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- Int J Microbiol
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Int J Microbiol. 2021; 2021: 6087671.
Published online 2021 Aug 7. doi:10.1155/2021/6087671
PMCID: PMC8369171
PMID: 34413890
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- Data Availability Statement
Abstract
This study was designed to assess the antimicrobial potencies of apple vinegar against pathogenic microbes. The acidity and total phenolic content were carried out by titration with NaOH 0.1 N and the Folin–Ciocalteu method, respectively, while the spread plate method, agar well diffusion, and MIC assays were used to determine the antimicrobial activities of different vinegar samples. Acidity and phenolic content were dependent on the variety, where the highest values were observed in S2 with 4.02 ± 0.04% and 1.98 ± 0.05 mg GAE/mL for acidity and total phenolic content, respectively. The spread plate method revealed that samples S1 and S2 obtained from the Red delicious variety and Golden delicious variety, respectively, inhibit the growth of all tested strains, while S3 obtained from different varieties and S4 obtained from the Gala royal variety inhibit only two microbes (Escherichia coli and Vibrio cholerae). Sample S1 presented moderate antimicrobial effect against all examined strains with a diameter of inhibition ranging from 11 ± 0.7 to 19 ± 0.5 mm and with MIC values ranging between 1/2 and 1/100. The findings of the current study confirm the usefulness of apple vinegar as a natural sanitizer that inhibits the growth of pathogenic microbes.
1. Introduction
The development of different methods used to produce food products is closely related to the reduction of infections caused by microorganisms. Moreover, food-borne epidemics continue to be a major public health problem. The profuse use of chemical antibacterial agents is harmful to human health and enhances the incidences of drug-resistant pathogens [1]. Natural products are healthy and safe products that offer antimicrobial effects and antioxidant properties simultaneously [2, 3].
Apple vinegar provides several pharmacological effects, for instance, antidiabetic effect [4–6], anti-Alzheimer effect [7], and antioxidant properties [2]. In addition, the administration of apple vinegar controls body weight gain and enhances glucose tolerance [8]. In experimental trials, the ability of apple vinegar as a natural product has been proved against human pathogens [9]. Thereafter, the sanitizing properties of vinegar have been reviewed in several studies. They reported that apple vinegar has an inhibitory effect against different bacterial strains such as Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus pyogenes, Enterococcus faecalis, Streptococcus pneumoniae, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhi, Enterobacter aerogenes, Klebsiella pneumoniae, Proteus mirabilis, Proteus vulgaris, and Acinetobacter [10, 11]. The remedial properties of apple vinegar are ascribed to its organic acids and its bioactive substances. It has been shown that organic acids pass into bacterial membranes which increases the synthesis of antimicrobial peptides, increases intern osmotic pressure, stimulates the consumption of energy, and sabotages macromolecular synthesis [12]. In addition to organic acids, apple vinegar contains other bioactive compounds that proved their antimicrobial potencies such as phenolic acids and flavonoids [3, 13–17].
In this vision, the present study was designed to determine the acidity and the phenolic content of different vinegar samples as well as their possible antimicrobial action against three bacterial pathogens and two fungal strains.
2. Materials and Methods
2.1. The Sampling of Apple Vinegar
The chosen samples of vinegar were produced by the artisanal process using three varieties of apples as presented in Table 1.
Table 1
The sampling of apple vinegar.
| Samples | Source | Varieties of apple | Stations |
|---|---|---|---|
| S1 | Herbalist Iklil Al-Jabal | Red delicious | Midelt |
| S2 | Herbalist Iklil Al-Jabal | Golden delicious | Midelt |
| S3 | Cooperative Al Jazeera | Different varieties | Midelt |
| S4 | Cooperative Domaine Chène Vert | Gala royal | Sefrou |
2.2. Bacterial and Fungal Strains
A total of five microbial strains, three bacterial strains, and two yeast isolates were used to examine the antimicrobial ability of different vinegar samples. The bacterial strains were represented by Salmonella typhi (CIP 5535), Escherichia coli (CIP 54127), and Vibrio cholerae non-O1-non-O139 isolated from Tamoda Bay [18], while the tested yeasts were represented by Candida albicans (IPL CIM 861484) and Candida tropicalis (Pfizer CIM 4069).
