Biological and Clinical Sciences Research Journal
ISSN: 2708-2261
DOI: https://doi.org/10.47264/bcsrj0201007
THERAPEUTIC ACTIVITIES
OF GARLIC CONSTITUENT PHYTOCHEMICALS
ASHFAQ F, ALI Q, HAIDER MA, HAFEEZ MM, MALIK A
Institute of
Molecular Biology and Biotechnology, The University of Lahore, Lahore, Pakistan
Corresponding
author: mansoorhafeez140@gmail.com
Abstract
Garlic (Allium
sativum L.) has medicinal value but also an important dietary component for
centuries. It belongs to the family of Liliaceae, which is mostly grown and
found in Ethiopia and Africa. Ethiopian garlic has been mostly used in
traditional medicines. Inhibitory activity of garlic extract has been reported
by various researchers for Lactobacillus
acidophilus, Staphyloccocus aureus, Nocardia asteroids, pseudomonas aeruginosa,
actinomyces viscosus, veillonella alcaligens bacterial strains. The garlic
paste and lime was used for mouth sore, sore throat and also can be used in
toothpaste to prevent dental caries. The present review describes the potential
of garlic phytochemicals for the improvement of the immune system against
diseases in humans.
Keywords: garlic, Allium sativum,
antibacterial, antifungal, herbal medicine
Introduction
It is the one of
the first crop in early 5000 years ago which was domesticated by human. During
1970’s garlic was tested on 10 different species and shows inhibitory
activities against Salmonella, S. Aureus, Mycobacterium and proteus
species. Garlic is an antibacterial as well as anti-fungal agent (Block, 2010; Rivlin, 2001). As allicin is present in garlic which has
its own molecular properties and several therapeutic effects and it is also basically
a defence molecule. Allicin (allyl thiosulfinate) is a thiol-containing protein
which is a fluid like compound present in garlic. Allicin produce smell of
garlic (Agarwal, 1996; Amagase
et al., 2001). Garlic is the most basic spice used in
Indian & Pakistani foods. Basically due to the presence of allicin in
garlic it became effective against gram positive and gram negative bacteria.
Garlic has also the ability to kill streptococci.
It has a pungent odor, also contain sulphur compounds. Fresh crushed garlic is
used as an effective medicinal extract against common pathogenic (Corzo-Martínez et al.,
2007; Flora, 2009). During 1940’s the main purpose of using
herb plants was to used for herbal medicines which are more effective against
several infections and diseases. Garlic is also good for heart and stomach
disease, also for wound and sexually transmitted diseases (Banerjee and Maulik, 2002). It is also good against the anthrax
disease. Garlic also helps to lower down the cholesterol level. The use of
garlic increases the shelf life of food. Garlic is also used in the form of
capsule and powder form. Louis Pasteur first described the antibacterial activities
of garlic juice. Garlic has antibiotic resistance against several bacteria such
as E. coli, Salmonella, Shigella Senterae,
Pseudomonas, etc. The alliinase enzyme turns into allicin (Kim and Kyung, 2003; Urs et al., 1994). These are responsible for the smell of
garlic and garlic has also several antioxidant properties due to antioxidant
properties. Antioxidants good for cancer, it protect cells from free radical
and prevent the damage of cells due to oxidation. Garlic is not only
antibacterial but also has antifungal & antiprotozoal properties (Jansen et al.,
1989; Kim and Kyung, 2003). When garlic is cooked the allicine of
garlic destroys but in case we use raw garlic which is more effective then
cooked garlic. It has anti-inflammatory, hypoglycaemia, also consist of hormone
like effects. Garlic is oldest medicinal
plant used in foods and as a medicine in different ways (Shimon et al.,
2007; Wang et al., 2011).
