Characterization of the Key Aroma Compounds of Citrus flaviculpus Hort. ex Tanaka by Aroma Extraction Dilution Analysis

ABSTRACT: The key aroma compounds were identified in Citrus flaviculpus Hort. ex Tanaka (ki-mikan) by using aroma extraction dilution analysis (AEDA) and the sniff test. Ki-mikan peel oil was extracted by cold-pressing. The highest flavor dilution (FD) factor was found for limonene. β-Phellandrene, carvacrol, spathulenol, camphene, elemol, (+)- trans -limonene oxide, and tetradecane showed higher relative flavor activity. Results of the sniff test of the original essential oil and its oxygenated fraction revealed that tetradecane, linalool, and α-terpineol were regarded as the key aroma compounds of ki-mikan peel oil. A diluted solution of linalool and α-terpineol of 3 ppm gave a ki-mikan-like flavor, while a higher concentration near 100 ppm of tetradecane tended to produce a fresh and fruity aroma note similar to ki-mikan flavor.     

基于顶空-气相色谱-离子迁移谱法的酸橙枳实与甜橙枳实挥发性化学成分表征及鉴别研究

目的 对酸橙枳实与甜橙枳实的挥发性化学成分进行表征以甄别酸橙枳实与甜橙枳实,及鉴别两者与混伪品。方法 采用顶空-气相色谱-离子迁移法(HS-GC-IMS)对酸橙枳实、甜橙枳实、枳实混伪品中的挥发性成分进行分析,筛选特征性的挥发性物质,分别建立酸橙枳实、甜橙枳实的特征性GC-IMS指纹图谱,OPLS-DA法用于验证筛选结果的合理性。结果 基于HS-GC-IMS法共检测到174个峰,并对其中133个峰进行了定性分析,其中41个化合物为首次在枳实中鉴定并报道。筛选得到酸橙特征性挥发性化合物共12个,甜橙枳实特征性挥发性化合物共8个,分别绘制酸橙枳实与甜橙枳实特征性GC-IMS指纹图谱,结合OPLS-DA结果可明显区分酸橙枳实与甜橙枳实、酸橙枳实与混伪品、甜橙枳实与混伪品。结论 所建立的HS-GC-IMS特征性指纹图谱能够实现酸橙枳实与甜橙枳实的甄别以及两者与混伪品的鉴别,能够体现酸橙枳实与甜橙枳实的挥发性物质特征。     

Preparation of a polymethoxyflavone-rich fraction (PRF) of Citrus sunki Hort. ex Tanaka and its antiproliferative effects

The peel of Citrus sunki is a rich source of polymethoxyflavones (PMFs). In this study, a PMF-rich fraction (PRF) was obtained from the peels of C. sunki by hot-water extraction and subsequent fractionation with n-hexane. Six PMFs and two demethylated PMFs were isolated by semi-preparative HPLC, and their structures were identified by ¹H NMR and ¹³C NMR. To define the synergistic effects of PRF, the PRF and its eight individual components were assessed for antiproliferative activity using HL-60 cells. The PRF showed greater growth inhibitory activity (IC₅₀ value = 25.14 μg/ml), compared with its individual components. Flow cytometric analysis confirmed that the PRF significantly increased the percentage of sub-G₁ cells (30.1% at 25 μg/ml). Our study provides an efficient method for preparing a PRF for use as a functional food ingredient.     

Juice of New citrus hybrids (Citrus clementina Hort. ex Tan.×C. sinensis L. Osbeck) as a source of natural antioxidants

Fruit juices of pigmented and non-pigmented new citrus hybrids obtained by crossing clementine cv. Oroval with different cultivars of blood oranges were analysed to determine parameters related to fruit quality (total soluble solids titratable acidity, pH), and the content of ascorbic acid, total phenolics, flavanones, anthocyanins and phenolic acids. Antioxidant properties were evaluated by oxygen radical absorbance capacity (ORAC), and inhibition of induced linoleic acid peroxidation (InLAP) assays. The results of this study show that some hybrids with high antioxidant activity owing to considerable polyphenol content may be considered rich sources of phytochemicals. The OTA 9 hybrid was shown to be richest in polyphenols, suggesting that consumption of OTA 9 fruit or juice could be useful in health promotion and a disease-preventing diet. Moreover, the juice of this hybrid could be used as raw material to produce antioxidant ingredients for dietary, pharmaceutical, or cosmetic purposes.     

