Properties of ginger:
South of Asia. Cultivated in many warm places.
Ginger or ginger root is the rhizome of the plant Zingiber officinale, consumed as a delicacy, medicine, or spice. It lends its name to its genus and family (Zingiberaceae). Other notable members of this plant family are turmeric, cardamom, and galangal.
Components and chemistry:
The characteristic odor and flavor of ginger is caused by a mixture of nonvolatile phenylpropanoid-derived compounds, particularly zingerone , shogaols and gingerols , volatile oils that compose one to three percent of the weight of fresh ginger.
Medicinal use and research
According to the American Cancer Society, ginger has been promoted as a cancer treatment "to keep tumors from developing", but "available scientific evidence does not support this". In limited studies, ginger was found to be more effective than placebo for treating nausea caused by seasickness, morning sickness and chemotherapy, although ginger was not found superior to placebo for pre-emptively treating post-operative nausea. Some studies advise against taking ginger during pregnancy, suggesting that ginger is mutagenic, though some other studies have reported antimutagenic effects. Other preliminary studies showed that ginger may affect arthritis pain or have blood thinning and cholesterol lowering properties, but these effects remain unconfirmed
Ginger has a sialagogue action, stimulating the production of saliva, which makes swallowing easier.
In laboratory animals, the gingerols increase the motility of the gastrointestinal tract and have analgesic, sedative and antipyretic.
Moreover, it is proved that ginger has an antibacterial activity and that the inhibition of bacterial growth was dose dependent and this is going to be the topic of our work.
MATERIAL AND METHODS
Collection and treatment of sample
The ginger roots were sun dried for seven days and ground into fine powder using an electric grinder. Then 100g of the powdered mass obtained was stored in clean sterile bottles at room temperature and used for the extractions.
The soxhlet ethanolic extracts was obtained by soxhlet extraction of 20g of ginger powder in 100ml of 95% ethanol at 78°C using soxhlet apparatus. The extract was then concentrated to 20ml on a water bath and dried at room temperature.
The n-hexane extract was obtained by dissolving 20g of the powdered ginger in 100ml of n-hexane in a conical flask. The mixture was stirred, covered, and allowed to stand for 24hrs, and filtered using sterile Whitman No.1 filter paper. The filtrate was concentrated to 20ml on a water bath and evaporated to dryness at room temperature.
The ethyl acetate and water extracts were obtained by repeating the above procedure for nhexane. The various extracts were used for the analysis of antibacterial activities and bacterial inhibition assay.
Preparation of the nutrient medium
Nutrient agar medium was prepared by dissolving 2.8g of nutrient agar in 100ml distilled water. The solution was sterilized in an autoclave at 121°C (1.1N pressure) for 15 min. The suspension was cooled and poured into sterile Petri-dishes to solidify. The agar depth of the medium was 4.0mm.
Antibacterial activity and medicinal properties of ginger
Ginger extract and Pseudomonas Aeruginosa
Ginger (Zingiber officinale) extract was prepared from 150 g ginger root shredded with 300 mL toluene (99.9%) using a standard kitchen blender. After shredding, debris was allowed to settle for 24 h at room temperature. Then it was filtered through filter paper (pore size = 11μm) and was added 150 mL deionized water. The filtrate (100% ginger extract) was used to test whether or not ginger extract inhibits biofilm formation.
To evaluate the effect of ginger extract on the growth of Pseudomonas Aeruginosa , grown in batch cultures with ginger extract (1 and 10% each) and without. The cultures demonstrated typical bacterial growth curves including lag, exponential, and stationary phases during 14 h of incubation. In addition, no significant differences in the growth curve occurred between the cultures with ginger extract (1 and 10%) and without. The results suggested that the growth of PA14 was unaffected by the addition of ginger extract up to 10%.