Chemical properties
Allicin is not
present in fresh garlic clove. It is odourless amino acid, not stable at room
temperature, contains sulphur, is anti-hypertensive, antioxidant, and also has
lipid lowering properties. Diallyl disulfide is organosulfur compound with
light yellowish color. Due to this compound, most bacteria are sensitive to
extracts from plants such as clove, garlic, mustard, onion, organo, turmeric
etc. Garlic can also cause adverse reaction on our health such as allergy, cardiovascular
problem dermartitis and bleeding under controlled manner (Shimon et al.,
2007; Zhou and Wang, 2009). Adverse reactions are due to the improper
use of garlic and poor remedies. Garlic allergy has been manifested as
rhinitis, asthma, anaphylaxis contact dermatitis and pemphigus. Diallyl disulfide
(C6H10S2)
and allylpropyle disulfide (C6H12S2)
are the basic components of garlic which are causative of allergies. Allylpropyl is the strongest sensitizer. Garlic
consisted of anti-mitotic potential against colon neoplassic lesions in vivo
and colon tumour cell growth in vitro. It inhibits colon cancer. It also has
anti obesity properties which directly mean it helps to increase the metabolic
rate and in this way it lower downs the cholesterol level (Banerjee and Maulik, 2002; Shimon
et al., 2007). Further study is needed to ascertain its
toxicity against mammalian cells in vivo
method may be used to confirm its potential side effects and efficacy. According to a survey 77% of the garlic is
produced in India, South Korea, Egypt, Russia, , Myanmar, Ethiopia , USA ,
Bangladesh, & Ukraine ( 1856 MMT ).
Organosulfur is
derived from organic compounds, also present between the hot acidic volcanoes
and deep in sea or ocean. Organosulphure is present in all living cells as the
important amino acids, in the form of cysteine, cystine, and methionine they
are important compounds of proteins (Chakraborty and Hancz, 2011; Tsai
et al., 2012). Organosulfur consist of five cyclic
compounds, isolated from the Allium sativum’s leaves on the basis of
physiochemicals. Organosulphur is mostly present in cruciferous vegetables,
cauliflower, garlic, onion etc (Bayan et al., 2014; Iciek
et al., 2009).
Medical importance
Garlic is a
naturally a good source of therapeutic agents. Garlic is an ethno
pharmaceutical drug but also proved to have therapeutic effects by different
scientific studies allicin an organosulfur compounds, which prevent lipids from
biosynthesis it was proved from a study that it damage the Candida albicans cell
wall and inhibition of RNA in bacteria. For batter results garlic should be
fresh and chemical free. Pure allicin has been found effective against isolates
of Aspergillus in vitro study (Kuettner et al.,
2002; Zhou and Wang, 2009). It is also good for hair growth, for flu
and anti-febrile. Garlic also helps to get rid of intestinal tract of Giardia limbia which is a parasite live water stream and it causes
infection (giardiasis) in small intestine (Harris et al.,
2001; Sallam et al.,
2004). Mostly homeo-pathies refers to take garlic cloves
dissolved in water three times a day to get rid of Giardia. Antimicrobial
activity: as the allicin consist of organosulfur compounds which are the most
important for the antimicrobial property. Anti-helminthic activity: helminthic is basically infection
caused by worm, the body is infectd with parasitic worm. Garlic has been used
to treat the parasitic infections in humans and animals as well (Hughes and Lawson, 1991; Ross
et al., 2001). It has also shown antihelminthic activity
against Ascaris lumbricoldes. Diallyl trisulphide has shown activity against
several protozoans e.g. Trypanosoma
species, Entamoeba bistolytica and giadia lamblia. The
natural phytochemicals are present in it which is more effective alternative to
antibiotics (Avato et al., 2000; Goncagul
and Ayaz, 2010). It has ability to kill all natural
streptococcus strains. Garlic is an immunosuppressive for down regulation of
pro inflammatory responses. It is also reported that in both effects vivo and
vitro the secretion pattern of cytokines from TH2 to TH1 (T helper cell type 2
and 1 ) interferon-gamma and nitric oxide production also under the certain
conditions (Indu et al., 2006; Lai
and Roy, 2004).
