Citrus phenolics

Fan J, Johnson MH, Lila MA, Yousef G, de Mejia EG (2013) Berry and citrus phenolic compounds inhibit dipeptidyl peptidase IV implications in diabetes management. Evid Based Complement Altemat Med 2013 479505... 

The other class of acrylic compatible tackifiers includes those based on ter-penes. Terpenes are monomers obtained by wood extraction or directly from pine tree sap. To make the polyterpene tackifiers, the monomers have to be polymerized under cationic conditions, typically with Lewis acid catalysis. To adjust properties such as solubility parameter and softening point, other materials such as styrene, phenol, limonene (derived from citrus peels), and others may be copolymerized with the terpenes. 

Marsh grapefhiit (MGF) pulp was homogenized in 5 volumes of extraction buffer at 4 C and maintained at pH 8.0 (28). The homogenate was stirred for one hour, centrifuged and the supernatant used as the PE extract. Activity was measured by titration with a Brinkman (Westbury, NY) pH stat titrator at pH 7.5 and 30°C in 25 mL of 1 % high methoxyl pectin (Citrus Colloids Limited, Hereford, UK) with O.IM NaCl. PE units are expressed as the microequivalents of ester hydrolysed per minute. Uronic acid analyses were conducted based on the m-phenyl phenol (4) as modified for microplate reading (30). 

The flavanone hesperetin has been detected in citrus honeys but not in honey samples of any other origins (Ferreres et al., 1993). It is a constitutive phenolic compound of citrus nectar, where it is present as a glycoside (hesperidin). 

Feldman, A.W. and Hanks, R.W. (1968). Phenolic content in the roots and leaves of tolerant and susceptible citrus cultivars attacked by Rodopholus similis. 

Bocco A, Guvelier ME, Richard H and Berset C. 1998. Antioxidant activity and phenolic composition of citrus peel and seed extracts. J Agric Food Chem 46 2123-2129. 

Berhow M, Tisserat B, Kanes K, Vandercook C (1998) Survey of phenolic compounds produced in Citrus. USDA ARS Technical Bull 158... 

Oufedjikh H, Mahrouz M, Amiot MJ, Lacroix M (2000) Effect of gamma-irradiation on phenolic compounds and phenylalanine ammonia-lyase activity during storage in relation to peel injury from peel of Citrus Clementina Hort. ex. Tanaka. J Agric Food Chem 48(2) 559-565... 

Such a system has been used for the comprehensive 2D chromatography of proteins [9,14], synthetic polymers [16], oxygen heterocyclic fraction of cold-pressed citrus oils [22,29], carotenoids [39], triglycerides in fats and oils [18-21], pharmaceuticals [29], and acidic and phenolic compounds [27,28]. 

Botanically speaking, citrus is a hesperidium, a berry with a leathery aromatic rind and a fleshy interior divided into sections. As shown by the cross section shown in Fig. 6.1, the exo carp or peel consists of an outer layer called the flavedo which contains oil glands and pigments and a white spongy inner layer called the albedo. The fleshy interior or endocarp of the fruit consists of wedge-shaped sections (segments) filled with multiple fluid-filled sacs or vesicles. These juice sacs constitute the edible portion of a citrus fruit. The cytoplasm contents provide the primary source of the citrus juice. The juice consists primarily of water, sugars, pectins, lipids, terpenes, amino acids, phenolics, carotenoids and minerals. 

PHENOLIC COMPOUNDS IN GRAPEFRUIT AND CITRUS WITH POTENTIAL DRUG INTERACTIONS... 

A major group of citrus compounds interacting with drugs are phenolics, which include hydroxycinnamic acids, flavonoids such as flavanones, fla-vones, and flavonols, and anthocyanins, as well as coumarins (Table 1, Fig. 1) (30). Many of these phenolic compounds have been shown to have antioxidant and anticancer properties that may play an important role in cancer prevention, but also in prevention of other chronic diseases such as coronary heart disease, gout, and arthritis (58 60). 

Table 1 Examples of Phenolic Compounds in Selected Citrus Varieties with Drug Interactions...

Phenolic compound Citrus variety Drug- interaction... 

Names of phenolics include their conjugated forms which occur in citrus. Abbreviations, an, animal study C, citrus hm, human trial vt, in vitro study. Source From Refs. 30-40. 

