|
Following are abstracts from PubMed addressing Grapefruit Seed Extract.
Apparently, GSE contains a synthetic antibacterial product similar to
Triclosan. This means that although GSE probably does provide some
antibacterial property to your product, it cannot be considered
natural.
|
J Altern Complement Med. 2002 Jun;8(3):333-40.
|
|
Erratum
in:
J
Altern Complement Med 2002 Aug;8(4):521. Reagor Lana [corrected to
Reagor Lee]
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, Cox R,
Zhao JG, Reagor L.
Department of Surgery (Plastic), School of Medicine, University of Texas
Medical Branch, Galveston, USA. jphegger@utmb.edu
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.
PMID:
12165191 [PubMed - indexed for MEDLINE]
 2:
J Altern Complement Med. 2002 Jun;8(3):325-32.
|
|
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.
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.
PMID:
12165190 [PubMed - indexed for MEDLINE]
3:
Pharmazie. 1999 Jun;54(6):452-6.
|
|
Aspects of the antimicrobial efficacy of grapefruit seed extract and its
relation to preservative substances contained.
von
Woedtke T, Schluter B, Pflegel P, Lindequist U, Julich WD.
Institute of Pharmacy, Ernst Moritz Arndt University, Greifswald,
Germany.
The
antimicrobial efficacy as well as the content of preservative agents of
six commercially available grapefruit seed extracts were examined. Five
of the six extracts showed a high growth inhibiting activity against the
test germs Bacillus subtilis SBUG 14, Micrococcus flavus SBUG 16,
Staphylococcus aureus SBUG 11, Serratia marcescens SBUG 9, Escherichia
coli SBUG 17, Proteus mirabilis SBUG 47, and Candida maltosa SBUG 700.
In all of the antimicrobial active grapefruit seed extracts, the
preservative benzethonium chloride was detected by thin layer
chromatography. Additionally, three extracts contained the preserving
substances triclosan and methyl parabene. In only one of the grapefruit
seed extracts tested no preservative agent was found. However, with this
extract as well as with several self-made extracts from seed and
juiceless pulp of grapefruits (Citrus paradisi) no antimicrobial
activity could be detected (standard serial broth dilution assay, agar
diffusion test). Thus, it is concluded that the potent as well as nearly
universal antimicrobial activity being attributed to grapefruit seed
extract is merely due to the synthetic preservative agents contained
within. Natural products with antimicrobial activity do not appear to be
present.
PMID:
10399191 [PubMed - indexed for MEDLINE]
4:
Eisei Shikenjo Hokoku. 1996;(114):38-42.
|
|
[Analysis of components in natural food additive "grapefruit seed
extract" by HPLC and LC/MS]
[Article in Japanese]
Sakamoto S, Sato K, Maitani T, Yamada T.
The
components in a commercial natural food additive "Grapefruit seed
extract" and the ethanol extract of grapefruit seeds were analyzed by
HPLC and LC/MS. The HPLC chromatogram of the commercial grapefruit seed
extract was quite different from that of the ethanol extract of
grapefruit seeds. Three main peaks were observed in the chromatogram of
the commercial grapefruit seed extract. By comparison of the retention
times and the absorption spectra with those of authentic samples, two
peaks were ascribed to methyl-p-hydroxybenzoate and
2,4,4'-trichloro-2'-hydroxydiphenylether (triclosan). Triclosan was also
identified by LC/MS by using the negative electrospray ionization
method.
PMID:
9037863 [PubMed - indexed for MEDLINE]
|
J Agric Food Chem. 2001 Jul;49(7):3316-20.
|
|
Identification of benzethonium chloride in commercial grapefruit seed
extracts.
Takeoka G, Dao L, Wong RY, Lundin R, Mahoney N.
Western
Regional Research Center, Agricultural Research Service, U.S. Department
of Agriculture, 800 Buchanan Street, Albany, California 94710, USA. grt@pw.usda.gov
Commercial grapefruit seed extracts (GSE) were extracted with
chloroform. The solvent was evaporated, and the resulting solid was
subsequently analyzed by high-performance liquid chromatography,
electrospray ionization mass spectrometry, nuclear magnetic resonance (NMR)
spectroscopy, and elemental analysis (by proton-induced X-ray emission [PIXE]
analysis). The main constituent was identified as benzethonium chloride,
a synthetic antimicrobial agent commonly used in cosmetics and other
topical applications. This compound comprised 8.03% (n = 2) of the
liquid GSE sample. Higher amounts of benzethonium chloride were found in
powder GSE samples.