2.3. Determination of Acidity and Total Polyphenolic Content (TPC)
The acidity of different studied samples was determined by titration with 0.1 N NaOH. Results were expressed as a percentage of acetic acid equivalent, while the quantification of the polyphenolic content was carried out using the Folin–Ciocalteu method. Results were expressed as mg of gallic acid equivalent per mL of vinegar (mg GAE/mL) [19].
2.4. Antimicrobial Assay
2.4.1. Spread Plate Method
The test was performed by mixing 100 μL of inocula diluted in physiological saline from broth grown overnight and 4 mL of each sample. The mixture was left for 5 min, and then 100 μL of each mixture was inoculated onto an agar medium. The tests were replicated three times [20].
2.4.2. Sensitivity Assay
(1) Agar Well Diffusion Method. The antimicrobial activity of different samples of vinegar was evaluated using the well diffusion method [10, 21]. The isolates were subjected to antimicrobial activity by the method mentioned above. Salmonella typhi, Escherichia coli O157:H7, and Vibrio cholerae were grown in the Tryptone Casein Soja (TCS) medium, and yeasts Candida albicans and Candida tropicalis were grown in Sabouraud Broth. 100 μL of the active culture of different isolates consisting of 0.5 McFarland 1 ∗ 108 CFU/mL was prepared in physiological saline. 40 μL of the vinegar sample was placed in 5 mm diameter wells that have been cut in the agar of each Petri dish. Negative control wells were filled with sterile physiological water. Petri dishes were incubated at 37°C for 24 h for bacterial strains and at 30°C during 24–48 h for yeasts. Thereafter, the diameter of inhibition zones (DIZ) was measured.
2.4.3. Minimum Inhibitory Concentration Assay (MIC)
The MIC was determined using a microdilution method according to the NCCLS method [21]. Firstly, dilution series of vinegar samples were prepared (S (initial solution), 1/2, 1/4, 1/6, 1/8, 1/10, 1/12, 1/100, and 1/150). Ten μL of each prepared dilution was added to 180 μL of TCS broth and 10 μL of suspension of the active culture of different microorganisms tested (1 ∗ 108 CFU/mL) in microplate wells. The plates were incubated at 37°C for 20 h for bacterial strains and were incubated at 30°C during the same time for yeasts. To reveal the growth of different studied microorganisms, we added to each well 20 μL of the aqueous solution of 0.5% TTC (2,3,5-triphenyltetrazolium chloride), and then plates were incubated at 37°C for 30 min. The lowest dilution with no growth observed was defined as MIC (disappearance of red color after TTC addition) [22].
2.5. Statistical Analysis
ANOVA followed by the Tukey test was used for statistical analysis (P < 0.05) to show if there is any significant difference between samples.
3. Results
3.1. Sample Characterization
Table 2 represents the results of acidity and total phenolic content of different vinegar samples. It is shown that sample S1 had the highest acidity (4.02 ± 0.04%), while the lowest acidity value was registered in sample S4 (0.78 ± 0.07%). Concerning TPC, the highest value (1.98 ± 0.05 mg GAE/mL) was recorded in sample S1, while S4 recorded the lowest value (0.47 ± 0.06 mg GAE/mL).
Table 2
Acidity and polyphenolic content in apple vinegar samples.
| Sample | Acidity (%) | TPC (mg GAE/mL) |
|---|---|---|
| S1 | 4.02 ± 0.04 | 1.98 ± 0.05 |
| S2 | 2.6 ± 0.5 | 1.3 ± 0.0.03 |
| S3 | 1.4 ± 0.09 | 0.88 ± 0.01 |
| S4 | 0.78 ± 0.07 | 0.47 ± 0.06 |
4. The Antimicrobial Ability of Apple Vinegar
4.1. Results of the Spread Plate Method
The results of the spread plate revealed that the growth of different organisms tested was not observed in plates in the presence of samples S1 and S2 as presented in Table 3. The outcomes indicate that samples S1 and S2 were the most effective against all microbes because they inhibited the growth of all tested microorganisms.