For several phenolics from citrus, such as eriocitrin, poncirin, and sinapic acid and anthocyanins, which occur in red grapefruit varieties and blood oranges, no specific drug interactions and also no interactions with CYP3A4 and P-gp are reported. 

Berhow MTB, Kanes K, Vandercook C. Survey of Phenolic Compounds Produced in Citrus. Technical Bulletin Number 1856. United States Department of Agriculture, 1998. 

Swatsitang, P., Tucker, G., Robards, K., and Jardine, D. 2000. Isolation and identification of phenolic compounds in Citrus sinensis. Anal. Chim. Acta 417 231-240. 

Since phenolic compounds occur in many fruits and most of them contribute to color and taste, phenolic analysis of fruits has been an active research area, especially in apple, grape, and citrus fruits and their products, such as juice, cider, and wine. 

Neohesperidin dihydrochalcone (NeoDHC) is a phenolic compound prepared from the bitter citrus flavanones naringin and neohesperidin (Horowitz Gentili, 1985). NeoDHC is a white solid with solubility in water of 0.5 g/1, which increases with temperature, but as use level is low, sufficient for most applications. 

The total nitrogen of orange juices was found to increase with the maturity of the fruit and ranged between. 068 to. 120 g per 100 ml (30). The actual protein values obtained by Clements (31) were about 20 percent of the acetone powder. Nearly 30 percent of the alcohol-insoluble solids of juice and about 20 percent of that of vesicular pulp were found to be protein as determined by the Kjeldahl procedure (32). These values are the actual protein that was precipitated by alcohol and are only a fraction of the total protein values usually reported for orange juice (8). The main source of proteins in citrus juice is probably in the form of enzymes and the plastids. At least 47 different enzymes have been reported to occur in citrus fruits (33). Citrus fruits also contain several phenolic amines (34), some of which such as syn-epherine, may have physiological importance (35). 

Phenolics. The phenolics of citrus represent a varied and widely studied class of compounds. They range from the lipid-soluble methoxylated coumarins and psoralens to the water-soluble glycosides of the flavanones and flavones. They include the intensely bitter naringin and the highly insoluble hesperidin. Different classes within the group have characteristic UV spectra which have been used to detect adulterations in juices and oils. 

Phenols and derivatives are the main aromatic compounds of plants, whose structural formulas contain at least one benzene ring. They serve as odors, fungicidals, or germination inhibitors. Coumarins are especially common in grasses, orchids, citrus fruits, and legumes. Plants containing phenols with anticancer properties include the following ... 

Phenolic acid Inhibits nitrosamines enhances enzyme activity Berries, broccoli, cabbage, carrots, citrus fruits, eggplant, parsley, peppers, teas, tomatoes, whole grains... 

Synonym Bayer 37344, Draza, Ensurol, Mercaptodimethur, Mesurol, Mesurol Phenol, metmercapturon Chemical Name 4-methylthio-3,5-xylyl methylcarbamate 3,5-di methyl-4-(methylthio)phenol methylcarbamate Uses Insecticide/Acaricide/Molluscicide/Repellent to control slugs and snails in a wide range of agricultural situations broad range control of lepidoptera, coleoptera, diptera, and homoptera and spider mites in pome fruit, stone fruit, citrus fruit, strawberries, hops, potatoes, beet, maize, oilseed rape, vegetables and ornamentals also used as a bird repellent. 

Fig. 1. Distribution of radioactivity among phenolic amines during 3 months after feeding [l-14C]tyramine to a Cleopatra mandarin seedling. ( — ) Hordenine, (0—0) synephrine, (O—O) AJ-methyltyramine, and (O—O) tyramine. (Reprinted with permission from Phytochemistry, Vol. 8, T. A. Wheaton and 1. Stewart, Biosynthesis of synephrine in citrus. Copyright 1969, Per-gamon Journals Ltd.)...

The effects of biochemical use are at various folds, but the major direct substation of biochemicals for petrochemicals is found at the upstream of chemical production processes. For instance, the oil distraction from crops is far less harmful than the oil extraction from petroleum. In the case of phenol, making phenol from plants is estimated to generate 80 percent less pollutants than making phenol from petroleum. Another example is limonene. Limonene derived from citrus fruit... 

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