PMID:
11453769 [PubMed - indexed for MEDLINE]
2:
Toxicology. 2000 Apr 3;144(1-3):107-11.
|
|
Environmental inhibition of 11beta-hydroxysteroid dehydrogenase.
Reidenberg MM.
Department of Pharmacology/Box 70/Room LC 428, Weill Medical College,
1300 York Avenue, New York, NY 10021, USA. mmreid@mail.med.cornell.edu
Gossypol, a polyphenolic compound from cotton seed, caused hypokalemia
in some men receiving it in a trial of its contraceptive activity.
Searching for the mechanism for its hypokalemic action led to the
observation that it inhibited 11beta-hydroxysteroid dehydrogenase. This
would enhance mineralocorticoid effect in the kidney. Many other
polyphenols also inhibit this enzyme including those in grapefruit
juice. Ingesting 1-2 l of grapefruit juice inhibited this enzyme in two
men in a clinical experiment. Tea polyphenols inhibit this enzyme and
add to the inhibition caused by gossypol. Men in China have lower serum
potassium values than men elsewhere and this is due to the environment,
presumably the diet, in China. The importance of dietary and other
exogenous inhibitors of this enzyme in electrolyte metabolism remains to
be determined.
Publication Types:
Review
Review, Tutorial
PMID: 10781877 [PubMed - indexed for MEDLINE]
3:
Crit Rev Food Sci Nutr. 1983;19(1):1-98.
|
|
Citrus fruits. Part II. Chemistry, technology, and quality evaluation.
B. Technology.
Ranganna S, Govindarajan VS, Ramana KV.
In Part
II of this review on citrus fruits, the literature on chemistry,
technology, and quality evaluation are critically considered. Sweet
oranges, mandarin, grapefruit, lemon, and lime are generally used for
processing. The literature on chemical components of citrus fruit which
include sugars, polysaccharides, organic acids, nitrogenous constituents
and lipids; carotenoids which contribute to color; vitamins and minerals
and flavonoids; limonoids, some of which impart bitterness to the juice;
and the volatile components which contribute to aroma were reviewed in
section A. Chilled and pasteurized juices, juice concentrates, and
beverages are the important products manufactured commercially, and to a
limited extent powdered citrus juices, canned segments, and marmalades.
The literature on the manufacture of these products also as new types of
juice and oil extractors; TASTE and other types of evaporators; tank
farms to store juice and concentrate in bulk; aseptic filling in bulk
containers and retail packs; alternate flexible and rigid containers
other than glass and tin; and recovery of volatile flavoring
constituents during juice processing are some of the important
technological developments in the recent past and have been discussed in
this section. Bitterness in citrus juices and its control, composition
of cloud, and its stability and changes during storage have been
reviewed. Essential oils, pectin, frozen and dried juice sacs, dried
pulp and molasses, flavonoids, seed oil, and meal are the important
byproducts, the manufacture of which is given in essential details.
Generally, consumers judge the product on the basis of its sensory
attributes. The quality of finished product is dependent upon the raw
materials used and control of processes. In section C, the U.S.
Department of Agriculture (USDA) standards for different products,
physicochemical and microbiological parameters prescribed as indices of
quality of fruit, juice, concentrate, and other products; composition of
essential oils; and aroma concentrates are discussed in relation to
sensory quality. Analytical methods for compounds affecting quality, and
methods for detection of adulteration in different citrus products are
briefly reviewed. The importance of sensorily evaluating quality of
citrus products to select and develop quality control indices is
emphasized. Areas where further research are required are indicated. A
comprehensive bibliography is provided to aid further study and
research.
Publication Types:
Review
PMID:
6380950 [PubMed - indexed for MEDLINE]
4:
Crit Rev Food Sci Nutr. 1983;18(4):313-86.
|
|
Citrus fruits--varieties, chemistry, technology, and quality evaluation.
Part II. Chemistry, technology, and quality evaluation. A. Chemistry.
Ranganna S, Govindarajan VS, Ramana KV.
