrian citrus essential oils, produced in the crop years 1994-1996, was investigated. The analyses were carried out on 102 lemon oils, 98 orange oils, and 96 mandarin oils, using a dual-channel GC-ECD. It was found that 53% of lemon oil, 33% of orange oil, and 38% of mandarin oil samples were contaminated. The mean contamination levels were 7.1 ppm (lemon), 2.5 ppm (orange), and 5.3 ppm (mandarin). The highest concentration of chloroparaffin found was 60 ppm in a lemon oil sample.  相似文献   

13.
More than 50 compounds were identified in essential oils from stems and leaves of Salvia officinalis L. plants harvested in July, in Arouca, in northern Portugal. About 40 of those compounds were also present in flower essential oils, collected from the same plants. alpha-Thujone was the major compound, representing about 55, 30, and 18% of the essential oils from stems, leaves, and flowers, respectively. Significant percentage variations in the main compound classes of the essential oils from shoots sampled over the year were recorded at two different sites in northern Portugal. From December to April, oxygenated monoterpenes (MO) decreased from approximately 67-72% to values of 42-43% of the essential oils. During the same time interval, the percentage of monoterpene hydrocarbons (MH) rose from 8-11% to 17-22%. At both sites, sesquiterpene hydrocarbons (SH) rose from approximately 7% in February to 19-22% in April, decreasing thereafter to approximately 9% in July. Oxygenated sesquiterpenes (SO) increased from a minimum of approximately 5% in July to a maximum of 8-11% in February, decreasing thereafter. The compounds that mostly accounted for the essential oil composition variation were alpha-pinene, beta-pinene, and camphene, as MH; alpha-thujone and camphor, as MO; alpha-humulene and beta-caryophyllene, as SH; and viridiflorol, as SO.  相似文献   

14.
红壤丘陵区坡地土壤颗粒组成的空间分布特征研究   总被引：4，自引：0，他引：4  
王冬冬  高磊  陈效民  彭新华 《土壤》2016,48(2):361-367
通过分析红壤丘陵区农田坡面14个0~100 cm剖面的土壤颗粒组成,结合研究区土壤侵蚀等相关资料,拟阐明坡面尺度土壤砂粒、粉粒和黏粒含量的空间分布特征,揭示自然条件下土壤颗粒组成在水平和垂直方向上的分布规律。结果表明:坡面尺度土壤砂粒、粉粒和黏粒均呈现出中等的空间异质性,变异系数分别介于17.6%~23.2%、10.7%~15.8%和13.5%~17.0%。由于粗颗粒的沉积,花生地和橘园地均表现出坡下的砂粒含量显著高于坡上和坡中(P0.05),黏粒含量坡下显著低于其他坡位(P0.05);由于黏粒更容易随入渗过程向深层运动,两种植被类型均表现出土壤砂粒含量随深度增加而降低(P0.05)、黏粒含量随深度增加而增加的趋势(P0.05)。无论在水平方向还是垂直方向上,粉粒含量均无明显变化规律(P0.05)。砂粒含量随坡位和土壤深度的变化程度均大于粉粒和黏粒。植被类型及相应的耕作制度影响土壤颗粒的分布,土壤砂粒在水平方向上的运动在花生地表现得强于橘园地;橘园地土壤黏粒含量在垂直方向上的迁移速率大于花生地,而对粉粒含量的分布规律影响不大。  相似文献   

15.
The fatty acid profiles and triacylglycerol (TAG) compositions of oils from the solid endosperm of different Philippine coconut hybrids and their parentals were determined by using gas chromatography (GC) and high-performance liquid chromatography (HPLC). In general, varietal differences in fatty acid composition were observed. Lauric acid (C12) content was significantly higher in the hybrids PCA 15-8 (50.45%) and PCA 15-9 (50.26%) by about 3.16% points as compared to other hybrids, and higher in Tacunan Green Dwarf (50.50%) among the parentals. Among the fatty acids, lauric acid exhibited the least variation. In general, none of the hybrids had higher fatty acid content than their parentals. The HPLC chromatogram of triacylglycerols (TAG) showed 8 major peaks which differ in carbon number (CN) by two: identified as TAG CN 30, 32, 34, 36, 38, 40, 42, and 44. TAGs CN 30 (4.08%) and CN 34 (19.20%) were found to be significantly higher in PCA 15-9 than in the other hybrids. CN 36 was highest (21.94-23.66%) in all hybrids and parentals. The TAG CNs varied significantly among hybrids and parents, i.e., in CN 30, 32, and 34, which are high in medium chain triacylglycerols (MCTs), and in CN 30 (for parentals only), 40, 42, and 44 (the latter two for parentals only), and none in CN 36. MCTs calculated for two hybrids and their parents ranged from 13.81% to 20.55%.  相似文献   