Table 3
Results of microorganisms and vinegar samples in the spread plate method.
| Organism | In the presence of vinegar | In the presence of physiological water | |||
|---|---|---|---|---|---|
| S1 | S2 | S3 | S4 | ||
| Salmonella typhi | No growth | No growth | Growth | Growth | Growth |
| Escherichia coli O157:H7 | No growth | No growth | No growth | No growth | Growth |
| Vibrio cholerae | No growth | No growth | No growth | No growth | Growth |
| Candida albicans | No growth | No growth | Growth | Growth | Growth |
| Candida tropicalis | No growth | No growth | Growth | Growth | Growth |
4.2. Results of the Sensitivity Assay
Concerning antimicrobial activity, the vinegar samples were found to have a strong ability to inhibit the growth of microorganisms tested in the present work. Sample S1 produced the best antimicrobial effect against all strains with an inhibition diameter ranging between 12 and 19 mm, whilst sample S4 established the lowest antimicrobial activity. Escherichia coli O157:H7 was the most sensible bacterial strain. On the contrary, samples S3 and S4 presented the lowest activity against Escherichia coli O157:H7 and Vibrio cholerae with the lowest inhibition diameter ranging from 8 to 11 mm, respectively (Table 3). Statistically, there is a significant difference between the effect of vinegar samples studied on bacterial and yeast isolates.
Concerning examined yeasts in the present work, sample S1 was the most active on Candida albicans and Candida tropicalis with a diameter of inhibition ranging between 11 and 12 mm, whilst samples S2, S3, and S4 caused no inhibition of Candida albicans and Candida tropicalis as shown in Table 4.
Table 4
Diameters of inhibition zones (DI) of vinegar samples.
| Organism | Diameter of the inhibition zone (mm) | ||||
|---|---|---|---|---|---|
| S1 | S2 | S3 | S4 | ||
| Bacteria | Salmonella typhi | 15 ± 0.3 | 14 ± 0.9 | No effect | No effect |
| Escherichia coli O157:H7 | 19 ± 0.5 | 13 ± 0.6 | 8 ± 0.3 | 8 ± 0.7 | |
| Vibrio cholerae | 16 ± 0.8 | 14 ± 0.4 | 11 ± 0.5 | 9 ± 0.2 | |
| Yeast | Candida albicans | 12 ± 0.5 | No effect | No effect | No effect |
| Candida tropicalis | 11 ± 0.7 | No effect | No effect | No effect | |
In the present work, the MIC values are shown in Table 5. It was clearly shown that sample S1 exhibited remarkable antimicrobial activity against all microorganisms, with MIC ranging from S to 1/100, followed by sample S2. Amongst all microorganisms tested, E. coli was the most sensitive for all studied vinegar samples, while Candida albicans and Candida tropicalis were more resistant for S2, S3, and S4.
Table 5
Minimum inhibitory concentration (MIC) of vinegar samples.
| Sample | S. typhi | E. coli | V. cholerae | C. albicans | C. tropicalis |
|---|---|---|---|---|---|
| S1 | 1/6 | 1/100 | 1/2 | 1/2 | 1/2 |
| S2 | S | S | S | No effect | No effect |
| S3 | No effect | S | No effect | No effect | No effect |
| S4 | No effect | S | No effect | No effect | No effect |
5. Discussion
Historically, humans have always sought to cure various diseases using different plants and products from the surrounding nature. The emergence of antimicrobial resistance has been paralleled with the misuse of antimicrobial drugs which induces serious problems for human health [23].
Natural products of antimicrobial potency are the best biorational and effective agents as useful bio-antimicrobial drugs [24]. The failure of antibiotics used to eradicate different pathogenic microbes prompted us to study the ability of vinegar to inhibit the growth of pathogenic microbes.