锦橙皮膳食纤维抗氧化活性研究

目的:提取锦橙皮膳食纤维,研究其对O2-·、·OH、DPPH·三种自由基的清除作用。方法:采用复合酶法对膳食纤维进行提取,采用邻苯三酚自氧化法和Fronton反应对清除O2-·、·OH、DPPH·的效果进行了研究。结果:对O2-.清除率最高为46.28%,对.OH的IC50为3.27mg/mL,对DPPH.的IC50为5.66mg/mL。综上所述,锦橙皮膳食纤维对三种自由基都具有一定的清除作用。     

壳聚糖协同次氯酸盐对北碚447锦橙贮藏品质的影响

为探讨壳聚糖协同次氯酸盐对北碚447锦橙贮藏品质的影响,用壳聚糖、壳聚糖协同次氯酸钠、壳聚糖协 同次氯酸钙涂膜处理北碚447锦橙,每5 d测定1 次果实贮藏期间果肉中可溶性固形物、总糖、总酸质量分数和VC、 总黄酮、总酚含量等品质指标。结果表明：壳聚糖具有良好的果品品质保持作用,能较好地保持果实VC、总酚含 量以及总糖质量分数;同时,壳聚糖与次氯酸盐协同涂膜对北碚447锦橙品质保持作用明显优于单独使用壳聚糖, 其中0.01 g/mL壳聚糖＋200 mg/L Ca(ClO)2处理效果最显著,有效地延缓了贮藏期间果实品质的下降。说明壳聚糖协 同次氯酸钙能够有效提高北碚447锦橙的贮藏品质和延长其贮藏期。     

涂膜与冷激处理对柚类保鲜效果的研究

膜包装后常温(15～25℃)贮存,观察其保鲜效果;结果表明：经涂膜本文以琯溪蜜柚作为试材,通过魔芋液膜对蜜柚进行涂膜处理,并辅以冷激处理,PE薄与冷激处理的蜜柚其枯水率(10％左右)大大低于未经涂膜与冷激处理的对照组,且营养素的损耗明显降低。预计对蜜柚贮藏5个月,其枯水程度低,有效得防止蜜柚在贮藏中的枯水现象,延长了贮藏期。     

魔芋葡甘露聚糖-壳聚糖复合涂膜对北碚447锦橙贮藏品质的影响

为探究魔芋葡甘露聚糖-壳聚糖复合涂膜对北碚447锦橙贮藏品质的影响,分别采用0.5%魔芋葡甘露聚糖+1%壳聚糖复合涂膜,0.5%魔芋葡甘露聚糖涂膜和空白处理北碚447锦橙。以5 d为一个周期,15 ℃温度贮藏,共贮藏5个周期,测定贮藏期间果实的总糖、可滴定酸、V_C、固形物、总酚等指标。结果表明,复合涂膜处理可有效延缓果实品质的下降,与0.5%魔芋葡甘露聚糖涂膜和空白处理对比,复合膜组能够明显抑制果实总糖、可滴定酸、V_C、总黄酮、总酚含量的下降,减缓果实中丙二醛的积累,使锦橙保持了较好的果实品质。证明了复合涂膜处理相比单独0.5%KGM保鲜效果更好。     

Chemical Profile of Satureja Kitaibelii Wierzb. ex Heuff. Essential Oils: Composition of Satureja Kitaibelii Essential Oils

The essential oils from dried aerial parts of Satureja kitaibelii Wierzb. ex Heuff., collected at three various sites in Serbia, were analyzed by gas chromatography and gas chromatography/mass spectrometry. One hundred sixty-three components were identified in all investigated samples, 132 components in the oil from the site Devoja?ki grob, 124 components in the oil coming from Si?eva?ka klisura site, and 146 components in the oil from the site Viso?ka R?ana, accounting 97.3, 93.9, and 95.6% of the total oils, respectively. The most abundant component in the essential oils was geraniol amounting from 24.0 to 30.3%, making up about one-quarter of the total oils. Other representative compounds were identified as linalool (5.0–14.8%), limonene (4.3–7.9%), and caryophyllene oxide (4.4–5.2%) in all tested samples. The results suggested that essential oils of S. kitaibelii belong to the aliphatic monoterpene chemotype.     