16.
中草药淀粉壳聚糖复合膜对椪柑的保鲜效果   总被引：1，自引：1，他引：0  
为探讨可食性涂膜保鲜剂取代化学保鲜和套袋保鲜椪柑的可能性,研究了中草药淀粉壳聚糖复合涂膜剂对椪柑果实保鲜效果及衰老生理的影响。结果表明：复合涂膜可以明显降低椪柑贮藏期间病害指数,保持较高的好果率,其效果与化学保鲜无明显差异,但显著高于单一套袋处理,贮藏第90?d时,其好果率和病情指数分别是单一套袋的1.2倍和50.0%;复合涂膜能减少维生素C、可滴定酸的损失。与单一套袋相比,复合涂膜明显提高过氧化氢酶活性,降低过氧化物酶和多酚氧化酶活性,抑制丙二醛积累,在贮藏第90?d时,过氧化氢酶是单一套袋的2.2倍,过氧化物酶、多酚氧化酶和丙二醛含量分别是单一套袋的60.9%、80.7%和76.7%。在贮藏期间除过氧化物酶外,复合涂膜过氧化氢酶、多酚氧化酶和丙二醛含量与化学保鲜相比无明显差异。通过成本核算,处理1?kg椪柑需0.16元。由此可知,中草药淀粉壳聚糖复合涂膜在抗病和防止果实衰老方面已达到化学保鲜效果,并在品质方面明显优于化学保鲜,成本低且安全,可以替代椪柑果实的化学保鲜和套袋。  相似文献   

17.
The Hibiscus genus encompasses more than 300 species, but kenaf (Hibiscus cannabinus L.) and roselle (Hibiscus sabdariffa L.) are the two most economically important species within the genus. Seeds from these two Hibiscus species contain a relatively high amount of oil with two unusual fatty acids: dihydrosterculic and vernolic acids. The fatty acid composition in the oil can directly affect oil quality and its utilization. However, the variability in oil content and fatty acid composition for these two species is unclear. For these two species, 329 available accessions were acquired from the USDA germplasm collection. Their oil content and fatty acid composition were determined by nuclear magnetic resonance (NMR) and gas chromatography (GC), respectively. Using NMR and GC analyses, we found that Hibiscus seeds on average contained 18% oil and seed oil was composed of six major fatty acids (each >1%) and seven minor fatty acids (each <1%). Hibiscus cannabinus seeds contained significantly higher amounts of oil (18.14%), palmitic (20.75%), oleic (28.91%), vernolic acids (VA, 4.16%), and significantly lower amounts of stearic (3.96%), linoleic (39.49%), and dihydrosterculic acids (DHSA, 1.08%) than H. sabdariffa seeds (17.35%, 18.52%, 25.16%, 3.52%, 4.31%, 44.72%, and 1.57%, respectively). For edible oils, a higher oleic/linoleic (O/L) ratio and lower level of DHSA are preferred, and for industrial oils a high level of VA is preferred. Our results indicate that seeds from H. cannabinus may be of higher quality than H. sabdariffa seeds for these reasons. Significant variability in oil content and major fatty acids was also detected within both species. The variability in oil content and fatty acid composition revealed from this study will be useful for exploring seed utilization and developing new cultivars in these Hibiscus species.  相似文献   