The outcomes revealed that the evaluated vinegar, especially sample S1, has a potent antimicrobial effect against both bacterial strains and fungal isolates. The analysis of results indicates that sample S1 had the highest acidity and phenolic content as compared with other samples (P < 0.05). The values of acidity recorded in different samples are lower than those determined by Moroccan legislation [25]. Furthermore, the obtained results are in line with previous reports [26, 27]. Acidity is a key factor to determine the quality of apple vinegar, and the minimum of vinegar acidity is set at 5 grams of acetic acid equivalent per 100 mL [25]. Organic acids' content determines the flavoring profile of vinegar and depends on the raw material [26]. In addition, vinegar's organic acids play a crucial role in different properties of vinegar such as antimicrobial activities, antidiabetic effects, and anticancer activities [6, 10, 11, 28].
Concerning the phenolic content, the highest value was found in S1. It is considered as an important criterion for quality evaluation [3]. The phenolic content values varied in the range of 1.98 ± 0.05 (S1) to 0.47 ± 0.06 mg GAE/100 mL (S4). These results are in agreement with those reported by Du et al. and Kim et al. [29, 30]. The polyphenolic content of apple vinegar is highly related to the variety of apples, maturity, and geographic location [31]. Secondary metabolites constitute a defense weapon of plants against different pathogenic agents such as fungi, viruses, and bacteria [32]. The efficacy of natural products could be related to their content of bioactive compounds which provide their broad spectrum of antimicrobial activities [33, 34].
Many pathogenic microbes can survive despite the use of antimicrobial chemicals. In the present study, we examined the ability of four vinegar samples to eradicate different pathogenic microbes (bacteria and yeasts). S1 exerted a good activity against all tested microbes with diameter zones ranging from 11 to 12 mm for yeasts and 16 to 19 mm for bacteria, while other samples showed weak antimicrobial activity. The antimicrobial activity could be due to the presence of organic acids, especially acetic acid. Sample S1 registered the highest value of acidity and showed remarkable antimicrobial potency. Our findings are partially coherent with the published studies reporting the efficacy of apple vinegar against Salmonella and Escherichia coli [35], Streptococcus pyogenes [36], Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, Enterococcus faecalis, Streptococcus pneumoniae, Pseudomonas aeruginosa, Pseudomonas fluorescens, Enterobacter aerogenes, Klebsiella pneumoniae, Escherichia coli, Salmonella typhi, Proteus mirabilis, Proteus vulgaris, and Acinetobacter [10], Aspergillus niger, Aspergillus flavus, and Candida albicans [37].
In the literature, several studies showed the efficiency of organic acids against numerous microorganisms [38, 39]. The obtained results could be attributed to the presence of bioactive compounds such as organic acids and phenolic compounds [33, 39–42].
The mechanism of action was recently authored by Zhang et al. in which organic acids display residual effect to prevent the growth of pathogenic microbes [12]. The ability of organic acids to liberate protons H+ into cells decreases intracellular pH, inducing the destruction of bacteria membrane cells [12]. On the contrary, the high levels of hydrogen ions lead to the protonation of cell macromolecules destabilizing the microbes and inducing their death [12]. The expulsion of protons is carried out via active transport which consumes the energy necessary for the normal growth of microbes [13]. In the same context, phenolic compounds present in vinegar could participate in the inhibition processes of microbe's growth. Polyphenols could disturb the integrity of membrane cells which modify their permeability [42] and decrease extracellular pH [43]. Bioactive compounds interact with different intramolecular ingredients of cells [44], forming complexes and affecting the processes of energy production and protein synthesis [45].
Furthermore, the interaction between bioactive compounds and organism's cell surfaces is liable for the antimicrobial effect of vinegar [42]. It was found that apple vinegar contains several phenolic compounds such as vanillic acid, chlorogenic acid, caffeic acid, gallic acid, catechin, epicatechin gallate, and phlorizin [29]. It has been documented that chlorogenic acid effectively alleviates lung infection in Klebsiella pneumonia-infected mice and provides a remarkable antibacterial activity [46]. Similarly, Carvalho et al. showed that tannin and gallic acid are suggested to be antimicrobial agents through the inhibition of catalase and binding membrane ergosterol [47]. The co*cktail composition of vinegar provides it the ability to inhibit the growth of different organisms through the synergy between its active ingredients which confirm their antimicrobial potencies.
