Citricidal(r)

[Guest guest]

Below are abstracts of two interesting articles that appeared in the

June 2002 issue of the Journal of Alternative and Complementary

Medicine (New York, N.Y.)

A new list member, " MarthaE " , brought these

two artcles to my attention and asked for my comments:

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The effectiveness of processed grapefruit-seed extract as an

antibacterial agent: I. An in vitro agar assay.

Reagor L, Gusman J, McCoy L, Carino E, Heggers JP.

J Altern Complement Med. 2002 Jun;8(3):325-32.

School of Medicine, University of Texas, Medical Branch, Galveston,

USA.

OBJECTIVES: Grapefruit-seed extract (GSE) Citricidal has, in recent

reports, been reported to be successful in combating a variety of

common infectious agents. In our study, drops of concentrated

grapefruit-seed extract were tested for antibacterial properties

against a number of gram-positive and gram-negative organisms.

DESIGN: Sixty-seven (67) distinct biotypes were tested for their

susceptibilities to the GSE as well as to 5 other topical

antibacterials (Silvadene, Sulfamylon, Bactroban, Nitrofurazone, and

Silvadene, Nystatin). Wells were punched into Mueller-Hinton agar

plates, which were then inoculated with the organism to be tested; each

well was then inoculated with one of the antibacterial agents. After an

overnight incubation period, the plates were checked for zones of

bacterial susceptibility around the individual wells, with a measured

susceptibility zone diameter of 10 mm or more considered a positive

result.

RESULTS: The GSE was consistently antibacterial against all of the

biotypes tested, with susceptibility zone diameters equal to or greater

than 15 mm in each case.

CONCLUSIONS: Our preliminary data thus suggest an antibacterial

characteristic to GSE that is comparable to that of proven topical

antibacterials. Although the GSE appeared to have a somewhat greater

inhibitory effect on gram-positive organisms than on gram-negative

organisms, its comparative effectiveness against a wide range of

bacterial biotypes is significant.

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The effectiveness of processed grapefruit-seed extract as an

antibacterial agent: II. Mechanism of action and in vitro toxicity.

Heggers JP, Cottingham J, Gusman J, Reagor L, McCoy L, Carino E, R,

Zhao JG.

J Altern Complement Med. 2002 Jun;8(3):333-40.

Department of Surgery (Plastic), School of Medicine, University of

Texas Medical Branch, Galveston, USA. jphegger@...

OBJECTIVES: Recent testimonials report grapefruit-seed extract, or GSE

(Citricidal) to be effective against more than 800 bacterial and viral

strains, 100 strains of fungus, and a large number of single and

multicelled parasites. This study investigated GSE for antibacterial

activity at varying time intervals and concentration levels and tissue

toxicity at varying concentrations in an effort to determine if a

concentration existed that was both microbicidal and nontoxic and in

what period of time.

DESIGN: Gram-negative and gram-positive isolates were introduced into

graduated dilutions of GSE (twofold concentrations ranging from 1:1,

through 1:512) for determination of bacterial activity. In vitro assays

with human skin fibroblast cells were also performed at the same

dilutions to determine toxicity.

RESULTS: These tests indicated that from the 1:1 through the 1:128

concentrations, GSE remained toxic as well as bactericidal. However,

test results indicated that at the 1:512 dilution, GSE remained

bactericidal, but completely nontoxic.

CONCLUSIONS: The initial data shows GSE to have antimicrobial

properties against a wide range of gram-negative and gram-positive

organisms at dilutions found to be safe. With the aid of scanning

transmission electron microscopy (STEM), the mechanism of GSE's

antibacterial activity was revealed. It was evident that GSE disrupts

the bacterial membrane and liberates the cytoplasmic contents within 15

minutes after contact even at more dilute concentrations.

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Based on the limited data available on the Citricidal websites, I've

always felt that Citricidal had some " antimicrobial activity " and these

two articles that were published in the Journal of Alternative and

Complementary Medicine only provide more support.

