Citrus aurantium, an ingredient of dietary supplements marketed for weight loss: current status of clinical and basic research

Seville orange (Citrus aurantium) extracts are being marketed as a safe alternative to ephedra in herbal weight-loss products, but C. aurantium may also have the potential to cause adverse health effects. C. aurantium contains synephrine (oxedrine), which is structurally similar to epinephrine. Although no adverse events have been associated with ingestion of C. aurantium products thus far, synephrine increases blood pressure in humans and other species, and has the potential to increase cardiovascular events. Additionally, C. aurantium contains 6',7'-dihydroxybergamottin and bergapten, both of which inhibit cytochrome P450-3A, and would be expected to increase serum levels of many drugs. There is little evidence that products containing C. aurantium are an effective aid to weight loss. Synephrine has lipolytic effects in human fat cells only at high doses, and octopamine does not have lipolytic effects in human adipocytes.     

Aurantii Fructus: a systematic review of ethnopharmacology,phytochemistry and pharmacology

Phytochemistry Reviews - Aurantii Fructus (called Zhiqiao, ZQ in Chinese), the dried unripe fruit of Citrus aurantium L. or its cultivated variety, is a common traditional edible-medicinal herb in...     

Comparative study of the composition of waxes extracted from isolated leaf cuticles and from whole leaves of Citrus: Evidence for selective extraction

The effect of different extraction methods on the composition of samples of soluble cuticular lipids (SCL) of Citrus aurantium L. was investigated. The variation of extraction yields, when whole leaves were immersed in solvent, was studied as a function of solvent type and duration of immersion. Cuticular waxes were also quantitatively extracted from isolated cuticular membranes of C. aurantium and their composition was compared to that of samples obtained by the immersion method. Significant differences were observed. Higher carbon number homologues of the aliphatic constituent classes were discriminated against when whole C. aurantium leaves were extracted by immersion. The alkyl ester fraction was almost entirely lacking in extracts from whole leaves. The dependence on carbon chain length of the saturation concentrations in chloroform of major aliphatic SCL constituents was determined. The results are discussed in terms of the major physico-chemical processes involved in the extraction of SCL.     

Toxic effects of six plant oils alone and in combination with controlled atmosphere on Liposcelis bostrychophila (Psocoptera: Liposcelididae).

Six plant essential oils alone as repellent and fumigant, and in combination with the controlled atmosphere against Liposcelis bostrychophila Badonnel were assessed in the laboratory. These essential oils were extracted from the leaves of six source plants: Citrus tangerina Tanaka, Citrus aurantium L., Citrus bergamia Risso et Poiteau, Pinus sylvestris L., Cupressus funebris End]., and Eucalyptus citriodora Hook. The repellency test indicated that L. bostrychophila adults were repelled by filter paper strips treated with six essential oils. Of these essential oils, the C. funebris oil was most effective followed by that of F. sylvestris, C. tangerina, C. bergamia, and E. citriodora. The average repellency of the C. aurantium oil against L. bostrychophila adults was significantly lower than other five test oils by day 14. These essential oils had a high level of toxicity in the fumigation assay against L. bostrychophila adults at both 10 and 20 ppm. When combined with two controlled atmosphere treatments (12% CO2 + 9% O2, and 10% CO2 + 5% O2, balanced N2), the toxicity of plant oils was enhanced significantly.     

植物精油对几种害虫的毒杀活性

对 11科 15属 2 7种植物精油的杀虫活性做了测定。八角茴香果实、柠檬果实、细叶桉叶和留兰香叶精油对粘虫、小菜蛾、棉铃虫和玉米象有较强的熏蒸活性 ;精油稀释 10 0倍后 ,甜橙果实、玳玳花和砂地柏精油对粘虫的拒食活性最高 ;在 0 4% (w/w)剂量下 ,肉桂皮和八角茴香果实等 7种精油对玉米象的种群形成抑制率达 10 0 %。     

Adverse reaction to an adrenergic herbal extract (Citrus aurantium)

We report the case of a 52 year old woman that had an adverse reaction after taking a dry herbal extract of an unripe fruit of Citrus aurantium L. var. amara, as dietary supplement for weight loosing. The fruit is also known as zhi shi (in traditional Chinese Medicine) or bitter orange in other parts of the world.     