6. Conclusion
In the present work, the evaluated apple vinegar samples, especially S1, demonstrated an adequate antimicrobial potency against different studied strains. Functional properties of apple vinegar could be related to the presence of organic acids and phenolic compounds. Vinegar, as an organic product, could be used as a natural sanitizer and also as a bioactive ingredient in the food industry.
Acknowledgments
The authors are grateful to their colleagues who helped in collecting data and the agricultural cooperatives in Midelt and Sefrou.
Data Availability
The data used to support the findings of this study are included within the article.
Conflicts of Interest
The authors declare that there are no conflicts of interest.
References
1. Ahmad M., Khan A. U. Global economic impact of antibiotic resistance: a review. Journal of Global Antimicrobial Resistance. 2019;19:313–316. doi:10.1016/j.jgar.2019.05.024. [PubMed] [CrossRef] [Google Scholar]
2. Bakir S., Toydemir G., Boyacioglu D., Beekwilder J., Capanoglu E. Fruit antioxidants during vinegar processing: changes in content and in vitro bio-accessibility. International Journal of Molecular Sciences. 2016;17(10):p. 1658. doi:10.3390/ijms17101658. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
3. Ousaaid D., Imtara H., Laaroussi H., Lyoussi B., Elarabi I. An investigation of Moroccan vinegars: their physicochemical properties and antioxidant and antibacterial activities. Journal of Food Quality. 2021;2021 doi:10.1155/2021/6618444.e6618444 [CrossRef] [Google Scholar]
4. Lheman J., Sutiono A., Yanti Y., Tjandrawinata R. R., Lay B. W. Functional Bignay Ciders inhibit key enzymes linked to obesity and diabetes for metabolic syndrome protection. Jurnal Teknologi. 2021;83(2):67–75. doi:10.11113/jurnalteknologi.v83.14898. [CrossRef] [Google Scholar]
5. Ahmadniaye Motlagh H., Javadmanesh A., Safari O. Improvement of non-specific immunity, growth, and activity of digestive enzymes in Carassius auratus as a result of apple cider vinegar administration to diet. Fish Physiology and Biochemistry. 2020;46(4):1387–1395. doi:10.1007/s10695-020-00797-6. [PubMed] [CrossRef] [Google Scholar]
6. Ousaaid D., Laaroussi H., Bakour M., et al. Beneficial effects of apple vinegar on hyperglycemia and hyperlipidemia in hypercaloric-fed rats. Journal of Diabetes Research. 2020;2020:7. doi:10.1155/2020/9284987.9284987e9284987 [PMC free article] [PubMed] [CrossRef] [Google Scholar]
7. Tripathi S., Mazumder P. M. Apple cider vinegar (ACV) and their pharmacological approach towards alzheimer’s disease (AD): a review. Indian Journal of Pharmaceutical Education and Research. 2020;54(2s):s67–s74. doi:10.5530/ijper.54.2s.62. [CrossRef] [Google Scholar]
8. Urtasun R., Díaz-Gómez J., Araña M., et al. A combination of apple vinegar drink with Bacillus coagulans ameliorates high fat diet-induced body weight gain, insulin resistance and hepatic steatosis. Nutrients. 2020;12(9):p. 2504. doi:10.3390/nu12092504. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
9. Rutala W. A., Barbee S. L., Aguiar N. C., Sobsey M. D., Weber D. J. Antimicrobial activity of home disinfectants and natural products against potential human pathogens. Infection Control & Hospital Epidemiology. 2000;21(1):33–38. doi:10.1086/501694. [PubMed] [CrossRef] [Google Scholar]
10. Hindi N. K. In vitro antibacterial activity of aquatic garlic extract, apple vinegar and apple vinegar-garlic extract combination. American Journal of Phytomedicine and Clinical Therapeutics. 2013;1(1):42–51. [Google Scholar]
