Citrus bitterness

XXXV) 1 3 - imi the fall poison pierotoxiain (XXXVI), ae well as coriamyrtin1 73 and related substanoes the citrus bitter principle limonin (XXXVII) and the related substances nomilin and obaou-none 4" and the terpenoid substances clerodin1 7.1 and oedre-kne.im.iMa... 

Example Formula for Citrus Bitter Liqueur (36% v/v) Step 1 Citms Bitter Extract, 40% v/v... 

Jourdan PS, Mansell RL, Weiler EW (1982) Radioimmunoassay for the citrus bitter principle, naringin, and related flavonoid-7-0-(3-neohesperidosides. J Med Plant Res 44 82-86... 

Liu Y, Alford AR, Rajab MS, Bentley MD (1990) Effects and modes of action of citrus limonoids against Leptinotarsa decemlineata. Physiol Entomol 15 37-45 Maier VP, Beverly GD (1968) Limonin monolactone, the nonbitter precursor responsible for delayed bitterness in certain citrus juices. J Food Sci 33 488-492 Maier VP, Grant ER (1970) Specific thin-layer chromatography assay of limonin, a citrus bitter principle. J Agric Food Chem 18 250-252... 

Matsumoto R, Okudai N (1991a) Early evaluation of citrus bitter component, flavanone neohesperidosides by enzyme immunoassay using anti-naringin antibody. J Jpn Soc Hortic Sci 60 191-200... 

Citrus aurantium L., syn. Citrus Bitter orange oil NeroU oil, Bitter orange Flower, pericarp, leaf, and... 

Since the determination of the structure of the citrus bitter principle limonin in 1960, the number of structurally defined members of this class of natural products (now called limonoids) has grown to several hundred. Corey s group reported the first enantioselective synthesis of a limonoid, the protolimonoid, by a route which is both short and stereo-controlled (Scheme 9.45) [17j]. Brief exposure of chiral epoxide 35 to 1.2 equiv of MeAlCl at -78°C provided two diastereomeric tricyclic ketones in a 1.5 1.0 ratio with ketone 36 as the minor component. The predominating dia-stereomer in the mixture, in which the appendage a to the carbonyl is axially oriented, could be isomerized to 36 by treatment of the crude mixture with sodium ethoxide in ethanol. Overall, the cationic cyclization and epimerization permit the rapid stereoselective establishment of three rings and five stereocenters in 43% yield. Slow addition of a solution of AIBN and BUjSnH to a heated solution of xanthate... 

Orange Flower (Neroli) Oil. "The rose we call the queen of flowers, the jasmin the fairest and prettiest princess, but the orange flower is the most fragile and dainty of out royal family of flowers. If the rose stirs our memories, the jasmin our hopes, the orange flower stirs sentiments—sentiments most romantic " (14). Commercial neroh oil [8016-38 J is obtained by steam distillation of the freshly picked blossoms of the bitter orange Citrus aurantium L. subspecies amara, which is cultivated in Mediterranean countries as well as in Haiti and several other tropical countries. More than 125 components have been identified in the oil the principal ones are shown in Table 4 and Figure 1. 

Mondello et al. (54) have developed some applications of on-line HPLC-HRGC and HPLC-HRGC/MS in the analysis of citrus essential oils. In particular, they used LC-GC to determine the enantiomeric ratios of monoterpene alcohols in lemon, mandarin, bitter orange and sweet orange oils. LC-GC/MS was used to study the composition of the most common citrus peel, citrus leaf (petitgrain) and flower (neroli) oils. The oils were separated into two fractions, i.e. mono- and sesquiterpene... 

Bar-Peled M, Lewinsohn E, Fluhr R, Gressel J (1991) UDP-rhamnose flavanone-7-0-glucoside-2"-0-rhamnosyltransferase purification and characterization of an enzyme catalyzing the production of bitter compounds in Citrus. J Biol Chem 266 20953-20959... 

Frydman A, Weisshaus O, Bar-Peled M, Huhman D, Summer L, Matin F, Lewinsohn E, Fluhr R, Gressel J, Eyal Y (2004) Citrus fruit bitter flavors isolation and functional characterization of the gene Cml,2RhaT encoding a 1,2rhamnosyltransferase, a key enzyme in the biosynthesis of the bitter flavonoids of Citrus. Plant J 40 88-100... 

Aegle marmelos Correa) and bitter orange Citrus aurantium), has also been demonstrated to possess potent antidiabetic and antihyperlipidemic effects. 

We know of thousands of flavonoids. They have a C6-C3-C6 skeleton and are responsible for the bright colors in flowers. The bitter taste in citrus fruits is caused by flavonone glycosides. 

Grapefruit oil is obtained by cold pressing of the outer peels of the fruits of Citrus paradisi Macfad. (Rutaceae). It is a greenish-yellow liquid, with an odor resembling that of sweet orange oil, but more herbaceous and bitter. 

Bitter orange oil is obtained by pressing fresh peel from the fruits of Citrus aurantium L. subsp. aurantium (Rutaceae). It is produced mainly in Mediterranean countries and is a pale yellow to yellowish-brown liquid with a slightly mandarinlike odor and a somewhat bitter aroma. 

Petitgrain oils are obtained by steam distillation of the leaves of citrus trees. The oils derived from the bitter orange tree are the most important. Other petitgrain oils (mandarinier, citronnier, and bergamottier) are less important. Petitgrain oil mandarinier is a source of natural methyl A -methylanthranilate, which is present at a concentration of nearly 50%. Petitgrain oils are essential constituents of eau de cologne. 

Petitgrain oil Paraguay is obtained from an acclimatized variety of the bitter orange tree. Citrus aurantium L. subsp. aurantium, which is grown in Paraguay. It is pale yellow liquid with a characteristic, strong, pleasant odor, reminiscent of linalool and linalyl acetate. 

Bitter orange Citrus aurantium (Rutaceae) (+)-hmonene, geranial... 

Manners GD, Breksa AP III, Schoch TK, Hidalgo MB. Analysis of bitter limonoids in citrus juices by atmospheric pressure chemical ionization and electrospray ionization liquid chromatography-mass spectrometry. J Agric Food Chem 2003 51(13) 3709-3714. 

Citrus aurantium (Christen.) Swingle var. amara Suan Cheng (Bitter orange) (unripe fruit) Synephrine, N-methyltyramine, flavones including tangeratin and nobiletin.33 Treat indigestion, relieve abdominal distension, ptosis of the anus or uterus. 

Flavones contribute to plant tissue color provided that they occur in high concentrations or are complexed with metal ions. Some flavones participate in taste for example, the highly methoxylated aglycones nobiletin, sinensetin and tangeretin are responsible for the bitter taste of citrus peel. On the other hand, some glycosylated flavones (for instance neodiosmin and rhoifolin) reduce the bitterness of some substances (limonin, naringin, caffeine, quinine) [2]. 

BERGAMOT OIL. An essential oil, Brownish-yellow to green liquid, agreeable odor, bitter taste, produced from the nnd of the fruit of Citrus aurantium or C. bergamia, relatives of the orange and lemon, The small trees are cultivated in southern Europe. The oil is expressed from the skin of the small yellow fruits and sometimes is used as a scent for cosmetics. The oil also is used sometimes as a clearing agent in the preparation of material for microscopic examination. 

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