苦橙叶精油化学成分及抗炎作用研究

为探究苦橙叶精油的抗炎作用。实验采用气相-质谱联用法(GC-MS)分析精油成分,并建立脂多糖(LPS)诱导RAW 264.7细胞炎症模型,用Griess法检测一氧化氮(NO)含量评价其体外抗炎作用,随后进一步通过巴豆油致小鼠耳肿胀模型和鸡蛋清致小鼠足肿胀模型评价其体内抗炎作用。结果表明苦橙叶精油成分以酯类、醇类物质为主;25μg/mL浓度能显著抑制RAW 264.7细胞NO的释放;中浓度苦橙叶精油能明显减轻小鼠耳肿胀程度;低、中、高浓度苦橙叶精油均对小鼠足肿胀模型有炎症缓解作用,并于肿胀前期呈浓度依赖性。以上实验证明苦橙叶精油在体外和体内具有一定抗炎作用。     

The Chemical Components of Essential Oils from the Leaves of 110 Species and Cultivars of Citrus Plants

Seventy-two chemical components of essential oils from the leaves of 110 species and cultivars of Citrus were analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Among the plants analyzed, there are 3 species in papeda, 12 species and cultivars in Osmocitrus, 18 cultivars in C. aurantium L., 15 cultivars in C. sinensis Osbeck, 16 species and cultivars in Citrophorum, 16 species and cuhivars in Cephalocitrus, 30 species and cultivars in Acrumen. As resources of essential oils, some valuable plants were found such as Citrus hystrix D. C., C. junos (Sieb.) Tan. cv. Xiecheng, C. junos (Sieb.) Tan. cv. Luohancheng and C. tankan Hayata. Our study has provided systematic data of the chemical components of the essential oils for the taxonomic work of Citrus plants.     

柑桔细胞电融合再生两个种间体细胞杂种

朋娜脐橙(Citrussinensis Osbeck)胚性细胞悬浮系原生质体分别与粗柠檬(C.jambhiri Lush)、枸头橙(C.aurantium)叶肉原生质体经电场诱导而融合。经培养,两组合均获得再生植株。对朋娜脐橙+粗柠檬的再生胚状体进行染色体计数,随机取样的52个胚状体中,26个为四倍体,另外26个为二倍体;对74棵再生植株进行染色体计数,由此说明都为四倍体;表明体细胞杂种在植株再生过程中具有明显的竞争优势。朋娜脐橙+枸头橙再生的14棵植株都为四倍体。对朋娜脐橙+粗柠檬部分植株进行POX同工酶和RAPD分析,表明所有检测植株都为杂种。朋娜脐橙+枸头橙再生植株经RAPD分析,表明也为杂种。     

The introduction of cultivated citrus to Europe via Northern Africa and the Iberian Peninsula

The circumstances concerning the diffusion of the main cultivated citrus from their places of origin in Asia are studied here, showing that the citron (’Citrus medica L.) was the only one knew in Ancient times in Europe, while the lemon (C. limon [L.] Osbeck), lime (C. aurantiifolia [Christm.] Swingle), pomelo (C. maxima [Burm.] Merr.) and sour orange (C. x aurantium L.) were introduced to Europe by the Muslims via the Iberian Peninsula and Sicily, and that the grapefruit (C. paradisi Macfad.), mandarin (C. reticulata Blanco) and sweet orange (C. x aurantium L.) arrived to the West between the fifteenth and nineteenth centuries as a result of the trade with the British and Portuguese colonies.     

Effects of the essential oil from Citrus aurantium L. in experimental anxiety models in mice

Citrus aurantium L. is popularly used to treat anxiety, among other indications suggesting central nervous system action. Previous studies showed anxiolytic effect in the essential oil from peel in mice evaluated on the elevated plus maze [Carvalho-Freitas, M.I.R., Costa, M., 2002. Anxiolytic and sedative effects of extracts and essential oil from Citrus aurantium L. Biological and Pharmaceutical Bulletin 25, 1629-1633.]. In order to better characterize the activity of the essential oil, it was evaluated in two other experimental models: the light-dark box and the marble-burying test, respectively related to generalized anxiety disorder and to obsessive compulsive disorder. Mice were treated acutely by oral route 30 min (single dose) or once a day for 15 days (repeated doses) before experimental procedures. In light-dark box test, single treatment with essential oil augmented the time spent by mice in the light chamber and the number of transitions between the two compartments. There were no observed alterations in the parameters evaluated in light-dark box after repeated treatment. Otherwise, single and repeated treatments with essential oil were able to suppress marble-burying behavior. At effective doses in the behavioral tests, mice showed no impairment on rotarod procedure after both single and repeated treatments with essential oil, denoting absence of motor deficit. Results observed in marble-burying test, related to obsessive compulsive disorder, appear more consistent than those observed in light-dark box.     

