LEMON PEEL EXTRACT

Description

One of the possible definitions of Lemon peel extract is Lemon bioflavonoid complex which is a hygroscopic dried powder of lemon peel extract containing the water-soluble flavonoids and associated complex extractives. A typical preparation contains about 35% of mono- and disaccharides (chiefly glucose, fructose, and sucrose), 15% ash, 9-12% calcium citrate, 1.5-3.0% citric acid, about 4-7% bioflavonoids and unspecified amounts of inositol and other organic acids. The most plentiful flavonoid is hesperidin, with lesser amounts present of eriocitrin, naringen rutinoside, diosmin, the 7-rutinosides ofluteolin and apigenin, and rutin. The rutin content of this preparation ranges from 240-640 μ/g with an average of 440 μ/g. No free quercetin was detected.
According to the FDA, lemon bioflavonoid complex (lemon peel infusion) is the dried concentrate of water soluble flavonoids from washed, deoiled (cold pressed), ground lemon peel. Citrus fla vonoids consist of the dried concentrate of water soluble flavonoids from washed, deoiled, group peel and pulp of oranges, grapefruit, and tangerines for use in special dietary foods in amounts up to 600 milligrams daily.
In general, flavonoids comprise a group of naturally occurring compounds which are among the most ubiquitous in the plant kingdom. They are found in every family and in nearly every species of the higher plants. It has been reported that about 800 different flavonoids were known and that new members of the group were being discovered "nearly every month." Although the term implies a yellowish coloration, flavonoids may vary in appearance from colorless to red or blue.
The basic flavone structure consists of 1,4-benzopyrone with a phenyl substitution in the 2-position. Flavonoids differ in the number and position of substitutions on the aromatic rings and in the extent and character of oxidation in the pyrone portion of the molecule. Hydroxyl groups enable flavonoids to combine with sugars to form glycosides, and it is in this form that the flavonoids are usually found in nature. Glucose is the most common prosthetic group, although other sugars, as well as glucuronic and galacturonic acids, have been identified.
Lemon bioflavonoid complex is a hygroscopic dried powder of lemon peel extract containing the water-soluble flavonoids and associated complex extractives. It has been reported that the Sunk ist preparation contains about 35% of mono- and disaccharides [chiefly glucose, fructose, and sucrose], 15% ash, 9-12% calcium citrate, 1.5-3.0% citric acid, about 4-7% bioflavonoids and unspec ified amounts of inositol and other organic acids. The most plen tiful flavonoid is hesperidin, with lesser amounts present of eriocitrin, naringen rutino side, diosmin, the 7-rutinosides of luteo lin and apigenin, and rutin. The rutin content of this preparation ranges from 240-640 μg/g with an average of 440 μg/g. No free quercetin was detected. A lemon bioflavonoid complex marketed by another firm was reported to contain an estimated 50% carbo hydrate and 10-15% flavonoids. The flavonoids were not identified.
Lemon bioflavonoid complex concentrates (LBC concentrates): Animal feeding studies have been conducted with two products designated LBC concentrate (2x) and LBC concentrate (6x). LBC concentrate (2x) was prepared by multiple extractions of LBC with isopropanol to preferentially extract flavonoids followed by distil lation of the solvent and vacuum drying the residual syrup. LBC concentrate (6x) was prepared by extraction of flavonoids from LBC with methyl ethyl ketone followed by removal of solvent. No information is available on the composition of the products. The concentration factor (2x or 6x) refers to the measured increase in citrate concentration in the extract which presumably was related to an increase in concentration of flavonoids.

Chemical properties

One of the possible definitions is lemon bioflavonoid complex, which is a hygroscopic dried powder of lemon peel extract, containing the water-soluble flavonoids and associated complex extractives. According to FDA, lemon bioflavonoid complex (lemon peel infusion) is the dried concentrate of water-soluble flavonoids from washed, deoiled (cold pressed), ground lemon peel. Citrus flavonoids consist of the dried concentrate of the water-soluble flavonoids from washed, deoiled, group peel and pulp of oranges, grapefruit and tangerines for use in special dietary foods in amounts up to 600 mg daily

Composition

A typical preparation contains about 35% of mono- and disaccharides (chiefly glucose, fructose and sucrose), 15% ash, 9 to 12% calcium citrate, 1.5 to 3.0% citric acid, about 4 to 7% bioflavonoids and unspecified amounts of inositol and other organic acids. The most abundant flavonoid is hesperidin, with lesser amounts of eriocitrin, naringen, rutinoside, diosmin, the 7-rutinosides of luteolin and apigenin and rutin. The rutin content ranges from 240 to 640 μg/g with an average of 440 μg/g (Burdock, 1997).