However, just because a raw material or ingredient has antimicrobial

activity does not mean that same item is an effective preservative for

cosmetics. Methylparaben has antimicrobial activity but Methylparaben,

by itself, is not an effective preservative for cosmetics.

And so too, just because Citricidal has demonstrated antimicrobial

activity against some undefined microorganisms does not mean that

Citricidal, by itself, is an effective preservative.

Methylparaben is used as just one component in many multi-component

preservative systems. Perhaps, Citricidal could be used as just one

component of a multi-component preservative system.

In your quest for a natural preservatives system, one of the most

difficult jobs will be defining what is mean by the word " natural " .

I don't believe Citricidal, by itself, is an effective cosmetic

preservative nor does it fit my personal definition of the term

" natural " .

Here's some information on the chemistry and manufacture of Citricidal:

" Citricidal is synthesized from the polyphenolic compounds found in

grapefruit seed and pulp. Numerous reactions are involved, including

distillation, catalytic conversion, and ammoniation. The active

component of Citricidal is a quaternary ammonium chloride(a diphenol

hydroxybenzene reacted with ammonium chloride) similiar to benzethonium

chloride when analysed in accordance with USP XXII/NF XVII. (Benz.

Chloride is a powerful germical agent, but is highly toxic to all

animal life. See info on toxicity, below) "

http://www.nutriteam.com/gfex/citricidal.htm

And at:

http://www.nutriteam.com/gsewhat.html

we have " Grapefruit Extract: What is It?

Grapefruit Extract(GSE) is made by first converting grapefruit seeds

and pulp into a very acidic liquid.

This liquid is loaded with polyphenolic compounds, including quercitin,

helperidin, campherol glycoside, neohelperidin, naringin, apigenin,

rutinoside, poncirin, etc. The polyphenols themselves are unstable but

are chemically converted into more stable substances that belong to a

diverse class of products called quaternary ammonium compounds.

Some quaternary compounds, benzethonium chloride and benzalkonium

chloride, for example, are used industrially as antimicrobials, but are

toxic to animal life. The B vitamin choline is also a quaternary

compound, but is non-toxic and even essential for maintaining healthy

neurological function and fat metabolism.

GSE features the best of both worlds: the quaternary compounds derived

from grapefruit exhibit broad-spectrum antimicrobial activity, while

evidencing none of the toxic side-effects of chemically-derived

quaternaries.

The finished product is a viscous, yellow-amber colored liquid that

features a taste that is both bitter and acidic. (Practitioners of

Chinese and Ayurvedic medicine consider both qualities to be part of

the therapeutic process.) Pure vegetable glycerin is added to reduce

the bitterness and acidity to a tolerable level and to reduce the

possibility that incidental contact could cause irritation to the skin

or mucous membranes.

Grapefruit Extract Production

1) Grapefruit pulp and seeds(the by-product of expeller-extracted

grapefruit juice) is dried and ground into a fine powder.

2) The grapefruit powder is dissolved in purified water and

distilled to remove the fiber and pectin.

3) This distilled slurry is spray dried at low temperatures forming

a concentrated grapefruit bioflavonoid powder.

4) This concentrated powder is dissolved in vegetable glycerine and

heated.

5) Food grade ammonium chloride and ascorbic acid are added, and

this mixture is heated under pressure.

6) This material undergoes catalytic conversion using natural

catalysts (including hydrochloric acid and natural enzymes.).

7) This slurry is cooled, filtered and treated with ultraviolet

light.

The amount of Ammonium Chloride remaining in the final product is

between 15% and 19%.

The amount of Ascorbic Acid remaining in the final product is between

25mg/g and 30mg/g.

There is no residue of hydrochloric acid in the final product. "

Although Citricidal's INCI name is Citrus Grandis (Grapefruit) Fruit

Extract, I wouldn't consider Citricidal natural.

BTW, based on the information provided, Citricidal appears to be an

undefined blend of quaternary ammonium compounds. Therefore, the

antimicrobial activity of Citricidal would be neutralized in anionic

systems.

Maurice

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Maurice O. Hevey

Convergent Cosmetics, Inc.

http://www.ConvergentCosmetics.com

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