A medicinal plant is any plant which contains substances that can be used for therapeutic purpose of which are precursors for the synthesis of useful drugs. The Phytochemical screening of A. sativum extract in this study revealed the presence of phenols, alkaloids, flavonoids, glycosides, saponins, volatile oil, cardiac glycosides, phlobatannins, and steroids. The presence of some of these bioactive components confirms with similar research (Dahiru et al., 2006). The presence of alkaloids, flavonoids, saponin, and cardiac glycosides is in agreement with the work done by other researchers (Idowu et al., 2008). These classes of compounds especially alkaloids, saponins and flavonoids are known to have curative activity against several pathogens (Usman et al., 2009). Saponins are produced by plants to fight against infections by parasites and in humans it helps the immune system and also protect against viruses and bacteria. It has been found out that saponins possess cholesterol lowering, cytotoxic permeabilization of the intestine and also exhibit structure dependent biological activities (Osagie and Eka, 1998).
Flavonoids are water soluble polyphenolic molecules which in together with carotenes are also responsible for the coloring of fruits, vegetables and herbs. Some flavonoid containing plants have antimicrobial properties (Trease and Evans, 2002). Flavonoids detected in A. sativum bulbs could be used for the treatment of various disease conditions like edema, toothache, fever, common cold, diarrhea and dental caries. These could be possible as the root extracts contains some antibacterial activities. The flavonoids act on bacteria by inhibiting its protein synthesis (Hong-xi and Song, 2001).
The morbidity and mortality due to microbial diseases have drastically decreased after the development of effective and safe drugs to deal with bacterial infections. Unfortunately, the emergence of drug-resistant organisms has become a serious threat.
The present study has demonstrated that A. sativum juice extract effectively inhibited the growth of both Pseudomonas sp and S. aureus though their sensitivity to the extract varied based on the presence or absence of skin and the different solvents used for extraction. The MIC values were found to be in the range of 1 to 10 mg/ml in case of Pseudomonas sp and 1 to 100 mg/ml in the case of S. aureus (Graph 16 and 17).
In previous studies, it has been reported that a component named allicin that is present in A. sativum exhibits its antimicrobial activity mainly by immediate and total inhibition of RNA synthesis, although DNA and protein syntheses are also partially inhibited, suggesting that RNA is the primary target of allicin action (Feldberg et al., 1988). The structural differences of the bacterial strains may also play a role in the bacterial susceptibility to A. sativum constituents.
The present study showed that A. sativum extracts also have antifungal activity which is in accordance with Davis et al., 2003. It is clear that A. sativum juice may be useful as an antimicrobial agent against the E. coli, K. pneumoniae, P. mirabilis, P. aeruginosa, and S. aureus (Yadav et al., 2015). The present study suggests that A. sativum is active against organisms that cause wound infection. It has been previously reported that A. sativum is active against organisms that are found to be resistant to conventional antibiotics (Jezowa et al., 1966; Li et al., 2015). Moreover, studies also indicate that combination of A. sativum extracts with conventional antimicrobials leads to partial or total synergism (Didry et al., 1992; Gaekwad and Trivedi, 2013)
The susceptibility of some bacterial strains to the extract A. sativum may be a pointer to its potential as a drug that can be used against these susceptible bacterial strains. Furthermore, the search for alternative drugs or natural antibacterial remedies is important due to antibacterial resistance, especially, among Gram-negative bacteria (Khosravi and Behzadi, 2006).
The antibacterial activity of aqueous, ethanolic and methanolic extracts of A. sativum was determined using Pseudomonas sp and S. aureus. From the result of the zone of inhibition in the microbial study, it was seen that all the extracts demonstrated antibacterial activity. The aqueous extract demonstrated the higher activity followed by ethanolic and methanol extracts.
Findings from this work reveal that FCU doesn’t show any antimicrobial activity. Also the combination of A. sativum juice with FCU didn’t show any synergistic effect. This study also reveals that A. sativum had both antibacterial and antifungal activity. This indicates that the extracts could also be used in the treatment of some wound infections caused by gram negative and gram positive bacteria.
Further research should be conducted to impregnate the bandages with active compounds of A. sativum and analyze whether it is active against infections in a real wound setting.
The phytochemical screening and investigation into the antibacterial potential of the extract of A. sativum showed or highlighted the antibiotic spectra of the A. sativum extract under assay, suggesting a promising lead as an alternative antibiotic and it yielded scientific support to their use in traditional ayurvedic medicine. The A. sativum extract was found to exhibit slight synergistic activity with gomutra against some tested organism.
From the entire experiment, it can be concluded that A. sativum juice extract with skin have the potential natural antibacterial which cause wound infection and anti fungal compounds. The activity was influenced by gomutra and it was more effective in aqueous extract. However, if plant extracts are to be used for medicinal purposes, issues of safety and toxicity will always need to be considered. Hence I conclude that further research should be carried out on the dosage, in vivo evaluation of the garlic extracts in bandages against infections in a real wound setting.