茼蒿挥发油化学成分分析

利用气相色谱-质谱联用法对茼蒿挥发油成分进行了分析,经毛细管色变分离出了38种组分,并确认了32种成分,检出率达84.21%,并用气相色谱面积归一化法测定了各种成分的相对百分含量,其主要成分为4-甲基-2-戊烯、4-甲基-2,3-二氢呋喃、β-蒎烯、苯甲醛等。     

Comparative study on the antioxidant capacity and cholinesterase inhibitory activity of Citrus aurantifolia Swingle, C. aurantium L., and C. bergamia Risso and Poit. peel essential oils

Abstract: The interest in medicinal plant research and in the aroma‐therapeutic effects of essential oils in humans has increased in recent years, especially for the treatment of pathologies of relevant social impact such as Alzheimer's disease. The present study was taken up to evaluate the antioxidant capacity and the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activity of the peel essential oils from three Citrus species, C. aurantifolia Swingle, C. aurantium L., and C. bergamia Risso & Poit. Essential oils were analyzed by GC and GC‐MS and they contain mainly limonene, α‐pinene, β‐pinene, γ‐terpinene, and linalyl acetate. C. aurantifolia oil showed the highest radical scavenging activity on ABTS assay (IC₅₀ value of 19.6 μg/mL), while C. bergamia exhibited a good antioxidant activity evaluated by the β‐carotene bleaching test (IC₅₀= 42.6 μg/mL after 60 min of incubation). C. aurantifolia inhibited more selectively AChE. Obtained data suggest a potential use of Citrus oils as a valuable new flavor with functional properties for food or nutraceutical products with particular relevance to supplements for the elderly. Practical Application: The demonstrated antioxidant activity and procholinesterase properties of Citrus essential oils suggested their use as a new potential source of natural antioxidant to added as extra‐nutrient for using in food industries as a valuable new flavor with functional properties for food or nutraceutical products with particular relevance to supplements for the elderly.     

大型罗勒和柚子精油的成分分析及其抗氧化性

采用气相色谱-质谱(GC-MS)联用法对大型罗勒精油和柚子精油的化学成分进行分析,并采用DPPH自由基(DPPH·)清除法、ABTS自由基阳离子(ABTS⁺·)清除法对精油及其主要单体的抗氧化性能进行了研究。大型罗勒精油鉴定出46个化学成分,占总含量的84.07%,其主要成分为香叶醛(14.20%)、β-石竹烯氧化物(10.97%)、香橙醛(10.38%)和β-石竹烯(4.09%);柚子精油鉴定出48个化学成分,占总含量的92.24%,其主要成分为柠檬烯(43.88%)、石竹烯(22.09%)、葎草烯(4.57%)和γ-松油烯(4.41%)。结果表明,大型罗勒精油和柚子精油对DPPH·和ABTS⁺·均具有清除活性,其中大型罗勒精油和柚子精油清除DPPH·的IC₅₀值分别为3.96 mg/mL和23.22 mg/mL;清除ABTS⁺·的IC₅₀值分别为1.61 mg/mL和2.30 mg/mL。由此可知,大型罗勒精油和柚子精油可以作为一种较为安全的天然抗氧化物来源。     

不同方法提取代代花中挥发油成分的GC-MS分析

分别采用水蒸汽蒸馏法、回流法和超声法提取代代花中的挥发油成分,提取率分别为0.16%、2.18%和2.34%。再用气相色谱-质谱法（GC-MS）对挥发油成分进行分析,峰面积归一法确定各组分的相对含量。三种方法分别鉴定出55、34、29种化学成分,其中水蒸气蒸馏法以萜品醇（20.98%）、柠檬烯（11.67%）主,回流法以棕榈酸（20.61%）、9,12-十八碳二烯酸-2-氯乙胺（14.54%）为主,超声法以正二十四烷（11.32%）、正二十一烷（11.06%）、棕榈酸（8.76%）为主。结果表明：不同方法提取的挥发油的组成及含量存在差异,针对目标产物需要选择合适的提取方法,水蒸汽蒸馏法对无极性和弱极性的萜烯和萜醇类化合物提取效果较好,超声法和回流法对极性稍强的脂肪酸和酯类有明显的提取优势。     

萝卜籽油成分研究

日的：研究不同品种萝卜籽粗脂肪的含量及脂肪酸组成，并利用GC—MS分析不同品种萝卜籽挥发性成分的组成及含量。方法：用索氏提取法测定粗脂肪含量，用溶剂提取挥发油成分，用气相色谱-质谱联用仪进行定性分析，结合计算机检索技术，对化学成分进行分离鉴定，面积归一化法测定各成分的相对含量。结果：研究结果表明，具有较大的开发应用价值。NIST、WILEY化合物谱库检索，应用气相色谱峰萝卜籽含油高（≥30％），油中含不饱和脂肪酸多，具有较大的开发应用价值。     

Chemical Composition and Antimicrobial and Antioxidant Activities of Essential Oils and Various Extracts of Juniperus phoenicea L. (Cupressacees)