Mechanism of action and synergistic effect of garlic
It is studied that
due the complex nature of plants, posses multiple mechanisms of action some of
them are: viability, number of virulence factors, effect of antibiotic as
resistance modifying agent. By the disruption of structure and membrane
function, interruption in synthesis of DNA/RNA take place coagulation of
cytoplasmic constituents occurs. Different agents involve in the interaction
between synergistic effects and they are more efficient than other. There are
several phases of effect active sites of bacterial cell are modified,
degradation of antibiotics, membrane permeability increases, inhibits efflux
pump (Gull et al., 2012; Indu
et al., 2006).
Antioxidant efficacy
Garlic is rich in
antioxidents which help to destroy the free radicals and particles that damage
cell membrane and DNA which slows down the aging process. Garlic has complex
chemical properties which have apparently opposite biological effects and play
role in the antioxidants properties but if it is taken in higher it may cause
toxic effects to heart and liver (Sallam et al.,
2004; Yin and Cheng, 2003).
Antibacterial effect of garlic on dental plaque: dental plaque is the most common cause of
dental disease. Plaque is actually the stick deposit on teeth consist of number
of bacteria together. Plaque is not only bad for teeth but also bad for other
health issues. Plaque removal is most important for the prevention of dental
health and overall health (Chakraborty and Hancz, 2011; Sallam
et al., 2004). Allium
sativum is good alternatives to antibiotics it is effective against Escherichia coli, lactobacilli, klebsiella
pneumonia, pseudomonas aereuginosa, mycobacterium tuberculosis. It
responsive to minimum 4 to 32 ug/ml. Pure extracts are more efficient against
cecalbacteria. It is more effective against Candida
Albicans which is mostly present in
oral cavity. Garlic also acts synergistically with antibiotics (Lai and Roy, 2004; Ross et al., 2001).
Effect of garlic on human stomach: Helicobacter
Pylori is most common
bactreria in human stomach. Garlic has contribution in the treatment of H. pylori infection. H. pylori can cause severe gastritis
which affect fundus, ulcer, malt lymphoma thyroid and skin are the common
diseases or infections caused by H. pylori.
The treatment of H. pylori consists
of a proton pump inhibitor and two antibiotics amoxicillin and clarithyromycine
for at least two weeks. People suffering from gastric disease have secretion of
hydrochloric acid find it hard to tolerate (Flora, 2009; Londhe, 2011; Tsai
et al., 2012). Garlic has been used world widely for
several infections garlic is the best alternative of antibiotics. Several remedies have been discovered for drug
development, these are pure standardize products obtained for herbal medicines.
Secondary metabolites and phytochemicals seem to be the most important for
screening purpose and drug development. Natural products have many advantages
over to synthetic chemical drugs (Calo et al.,
2015; Gyawali
and Ibrahim, 2014).
Garlic for hairs: Garlic consists of vitamin B-6 and C which are good
for hair growth. Garlic is also good for health scalp because of its
antibacterial and antifungal properties and which is also good for dandruff.
Garlic may cause burns on skin when applied on skin (Hajheydari et al.,
2007; Khan et al.,
2008).
For respiratory infections: in Russia garlic is also known as to be used
for respiratory infection treatment by the physicians. It was also used as the
inhalator for children. During World War 1 it was used for the soldier’s
treatment so garlic was named as Russian garlic or a natural antibiotic (Lissiman et al.,
2014).
People use garlic
as a basic spice in their cusine have low risk of blood vessel disease
atherosclerosis and other heart diseases and also lower down the cholesterol (Bongiorno et al.,
2008; Rouf et al.,
2020).
Anti-biofilm activity: Multi drug resistance are the most common concern of
the society nowadays. The anti biotic resistance have been increased the study
based on nano-particles containing garlic extract. Bacterial biofilms are
produced due to the drug resistant bacteria which add more resistance. Staphylococcus aureaus biofilms are
commonly used for anti-bacterial activity studies. The study suggest GE-np are
promising treatment and helpful for chronic infection treatment due to the
presence of biofilm resistance (Girish et al.,
2019; Vijayakumar et al., 2019).
