A Comparison Of The Antimicrobial (Antifungal) Properties Of Garlic, Ginger And Lime On Aspergillus Flavus, Aspergillus Niger And Cladosporium Herbarum Using Organic And Water Base Extraction Methods
D Tagoe, S Baidoo, I Dadzie, V Kangah, H Nyarko
D Tagoe, S Baidoo, I Dadzie, V Kangah, H Nyarko. A Comparison Of The Antimicrobial (Antifungal) Properties Of Garlic, Ginger And Lime On Aspergillus Flavus, Aspergillus Niger And Cladosporium Herbarum Using Organic And Water Base Extraction Methods. The Internet Journal of Tropical Medicine. 2009 Volume 7 Number 1.
The study aim at comparing the antimicrobial (antifungal) properties of garlic, ginger and lime on
The use of plant parts as a source of medicine to treat infectious diseases predates history as a result of which nearly all cultures and civilizations from ancient times to the present day have used herbal medicines to cure infections1. Ethno-pharmacological use of plants prevails among most African countries where plants are used in treating malaria, diarrhoea, burns, gonorrhoea, stomach disorders and other infectious diseases2. These plants which are easily available and cheaper than the conventional drugs include garlic, ginger and lime fruit which in their natural state are widely used in West Africa as herbal medicines3. A report from the World Health Organisation revealed that 80% of the world’s population relies on traditional therapies which involve the use of plants extracts or their active substances4 whilst actively encouraging national governments of member countries to utilize their traditional systems of medicines with regulations suitable to their national health care systems5. Extraction refers to processes for the isolation of the active ingredients from drug material and this may be by physical means or by dissolving in a suitable menstruum (liquid solvent e.g. water or alcohol)6. The extracts (antimicrobial agents) when isolated are contained in the phytochemical constituents (Alkaloids, Saponins, Tannins etc.) of the plants7. Over the years much effort has been devoted to the search for new antimicrobial (antifungal) agents from natural sources such as plants and others for treatments and for food preservation 3, 8-13.
The antimicrobial activities of such plant extracts have been linked to the presence of bioactive compounds which sometimes serve to protect the plants themselves against bacteria, fungi and viral infections as well as exhibiting their antimicrobial properties on these organisms14. Allicin in garlic extracts have been found to be effective as an antifungal, antibacterial, antiviral and anti-parasitic agent15. Ginger contains the compound caprylic acid, which has potent antifungal properties and is popularly used to treat conditions like indigestion, nausea, vomiting, sore throats, the common cold, headache, fevers, flu symptoms, rheumatism, and motion sickness16. Lime is also an essential ingredient in the preparation of most herbal concoction which is sometimes used to suppress stomach ache and possess antimicrobial activities in conjunction with other extracts3.
Materials and Methods
Materials, Laboratory Location and Period of Research
The research material ginger, onion and garlic were obtained from Pedu Market in the Cape Coast Metropolis of Ghana whilst laboratory activity was undertaken at the Laboratories of Department of Laboratory Technology and Molecular and Biotechnology of the University of Cape Coast, in Cape Coast, Ghana between December, 2009 to May, 2010.
Plant Extraction: 100g of cleaned, air dried plant extracts of ginger, garlic and lime obtained were blended separately and individually soaked in 100mls of ethanol for 24hrs in a sterile glass container. The pulp obtained was shaken vigorously to allow for proper extraction of active ingredients. The crude extract was then filtered using sterile Whatmans No. 1 filter paper. The filtered extracts were then stored in the refrigerator at 40C. The process was repeated using sterile distilled water as the extractive medium.
Fungal isolation: Test fungi (
Antifungal Screening Test: Six each of washed, dried and sterilized plates were labeled for each ethanol base plant extracts with two each of the six labeled for each fungi. Six plates were also labeled as positive controls using ethanol only with two plates each corresponding to each test fungi. A further six plates were labeled as negative controls without any antimicrobial agent (plant extract) nor ethanol with two plates corresponding to each test fungi. This makes a total of thirty (30) plates for ethanol extract medium sensitivity testing. 1ml of ethanol base plant extract was dispensed using separate sterilized micropipettes into each extract labeled Petri dish. 1ml of ethanol only was dispensed using another sterile micropipette into ethanol only labeled Petri dishes. Sterilized molten Potato Dextrose Agar (PDA) cooled at 45 ºC was dispensed separately into each of the plates including the plates without plant extract and ethanol. Each plate was swirled gently in a clockwise and anti-clockwise motion to mix the extracts with the PDA and allowed to solidify. A streak of the pure cultures of the test fungi were then transferred unto the Petri dishes containing the PDA and the plant extract using a sterile inoculation needle. The plates were covered and incubated at room temperature at 28±3 ºC for two days after which diameter growth of the test fungi were measured horizontally, vertically and diagonally and mean values calculated. Measurement of diameter was made at daily intervals for six days. The above procedure was repeated for water base plant extraction using distilled water only as the positive control and PDA only without plant extract and water as the negative control. Incubation and measurement were undertaken as described above.
Statistical analysis: Data obtained in the study were descriptively analyzed using Statview from SAS version 5 and the means separated using double-tailed Paired Means Comparison. Microsoft Excel was used in plotting the graphs.
In organic ethanolic extraction, results from the study showed that lime had the greatest inhibition of diameter growth on
With inorganic water base extraction medium, Garlic had the greatest inhibition in diameter growth (0.934cm), followed by lime (1.150cm) on
The phytochemical constituents of medicinal plants such as garlic, ginger, lime, onion etc have longed been known and their antimicrobial properties have been widely studied and reported22-23.
In the ethanol base extraction medium, all three ethanolic extracts of garlic, ginger and lime significantly inhibited growth of
In the water base extraction medium, there was a marked significant difference in inhibition of
Finally, it could be observed that both ethanolic and water extract of garlic exhibited marked growth inhibiting of all the test fungi (
The significant growth inhibitions of the test fungi by the plant extracts suggest their possible use in controlling these fungi in disease causing situations and food spoilage. Furthermore, the easy means of obtaining these extracts especially using water base extraction provides an alternative to antibiotics and artificial preservatives both of which can be toxic at certain concentrations.
All three medicinal plant extracts exhibited high but varied antifungal activity and can be used in controlling infection, preventing cold meat spoilage and preserve meat for longer periods against fungal contamination. Different extractive techniques correspond to different antimicrobial (antifungal) effectiveness. However, ethanol and water base extraction of garlic produces similarly strong antifungal activity against all test fungi.
We thank the technical staff of the Department of Laboratory Technology and Molecular Biology and Biotechnology.