Static biofilm quantification assay was performed to evaluate the effect of ginger extract on PA14 biofilm formation. The figure below shows the difference in biofilm formation between the control (i.e., no ginger extract addition) and the culture containing ginger extract (1, 5, and 10% each). The microtiter plates showed that biofilm formation for the experimental group (i.e. cultures with ginger extract) was 39–56% less than the amount of formation in the control (i.e. without ginger extract). The differences in biofilm reduction for ginger extract concentration (P > 0.5) and for incubation time were not significant (P > 0.1). The results suggested that the biofilm formation of PA14 is inhibited by the addition of ginger extract in microtiter plates. The inhibition of biofilm formation by ginger extract was not due to minor contamination with toluene or something extracted from the plastic/glassware during the preparation of ginger extract, which was confirmed by an experiment using mock extraction.
In conclusion, this study clearly demonstrated the effectiveness of ginger extract in inhibiting PA14 biofilm formation. Ginger extract reduced cellular c-di-GMP concentration, which appears to affect characteristic phenotypes as demonstrated by reduced biofilm formation. The results are a baseline for researching the ginger compounds involved in c-di-GMP reduction and for identifying the c-di-GMP regulation mechanisms of these compounds.
Ginger Extract Inhibits Biofilm Formation by Pseudomonas aeruginosa PA14
Ginger extract and Porphyromonas and Prevotella
Porphyromonas and Prevotella species are obligate anaerobic Gram-negative bacteria and principal oral pathogens in a variety of periodontitis types, since they produce several endodontopathogenic materials. Their products suppress host defense mechanisms and destroy periodontal tissues, leading to the loss of alveolar bones and teeth in the pathogenesis of human periodontitis.
In the present study, the ethanol and n-hexane extracts were found to possess antibacterial properties (MIC: 50 μg/mL) against three black-pigmented periodontal anaerobes (Table 1).
There were obtained five ginger constituents:
*10-gingerol (white crystalline needles, 27 mg)
*12-gingerol (white crystalline needles, 14 mg)
*5-acetoxy-6-gingerol (yellow oil, 6 mg)
*3,5 -diacetoxy-6-gingerdiol (yellow oil, 8 mg)
*galanolactone (white crystalline needles, 8 mg)
By antibacterial evaluation of the purified compounds, -gingerol and -gingerol were found to be effective, but the other compounds exerted no antibacterial effects. The most active, -gingerol, could not only inhibit the growth of the tested oral pathogens at a MIC range of 6–14 μg/mL, but also exhibited bactericidal activity at a MBC range of 4–14 μg/mL.
Likewise, while the galanolactone, is known to be antimicrobial against several Candida species, it was ineffective against the periodontal oral bacteria.
In summary, it was found that -gingerol and -gingerol from the ginger rhizome evidenced potent antibacterial activities in vitro against anaerobic bacteria associated with periodontitis of the human oral cavity by activity-guided assays.
Antibacterial Activity of -Gingerol and -Gingerol isolated from Ginger Rhizome Against Periodontal Bacteria
Ginger extract and Streptococcus mutans, Candida Albicans and Enterococcus Faecalis
Streptococcus mutans (causative organism for dental caries), Candida albicans (causative organisms for candidiasis), and Enterococcus faecalis (causative agent for secondary root canal infection) have been considered very difficult to control as they have developed tolerance against various antimicrobial agents in routine use. This calls for an urgent need to explore novel bio-active compounds, which are safer and biodegradable.
In the present study:
• 10% ethanolic ginger extract showed antimicrobial activity against S. mutans exhibiting maximum zone of inhibition of 8 mm at 75 μl and MIC at 1.25% concentration.
• 10% ethanolic ginger extract showed antimicrobial activity against C. albicans exhibiting maximum zone of inhibition of 11 mm at 75 μl and MIC at 2.5% concentration.
• 10% ethanolic ginger extract showed antimicrobial activity against E. faecalis exhibiting maximum zone of inhibition of 14 mm at 75 μl and MIC at 2.5% concentration.
Assessment of antimicrobial potential of 10% ginger extract against Streptococcus mutans, Candida albicans, and Enterococcus faecalis An in vitro study