11. Hindi N. K. K., Al-Mahdi Z. K. A., Chabuck Z. A. G. Antibacterial activity of the aquatic extractof fresh, dry powder ginger, apple vinegar extract of fresh ginger and crud oil of ginger (zingiberofficinale) against different types of bacteria in Hilla City, Iraq. Prostate. 2014;3:p. 6. [Google Scholar]
12. Zhang J., Tian Z. G., Wang J. H., Wang A. R. Advances in antimicrobial molecular mechanism of organic acids. Acta Veterinaria et Zootechnica Sinica- Chinese Journal of Animal Science and Veterinary. 2011;42(3):323–328. [Google Scholar]
13. Cherrington C. A., Hinton M., Mead G. C., Chopra I. Organic acids: chemistry, antibacterial activity and practical applications. Advances in Microbial Physiology. 1991;32:87–108. doi:10.1016/s0065-2911(08)60006-5. [PubMed] [CrossRef] [Google Scholar]
14. Xia T., Zhang B., Duan W., Zhang J., Wang M. Nutrients and bioactive components from vinegar: a fermented and functional food. Journal of Functional Foods. 2020;64 doi:10.1016/j.jff.2019.103681.103681 [CrossRef] [Google Scholar]
15. Zhang B., Xia T., Duan W., et al. Effects of organic acids, amino acids and phenolic compounds on antioxidant characteristic of Zhenjiang aromatic vinegar. Molecules. 2019;24(20):p. 3799. doi:10.3390/molecules24203799. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
16. Adamczak A., Ożarowski M., Karpiński T. M. Antibacterial activity of some flavonoids and organic acids widely distributed in plants. Journal of Clinical Medicine. 2020;9(1):p. 109. doi:10.3390/jcm9010109. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
17. Cowan M. M. Plant products as antimicrobial agents. Clinical Microbiology Reviews. 1999;12(4):564–582. doi:10.1128/cmr.12.4.564. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
18. Abdelkhalek B., Quilici M.-L., Abdelaziz F., Nozha C. Occurrence of pathogenic Vibrio species in Tamouda Bay (Morocco) Journal of Microbiology Research. 2013;3(6):240–246. doi:10.5923/j.microbiology.20130306.08. [CrossRef] [Google Scholar]
19. Ousaaid D., Mansouri I., Laaroussi H., Lyoussi B., El Arabi I. Physicochemical properties and antioxidant activity of two varieties of apple cultivated in different areas in Morocco. Mediterranean Journal of Chemistry. 2020;10(4):371–377. [Google Scholar]
20. Jay J. M., Loessner M. J., Golden D. A. Modern Food Microbiology. Berlin, Germany: Springer Science & Business Media; 2008. [Google Scholar]
21. Clinical and Laboratory Standards Institute. CLSI Document M07-A9. Vol. 32. Wayne, PA, USA: Clinical and Laboratory Standards Institute; 2012. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically; approved standard. [Google Scholar]
22. Dimitrijević D., Stanković M., Stojanović-Radić Z., Ran\djelović V., Lakuscaron D. Antioxidant and antimicrobial activity of different extracts from leaves and roots of Jovibarba heuffelii (Schott.) A. Lve and D. Lve. Journal of Medicinal Plants Research. 2012;6(33):4804–4810. [Google Scholar]
23. Molton J. S., Tambyah P. A., Ang B. S. P., Ling M. L., Fisher D. A. The global spread of healthcare-associated multidrug-resistant bacteria: a perspective from Asia. Clinical Infectious Diseases. 2013;56(9):1310–1318. doi:10.1093/cid/cit020. [PubMed] [CrossRef] [Google Scholar]
24. Veeresham C. Natural products derived from plants as a source of drugs. Journal of Advanced Pharmaceutical Technology & Research. 2012;3(4):p. 200. doi:10.4103/2231-4040.104709. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
25. DEC.2-10-385.FR.pdf. 2020. http://www.onssa.gov.ma/images/reglementation/reglementation-sectorielle/vegetaux-et-produits-dorigine-vegetaux/Produits-dorigine-vegetale/Produits_alimentaires/DEC.2-10-385.FR.pdf.