Antiviral activity of garlic: influenza virus is the most common virus
related to respiratory diseases because of its antigenic variations, there are
very complex mutations which make it difficult to make the effective vaccine. Garlic
is the one of most effective herbal against influenza virus (Bilal et al., 2020; Chattopadhyay
and Naik, 2007).
Garlic and covid-19: Garlic fight
against bronchitis infection and basically in corona virus bronchitus infection
is the major symptom. As garlic is good for boosting immune system and also has
several anti-bacterial properties to fight gainstbacteria(Chattopadhyay and Naik, 2007). But covid-19 is a new virus so many
researches did research on garlic but didn’t have any satisfied result, so
garlic can be used for immunity boosting purpose to fight against covid-19 as garlic
is good source for boosting immunity.
Role of garlic in wound healing: Several studies have shown that garlic
extract increase the rate of wound healing also decrease the rate of infection.
Fibrinogen is activated by allicin which is present in garlic and fibrinogen is
most important for wound healing. Garlic
containing ointment has more healing power (Alhashim and Lombardo, 2018; Ejaz
et al., 2009).
Food pathogens sensitivity (garlic): The inhibitory activity of garlic against staphyllococus aureus, E. coli and listeria was measured by the turbidity
method and is used garlic for stomach chills, flatulence, colics etc. Garlic is
basically an inhibitor for food pathogens. Garlic increases the shelf life and
decreases the chances of food poisoning and spoilage (Kuettner et al.,
2002; Tsai et al.,
2012).
Garlic for hypertension: Garlic is widely used for the lowering of blood pressure
due to hypertension number of patients die. The herbal medicine have great
impact on cardiovascular, still some evidences are not clearly identified that
garlic provide a satisfied therapeutic advantage against some diseases. Two
trials were done on 87 patients but not satisfied results found against
hypertension (Gull et al., 2012; Reinhart
et al., 2008).
Prevention of pre-eclampsia from garlic: Pre-eclampsia
is a condition of high blood pressure in which oedema (fluid retention) and
proteinuria (protein in urine) are major symptoms. It affects some women during
second half of the pregnancy or may be after the delivery of their baby, women
kidneys, brain and liver may also be affected and obesity occurs. Low number of
evidence found that garlic is helpful to reduce the pre-eclampsia risk (Meher and Duley, 2006; Thangaratinam
et al., 2011).
Garlic against tuberculosis: Tuberculosis is a kind of bacterial
infection caused by Mycobacterium
tuberculosis. It is globally most faced problem. According to homeopathy
medicine garlic has the resistant properties against tuberculosis. As explained
in various studies that garlic has anti-mycobacterium activities. Mycobacterium tuberculosis is the most
sensitive and rapidly died (Nasiru et al.,
2012; Rao et al., 1946).
Intestinal parasites: In several lab studies researchers suggested that raw
or cooked in both forms garlic is effective against the intestinal parasites
such as roundworm and ascaris lumbricoids (Ankri and Mirelman, 1999; Burke
et al., 2009).
Ear pain and garlic: most children have ear problem they feel ear pain and it’s
called as otitis media. Mostly pain killers are given to the patient but now
according to the latest herbal research it is suggested that ear drops
containing garlic extract are good for pain relief (Ismaiel et al.,
2012; Rose et al.,
1990; Uzun et al.,
2019) .
How to use it effectively: mostly at high temperature the allicin is
killed. So add garlic in your recipes when your cooking is almost done.
Conclusions
It was concluded
from all of our discussions that garlic is an important natural herb which may
be used for improving immune system. It must be used on daily basis for
combating with diseases to live healthy and long life. However, still more
research studies are required to evaluate the potential of garlic as natural
herbal medicine.
Conflict of interest
The authors
declared absence of conflict of interest.
References
Block,
E. (2010). "Garlic other alliums," RSC publishing Cambridge.
Iciek,
M., Kwiecień, I., and Włodek, L. (2009). Biological properties of
garlic and garlic‐derived organosulfur
compounds. Environmental and molecular
mutagenesis 50, 247-265.
Meher,
S., and Duley, L. (2006). Garlic for preventing pre‐eclampsia and its complications. Cochrane Database of Systematic Reviews.