ABSTRACT:  GC-FID and GC-MS analysis of essential oils of  Juniperus phoenicea  resulted in the identification of 30 compounds, representing more than 98% of the total composition. α-pinene (55.7% and 80.7%), δ-3-carene (10.7% and 4.5%), and γ-cadinene (2.9% and 5.1%) were the main components, respectively, in leaves and berries essential oil. Extracts of  J. phoenicea  were obtained by different extraction solvents: methanol, ethanol, ethyl acetate, and dichloromethane and evaluated composition for polyphenols (gallic acid equivalent 52 to 217 g/kg), tannins (catechin equivalent 6.5 to 60.2 g/kg), antocyanins (cyanidin equivalent 84 to 373 mg/kg), and flavonoids (quercetin equivalent 6.4 to 29.3 g/kg). The samples (essential oils and extracts) were subjected to a screening for their antioxidant activity by using DPPH and ABTS assays; antimicrobial activity was tested with 6 bacteria (3 Gram-positive and 3 Gram-negative), 1 yeast, and 2 fungi. The strongest antioxidant activity was obtained by the methanolic extract ( IC ₅₀= 6.5 ± 0.3 mg/L). Flavonoids are likely to contribute to the antifungal activity against  Saccharomyces cerevisiae.  Correlations were studied between chemical composition and antioxidant and antimicrobial activities.     

四棱豆种子及其发酵物挥发性风味成分变化

采用气相色谱- 质谱的分析方法,对四棱豆种子及其发酵物挥发性成分变化进行分析,共鉴定出88 个化合物。结果表明：种子经微生物发酵后成分发生很大变化,同时产生大量新的挥发性成分,发酵前后只有苯乙醛、3,3,5- 三甲基环己酮两种完全相同的物质;在种子挥发性成分中含量较高的是醇类、酮类、烯烃类;种子发酵物主要挥发性成分是酯类、醚类、烯烃类。     

Essential oil of Teucrium scorodonia L. ssp. scorodonia from Italy

The essential oil of the flowering aerial parts of Teucrium scorodonia L. ssp. scorodonia growing in Italy on Verrucano, was analyzed by GC and GC–MS. All the identified compounds were sesquiterpene hydrocarbons. The main ones were germacrene B (26.2%) and β-caryophyllene (25.2%).     

Comparative GC/MS analysis of essential oils extracted by 3 methods from the bud of Citrus aurantium L. var. amara Engl

A comparative study of steam distillation extraction (SDE), reflux extraction (RE), and ultrasound-assisted extraction (USE) was conducted for the extraction of essential oils from the bud of Citrus aurantium L. var. amara Engl. Each method was evaluated in terms of qualitative and quantitative composition of the isolated essential oil by gas chromatography/mass spectrometry (GC/MS). The extract yields of essential oil were 0.16%, 2.18%, and 2.34%, respectively. A total of 82 compounds were identified by GC/MS. The main components obtained by SDE were terpinen-4-ol (20.98%), dipentene (11.67%), terpinene (9.24%), those by RE were palmitic acid (20.61%), 2-chloroethyl linoleate (14.54%), tetracosane (12.26%), and α-linolenic acid (11.24%), and those by USE were tetracosane (11.32%), heneicosane (11.06%), and palmitic acid (8.76%). Comparative analysis indicated that SDE was favorable for the extraction of monoterpene hydrocarbons, sesquiterpene hydrocarbons, alcohols, and carbonyl compounds, RE and USE had certain advantages in the extraction of aliphatic saturated hydrocarbons, organic acids, and esters. It is concluded that different extraction methods may lead to different yields of essential oils; the choice of appropriate method is very important to obtain more desired components with higher physiological activities. PRACTICAL APPLICATION: C. aurantium oils from different plant parts have great economic, medicinal, and nutritional values because of their wide-spectrum biological activities. The essential oil from C. aurantium L. var amara is one of the best C. aurantium oils. The data presented in this article will help us understand the relationship between essential oils and its extraction methods and know more about the aromatic components of Citrus aurantium bud. The methods established in this study will provide useful reference information for further studies, and offer essential oil industries with helpful guidance in practice.     

Essential oil composition of Pistacia lentiscus L. and Myrtus communis L.: Evaluation of antioxidant capacity of methanolic extracts

The seasonal variation of the essential oil composition, the antioxidant activity (DPPH, FRAP assays) and the total phenolic content (Folin-Ciocalteu assay) of two aromatic wild plants, Pistacia lentiscus L. (Anacardiaceae) and Myrtus communis L. (Myrtaceae), grown in Zakynthos, a Greek island, was investigated. The essential oil was obtained by hydrodistillation and subsequently analysed by GC–MS.