26. Joshi V. K., Sharma S. Vinegars of the World. Berlin, Germany: Springer; 2009. Cider vinegar: microbiology, technology and quality; pp. 197–207. [CrossRef] [Google Scholar]
27. Sung N.-H., Woo S.-M., Kwon J.-H., Yeo S.-H., Jeong Y.-J. Quality characteristics of high acidity apple vinegar manufactured using two stage fermentation. Journal of the Korean Society of Food Science and Nutrition. 2014;43(6):877–883. doi:10.3746/jkfn.2014.43.6.877. [CrossRef] [Google Scholar]
28. Baba N., Higashi Y., Kanekura T. Japanese black vinegar “Izumi” inhibits the proliferation of human squamous cell carcinoma cells via necroptosis. Nutrition and Cancer. 2013;65(7):1093–1097. doi:10.1080/01635581.2013.815234. [PubMed] [CrossRef] [Google Scholar]
29. Du G., Zhu Y., Wang X., et al. Phenolic composition of apple products and by-products based on cold pressing technology. Journal of Food Science & Technology. 2019;56(3):1389–1397. doi:10.1007/s13197-019-03614-y. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
30. Kim S.-H., Cho H.-K., Shin H.-S. Physicochemical properties and antioxidant activities of commercial vinegar drinks in Korea. Food Science and Biotechnology. 2012;21(6):1729–1734. doi:10.1007/s10068-012-0230-y. [CrossRef] [Google Scholar]
31. Solieri L., Giudici P. Vinegars of the World. Berlin, Germany: Springer; 2009. pp. 1–16. [CrossRef] [Google Scholar]
32. Freeman B. C., Beattie G. A. The Plant Health Instructor. 2008. An overview of plant defenses against pathogens and herbivores. [CrossRef] [Google Scholar]
33. Bhilabutra W., Techowisan T., Peberdy F. J., Lumyong S. Antimicrobial activity of bioactive compounds from Periconia siamensis CMUGE015. Research Journal of Microbiology. 2007;2(10):749–755. doi:10.3923/jm.2007.749.755. [CrossRef] [Google Scholar]
34. Viswanathan M. B. G., Jeya Ananthi J. D., Sathish Kumar P. Antimicrobial activity of bioactive compounds and leaf extracts in Jatropha tanjorensis. Fitoterapia. 2012;83(7):1153–1159. doi:10.1016/j.fitote.2012.07.007. [PubMed] [CrossRef] [Google Scholar]
35. Shah Q. A., Bibi F., Shah A. H. Anti-microbial effects of olive oil and vinegar against salmonella and Escherichia coli. PJST. 2013;14(2):479–486. [Google Scholar]
36. Ismael N. F. “Vinegar” as anti-bacterial biofilm formed by Streptococcus pyogenes isolated from recurrent tonsillitis patients, in vitro. Jordan Journal of Biological Sciences. 2013;6(3) doi:10.12816/0001532. [CrossRef] [Google Scholar]
37. Jabir H. B., Abbas F. N., Khalaf R. M. In vitro assessment of antifungal potential of apple cider vinegar and acetic acid versus fluconazole in clinical isolates of otomycosis. Thi-Qar Medical Journal. 2011;5(1):126–133. [Google Scholar]
38. Wali M. K., Abed M. M. Antibacterial activity of acetic acid against different types of bacteria causes food spoilage. Plant Archives. 2019;19(1):1827–1831. [Google Scholar]
39. Adamczak A., Ożarowski M., Karpiński T. M. Antibacterial activity of some flavonoids and organic acids widely distributed in plants. Journal of Clinical Medicine. 2019;9(1) doi:10.3390/jcm9010109. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
40. Carrol D. H., Chassagne F., Dettweiler M., Quave C. L. Antibacterial activity of plant species used for oral health against Porphyromonas gingivalis. PLoS One. 2020;15(10) doi:10.1371/journal.pone.0239316.e0239316 [PMC free article] [PubMed] [CrossRef] [Google Scholar]
41. Borges A., Ferreira C., Saavedra M. J., Simões M. Antibacterial activity and mode of action of ferulic and gallic acids against pathogenic bacteria. Microbial Drug Resistance. 2013;19(4):256–265. doi:10.1089/mdr.2012.0244. [PubMed] [CrossRef] [Google Scholar]
42. Bouarab-Chibane L., Forquet V., Lantéri P., et al. Antibacterial properties of polyphenols: characterization and QSAR (quantitative structure-activity relationship) models. Frontiers in Microbiology. 2019;10:p. 829. doi:10.3389/fmicb.2019.00829. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
43. Pernin A., Guillier L., Dubois-Brissonnet F. Inhibitory activity of phenolic acids against Listeria monocytogenes: deciphering the mechanisms of action using three different models. Food Microbiology. 2019;80:18–24. doi:10.1016/j.fm.2018.12.010. [PubMed] [CrossRef] [Google Scholar]