In Part
2 of this review on citrus fruits, the literature on chemistry,
technology, and quality evaluation are critically considered. Sweet
oranges, mandarin, grapefruit, lemon, and lime are generally used for
processing. The literature on chemical components of citrus fruit which
include sugars, polysaccharides, oraganic acids, nitrogenous
constituents and lipids; carotenoids which contribute to color; vitamins
and minerals, and flavonoids; limonoids, some of which impart bitterness
to the juice; and the volatile components which contribute to aroma have
been reviewed. Chilled and pasteurized juices, juice concentrates, and
beverages are the important products manufactured commercially, and to a
limited extent powdered citrus juices, canned segments, and marmalades.
The literature on the manufacture of these products also as new types of
juice and oil extractors; TASTE and other types of evaporators; tank
farms to store juice and concentrate in bulk; aseptic filling in bulk
containers and retail packs; alternate flexible and rigid containers
other than glass and tin; and recovery of volatile flavoring
constituents during juice processing are some of the important
technological developments in the recent past and have been discussed.
Bitterness in citrus juices and its control, composition of cloud, and
its stability and changes during storage have been reviewed. Essential
oils, pectin, frozen and dried juice sacs, dried pulp and molasses,
flavonoids, seed oil, and meal are the important byproducts, the
manufacture of which is given in essential details. Generally, consumers
judge the product on the basis of its sensory attributes. The quality of
finished product is dependent upon the raw materials used and control of
processes. The U.S. Department of Agriculture (USDA) standards for
different products, physicochemical and microbiological parameters
prescribed as indices of quality of fruit, juice, concentrate, and other
products; composition of essential oils; and aroma concentrates are
discussed in relation to sensory quality. Analytical methods for
compounds affecting quality, and methods for detection of adulteration
in different citrus products are briefly reviewed. The importance of
sensorily evaluating quality of citrus products to select and develop
quality control indices is emphasized. Areas where further research are
required are indicated. A comprehensive bibliography is provided to aid
further study and research.
Publication Types:
Review
PMID:
6354594 [PubMed - indexed for MEDLINE]
|
Burns. 2004 Dec;30(8):772-7.
|
|
The
effect of essential oils on methicillin-resistant Staphylococcus aureus
using a dressing model.
Edwards-Jones V, Buck R, Shawcross SG, Dawson MM, Dunn K.
Department of Biological Sciences, the Manchester Metropolitan
University, Chester Street, Manchester, M15GD, UK. v.e.jones@mmu.ac.uk
Patchouli, tea tree, geranium, lavender essential oils and Citricidal
(grapefruit seed extract) were used singly and in combination to assess
their anti-bacterial activity against three strains of Staphylococcus
aureus: Oxford S. aureus NCTC 6571 (Oxford strain), Epidemic methicillin-resistant
S. aureus (EMRSA 15) and MRSA (untypable). The individual essential
oils, extracts and combinations were impregnated into filter paper discs
and placed on the surface of agar plates, pre-seeded with the
appropriate strain of Staphylococcus. The effects of the vapours of the
oils and oil combinations were also assessed using impregnated filter
paper discs that were placed on the underside of the Petri dish lid at a
distance of 8mm from the bacteria. The most inhibitory combinations of
oils for each strain were used in a dressing model constructed using a
four layers of dressings: the primary layer consisted of either Jelonet
or TelfaClear with or without Flamazine; the second was a layer of
gauze, the third a layer of Gamgee and the final layer was Crepe
bandage. The oil combinations were placed in either the gauze or the
Gamgee layer. This four-layered dressing was placed over the seeded agar
plate, incubated for 24h at 37 degrees C and the zones of inhibition
measured. All experiments were repeated on three separate occasions. No
anti-bacterial effects were observed when Flamazine was smeared on the
gauze in the dressing model. When Telfaclear was used as the primary
layer in the dressing model compared to Jelonet, greater zones of
inhibition were observed. A combination of Citricidal and geranium oil
showed the greatest-anti-bacterial effects against MRSA, whilst a
combination of geranium and tea tree oil was most active against the
methicillin-sensitive S. aureus (Oxford strain). This study demonstrates
the potential of essential oils and essential oil vapours as
antibacterial agents and for use in the treatment of MRSA infection.
|
J Altern Complement Med. 2002 Jun;8(3):325-32.
|
|
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.
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.
Other
Websites that address this issue:
On the
following site, you will find this quote: "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) similar to benzethonium chloride when
analyzed 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) "
Even on
this pro-Citricidal site, they explain a little about the synthesis of
the Triclosan-like preservative, while still claiming it to be natural.
|