Development of SSR markers from Citrus clementina (Rutaceae) BAC end sequences and interspecific transferability in Citrus

? Premise of the study: Microsatellite primers were developed from bacterial artificial chromosome (BAC) end sequences of Citrus clementina and their transferability and polymorphism tested in the genus Citrus for future anchorage of physical and genetic maps and comparative interspecific genetic mapping. ? Methods and Results: Using PAGE and DNA silver staining, 79 primer pairs were selected for their transferability and polymorphism among 526 microsatellites mined in BES. A preliminary diversity study in Citrus was conducted with 18 of them, in C. reticulata, C. maxima, C. medica, C. sinensis, C. aurantium, C. paradisi, C. lemon, C. aurantifolia, and some papedas (wild citrus), using a capillary electrophoresis fragment analyzer. Intra- and interspecific polymorphism was observed, and heterozygous markers were identified for the different genotypes to be used for genetic mapping. ? Conclusions: These results indicate the utility of the developed primers for comparative mapping studies and the integration of physical and genetic maps.     

A Study on Chemical Components of Essential Oils from Citrus bergamia and Its Close Relatives and Its Taxonomy

Citrus bergamia Risso. is a rare perfumery plant. Taxonomists have different views on the taxonomy of C. bergamia. Chemical components of leaf and peel essential oils from C. bergamia, and its close relatives, C. limon, C. aurantifolia and three varieties of C. aurantium, were analyzed by GC and GC-MS. The analytical result shows that the chemical compositions of the leaf essential oils from C. bergamia are basically the same as those from three varieties of C. aurantium. Their main components are linalool (29.19-39.75% )and linalyl acetate (24.73-30.24% )etc., and contents of other components are also similar. But their peel essential oils are different. The peel essential oils from C. bergamia contain less limonene (29.94%) than those from C. aurantium (92.55-94.31% ) and less beta-pinene (3.00%) and y-terpinene(3.48% )than those from C. limon or C. aurantifolia (respectiyely 9.16% and 10.42% ) . The peel essential oils from C. bergamia contain not only as much linalool (22.20%) and linalyl acetate (32.66%)as those in the leaf essential oils from C. aurantium, but also as much limonene(29.94% )as that in the peel essential oils from C. limon or C. aurantifolia . The contents of limonene are close to those of the essential oils from C. aurantifolia. This result shows that C. bergamia may be a natural hybrid between C.aurantium and C. aurantifolia, as proposed by Sinclair W. B.     

Isolation of antioxidative phenolic glucosides from lemon juice and their suppressive effect on the expression of blood adhesion molecules

Phenolic glucosides having radical scavenging activity were examined from the fraction eluted with 20% methanol on Amberlite XAD-2 resin applied to lemon (Citrus limon) juice by using reversed phase chromatography. Four phenolic glucosides were identified as 1-feruloyl-beta-D-glucopyranoside, 1-sinapoyl-beta-D-glucopyranoside, 6,8-di-C-glucosylapigenin and 6,8-di-C-glucosyldiosmetin by (1)H-NMR, (13)C-NMR, and MS analyses. They exhibited radical scavenging activity for 1,1-diphenyl-2-picrylhydrazyl (DPPH) and superoxide, although the activity was low in comparison with eriocitrin, a potent antioxidant in lemon fruit, and the eriodictyol of its aglycone. The phenolic compounds in lemon juice were examined for their suppressive effect on the expression of blood adhesion molecules by measuring the expression of intercellular adhesion molecule-1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) induced by necrosis factor-alpha (TNF-alpha). 6,8-Di-C-glucosylapigenin, apigenin, and diosmentin of the flavones were found to significantly suppress the expression of ICAM-1 at 10 muM (P<0.05). The phenolic glucosides isolated in this study were contained in comparative abundance in daidai (Citrus aurantium) and niihime (Citrus unshiu x Citrus tachibana) among the sour citrus juices.     

High-performance liquid chromatography methods for the analysis of adrenergic amines and flavanones in Citrus aurantium L. var. amara

Reverse-phase HPLC coupled with photodiode array detection was used for the simultaneous separation and determination of naturally occurring adrenergic amines (octopamine, synephrine and tyramine) in fruits and dry extracts of Citrus aurantium L. var. amara and in herbal medicines derived therefrom. Synephrine was the main component in fruits (0.10-0.35%) and in dry extracts (3.00-3.08%) and was present in the range 0.25-0.99% in herbal medicines. Flavanones were analysed in the same samples using a reverse-phase HPLC technique which allowed the identification and quantification of neoeriocitrin, narirutin, naringin, hesperidin, neohesperidin, naringenin and hesperetin. C. aurantium fruits and derivatives contained mainly glycosylated flavanones: in particular, naringin and neohesperidin were found to be the major flavonoids and their concentrations ranged from 1.80 to 26.30 and from 3.90 to 14.71 mg/g, respectively. The levels of aglycones were very low in all samples tested.     