18.
Protein changes in the albedo of citrus fruits on postharvesting storage   总被引：1，自引：0，他引：1  
In this work, major protein changes in the albedo of the fruit peel of Murcott tangor (tangerine x sweet orange) during postharvest ageing were studied through 2D PAGE. Protein content in matured on-tree fruits and in fruits stored in nonstressing [99% relative humidity (RH) and 25 degrees C], cold (99% RH and 4 degrees C), and drought (60% RH and 25 degrees C) conditions was initially determined. Protein identification through MS/MS determinations revealed in all samples analyzed the occurrence of manganese superoxide dismutase (Mn SOD), actin, ATP synthase beta subunit (ATPase), citrus salt-stress associated protein (CitSap), ascorbate peroxidase (APX), translationally controlled tumor protein (TCTP), and a cysteine proteinase (CP) of the papain family. The latter protein was identified in two different gel spots, with different molecular mass, suggesting the simultaneous presence of the proteinase precursor and its active form. While Mn SOD, actin, ATPase, and CitSap were unchanged in the assayed conditions, TCTP and APX were downregulated during the postharvest ageing process. Ageing-induced APX repression was also reversed by drought. CP contents in albedo, which were similar in on- and off-tree fruits, were strongly dependent upon cold storage. The active/total CP protein ratio significantly increased after cold exposure. This proteomic survey indicates that major changes in protein content in the albedo of the peel of postharvest stored citrus fruits are apparently related to the activation of programmed cell death (PCD).  相似文献   

19.
Sterols, triterpene alcohols, and hydrocarbons present in the unsaponifiable fraction of some underutilized tropical seed oils have been examined.The seeds include Telfairia occidentalis (TLO), Andenopus breviflorus (ADB), Cucumeropsis edulis (CME), Antiaris africana (ATF), and Monodora tenuifolia (MNT). The oil content of the seeds was high (34.7-68.8%), whereas triacylglycerols comprised the dominant lipid group in the oils (65.4-73.9%). The percentage of unsaponifiables ranged from 1.1 to 7.9%. Ten sterols were identified in the fractions. In the Cucurbitaceae oils (TLO, CME, and ADB), Delta(7)-sterols constituted the dominant sterols. These include 24-ethylcholesta-7,22E,25-trienol (7), 24-ethylcholesta-7,25-dienol (9), 24Z-ethylidenecholes-7-enol (10), and 24-ethylcholesta-7, 24-dienol (11). However Delta(5)-sterols (1-5) occurred at the highest concentration in the other two samples (ATF and MNT). Fifteeen triterpene alcohols were detected in the fractions. Olean-12-enol (16), isomultiflorenol (8), and lupeol (23) were the dominant alcohols in the Cucurbitaceae family, whereas alpha-amyrin (urs-12-enol) (20) was the dominant triterpene alcohol in ATF and MNT. A mixture of C(18)-C(34) n-alkanes, squalene, and some monoterpenes was detected in the hydrocarbon fraction.  相似文献   

20.
The fresh yields, the essential oil content, and the quality of a sage hybrid (Salvia officinalis x Salvia fruticosa, cv. Newe Ya'ar No. 4, Lamiaceae) as affected by development and harvest time were determined. Marked increases in plant height and in the number of nodes developed per plant together with a modest increase in leaf size were accompanied by dramatic increases (more than 20-fold) in the fresh yields throughout a 50-day growth period. No major changes in the essential oil content per fresh weight and its composition were detected throughout the growth period. In contrast, the compositions of the essential oils obtained from stems, as compared to leaves and leaf-primordia, had marked differences. Developmentally controlled changes in the extractives from individual leaf pairs from the same plant were also noted. In upper young leaves, the oxygenated diterpene manool and the sesquiterpene hydrocarbons alpha-humulene and beta-caryophyllene constituted up to 20%, 8%, and 4% of the total extractives, respectively. In older leaves, the abundance of these components steadily dropped to roughly half their levels in young leaves. Conversely, the proportions of the monoterpenes, particularly the ketones camphor and alpha-thujone, steadily increased with leaf position. Minor changes in the levels of other extractives were also recorded. These studies imply independent regulatory patterns for di-, sesqui-, and monoterpenes in this sage hybrid, and suggest possible agrotechnical means to obtain preferred chemical compositions of its essential oil.  相似文献   

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