44. Botton B., Breton A., Febre M., et al. Useful and Harmful Moulds. Industrial Importance. 2nd. Masson, Paris, France: 1990. [Google Scholar]
45. Djilani A., Dicko A. The therapeutic benefits of essential oils. Nutrition: Tips for Improving Your Health. 2012;7:155–179. doi:10.5772/25344. [CrossRef] [Google Scholar]
46. Tan S., Gao J., Li Q., et al. Synergistic effect of chlorogenic acid and levofloxacin against Klebsiella pneumonia infection in vitro and in vivo. Scientific Reports. 2020;10(1):p. 20013. doi:10.1038/s41598-020-76895-5. [PMC free article] [PubMed] [CrossRef] [Google Scholar]
47. Carvalho R. S., Carollo C. A., de Magalhães J. C., et al. Antibacterial and antifungal activities of phenolic compound-enriched ethyl acetate fraction from Cochlospermum regium (mart. Et. Schr.) Pilger roots: mechanisms of action and synergism with tannin and gallic acid. South African Journal of Botany. 2018;114:181–187. doi:10.1016/j.sajb.2017.11.010. [CrossRef] [Google Scholar]
Articles from International Journal of Microbiology are provided here courtesy of Hindawi Limited
I must say, this article dives deep into the antimicrobial potential of apple vinegar. From the acidity and total phenolic content assessments to various antimicrobial assays, the study leaves no stone unturned. The authors, including Driss Ousaaid and his team, have meticulously explored the effects of apple vinegar on a range of pathogenic microbes, presenting a detailed methodology and comprehensive results.
Now, let's break down some of the key concepts used in this study:
-
Acidity and Total Phenolic Content:
- Acidity was determined by titration with NaOH 0.1 N.
- Total phenolic content was measured using the Folin–Ciocalteu method.
- The values varied based on the variety of apples, with S2 exhibiting the highest acidity and phenolic content.
-
Antimicrobial Assays:
- The spread plate method, agar well diffusion, and MIC assays were employed to assess antimicrobial activities.
- Sample S1 from the Red delicious variety showed the most potent antimicrobial effect against various strains, with significant inhibition zones and low MIC values.
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Microbial Strains:
- Three bacterial strains (Salmonella typhi, Escherichia coli, Vibrio cholerae) and two yeast isolates (Candida albicans, Candida tropicalis) were used in the study.
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Sampling of Apple Vinegar:
- Four vinegar samples (S1, S2, S3, S4) were obtained from different varieties and sources, including Red delicious, Golden delicious, different varieties, and Gala royal.
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Data Analysis:
- ANOVA followed by the Tukey test was used for statistical analysis.
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Results:
- Sample S1 showed the highest acidity and total phenolic content, correlating with its potent antimicrobial effects.
- The spread plate method revealed the inhibitory effects of S1 and S2 against all tested strains.
- Antimicrobial assays (agar well diffusion and MIC) confirmed the effectiveness of apple vinegar, particularly S1.
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Discussion:
- The discussion delves into the historical use of natural products for disease treatment and the emergence of antimicrobial resistance.
- The study supports the antimicrobial efficacy of apple vinegar, attributing it to organic acids and phenolic compounds.
- The mechanism of action involves the disruption of microbial membranes and interference with essential cellular processes.
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Conclusion:
- The conclusion highlights the antimicrobial potency of apple vinegar, especially sample S1, suggesting its potential use as a natural sanitizer and bioactive ingredient in the food industry.
Overall, this research contributes valuable insights into the application of apple vinegar as a natural antimicrobial agent, providing a scientific basis for its potential benefits in food safety and health.