The Chemical Constituents of the Essential Oil from the Flowers,Leaves and Peels of Citrus aurantium

Citrus aurantium L. var. amara Engl., is a better species of sour oranges. There are essential oils in the flowers, the peels, the leaves and the branches of C. aurantium. The flower oil can be used in the preparation of perfumes of high quality. The peel oil is used mainly for the flavor-endowing of soft drinks, alcoholic drinks, bread, confectionaries and cakes. In order to control the quality of the essential oils and to improve them, we have systema- tically studied the chemical constituents of the flowers, the leaves and the peals of C. aurantium with our preparation. 12 main components were separated by silica gel column chromatography. The following 33 chemical components were identified by IR, GC-MS and GC retention index: α-thujene, α-pinene, camphene, β-pinene, myrcene, limonene, β-ocimene, trans-linalooloxide (furanoid), cis-linalooloxide (furanoid), linalool, 1,4-p-methadien-7-ol, trans-pinocarveol, camphor, terpinen-4-ol α-terpineol, nerol, citral-b, geraniol, linalylacetate, citrala, trans-linalooloxide (pyranoid), methyl anthranilate, terpinyl acetate, cis-linalooloxide (pyranoid), neryl acetate. geranyl acetate, nonanal, β-caryophyllene, α-humulene, γ-muurolene, β-nerolidol, farnesol, α- nerolidol. GC retention index of 33 compounds were measured. A fast method for routine determination is presented.     

Insecticidal activity of Citrus aurantium fruit, leaf, and shoot extracts against adult olive fruit flies (Diptera: Tephritidae)

Solvent extracts of differing polarity from Citrus aurantium (L.) (Rutaceae) fruit, leaves, and shoots were evaluated for biological activity against adults of the olive fruit fly, Bactrocera oleae (Gmelin) (Diptera: Tephritidae). Using a petri dish residual exposure bioassay, we found that the petroleum ether extract from fruit alone showed insecticidal activity against the flies. The extract of the three fruit tissues (flavedo [peel], albedo, and flesh) indicated that bioactivity was limited to the flavedo, and this activity was significantly higher than that of the whole fruit extract. The most effective extract was obtained when fresh flavedo was used, whereas extracts of oven-dried flavedo were inactive. Fruit maturity also affected bioactivity; extracts of ripe fruit were more effective than those of unripe fruit. Our results suggest that C. aurantium flavedo contains secondary metabolites with insecticidal activity against B. oleae adults.     

Elevated CO2 effects on stomatal density of wheat and sour orange trees

No significant differences were found in stomatal densitiesor stomatal indices of wheat or sour orange trees grown at highCO₂ concentrations in two different CO₂ enrichment systems (Free-AirCO₂ Enrichment for wheat and Open-Top Chambers for orange trees).These results are in accordance with most of the previous resultsobtained in short-term experimental studies which suggest thatplants do not acclimate to increasing CO₂ concentration by changingstomatal density within a single generation. Key words: Triticum aestivum, Citrus aurantium, stomatal density, elevated atmospheric CO₂     

Simultaneous extraction of bioactive limonoid aglycones and glucoside from Citrus aurantium L. using hydrotropy

Citrus limonoids were demonstrated to possess potential biological activities in reducing the risk of certain diseases. Limonoids are present in citrus fruits in the form of aglycones and glucosides. At present, limonoid aglycones and limonoid glucosides are extracted in multiple steps using different solvents. In order to understand their potential bioactivity, it may be beneficial to isolate and purify these compounds using environment friendly methods. A new method of extraction and purification of limonoids was established using a hydrotrope polystyrene adsorbent resin. Extraction of aglycones and glucosides was achieved in a single step, using an aqueous solution of sodium cumene sulphonate (Na-CuS). Sour orange (Citrus aurantium L.) seed powder was extracted with 2 M Na-CuS solution at 45 degrees C for 6 h. The filtered extract was diluted with water and loaded on an SP 700 adsorbent column. The column was washed with distilled water to remove the hydrotrope and then eluted using water and methanol in different compositions to obtain three compounds. The structures of the isolated compounds were confirmed by NMR spectroscopy as deacetyl nomilinic acid glucoside (DNAG), deacetyl nomilin (DAN) and limonin (LIM).