Anti Microbial Properties - Bibliography by Topic
Abstract: The present report presents quantitative data with respect to the required bacteriostatic and lethal concentrations of several quinones against two species of gram-positive pathogenic cocci.
Banu, A., Sathyanarayana, B. C., and Chattannavar, G. (2012). Efficacy of fresh Aloe vera gel against multi--drug resistant bacteria in infected leg ulcers. Australasian Medical Journal, 5(6), 305-309.
Abstract: Infected leg ulcers are major health problems resulting in morbidity and disability and are usually chronic and refractory to antimicrobial treatment. Aims: The recent study is aimed at determining the bacteria involved in leg ulcers and their resistance patterns to commonly used antibiotics as well as to determine whether Aloe Vera has antibacterial activity against multi-drug-resistant organisms and promotes wound healing. Method: A total of 30 cases with leg ulcers infected with multi-drug-resistant organisms were treated with topical aloe vera gel and 30 age and sex-matched controls were treated with topical antibiotics. Culture and sensitivity was done from the wounds on alternate days and the ulcer was clinically and microbiologically assessed after 10 days. The results were compiled and statistically analysed. Results: Cultures of the study group who were using aloe vera dressings showed no growth by the fifth day in 10 (33.3%) cases, seventh day in another 16 (53.3%) and ninth day in two of the remaining four cases (6.7%) while in two (6.7%) cases, there was no decrease in the bacterial count. This means that of the 30 cases, 28 showed no growth by the end of 11 days while two cases showed no decrease in bacterial count. Growth of bacteria in study group decreased from 100% (30 cases) to 6.7% (2 cases) by day 11 with P<0.001. Cultures of the control group did not show any decrease in the bacterial growth by day 11. Conclusion: Aloe vera gel preparation is cheap and was effective even against multi-drug-resistant organisms as compared to the routinely used topical antimicrobial agents.
Abstract: We prepared a crude gel material from Aloe vera succulent leaf tissues. The ethanolic extract of lyophilized A. vera gel was used for the GC-MS analysis. Hexadecanoic acid (22.22%) was identified as major compound. Sitosterol and stigmasterol were found to be 2.89% and 2.1% in the extract. HPLC analysis was carried out to confirm the presence of stigmasterol. The concentration of sterol extract needed to scavenge DPPH free radical by 50% was calculated as 5.2 mg mL-1. In the FRAP assay, the sterol extract showed significant hydroxyl radical scavenging in a dose-dependent manner (IC50 value 1.17 µg mL-1). Concentration of the sample required to reduce lipid peroxidation was found to be 4.18 µg mL-1, and the extract also possessed acetylcholinesterase activity (IC50 - 5.26 µg mL-1). Catalase activity was 0.196 µM H2O2 decomposed min-1 µg-1 protein, whereas the peroxidase activity was 17.01 µM of pyragallol oxidized min-1 µg-1 protein. The extract recorded higher activity against growth of S. greseus and C. albicans in the experiments carried out to determine antibacterial and antifungal activity, respectively.
Bazvand, L., Aminozarbian, M. G, Farhad, A., Noormohammadi, H., Hasheminia, S. M., and Mobasherizadeh, S. (2014, July). Antibacterial effect of triantibiotic mixture, chlorhexidine gel, and two natural materials Propolis and Aloe vera against Enterococcus faecalis: An ex vivo study. Dental Research Journal, 11(4), 469-475.
Abstract: The aim of this ex vivo study was to compare the antimicrobial effect of triantibiotic paste, 0.2% chlorhexidine gel, Propolis and Aloe vera on Enterococcus faecalis in deep dentin. Ninety fresh extracted single-rooted teeth were used in a dentin block model. Seventy-five teeth were infected with E. faecalis and divided into four experimental groups (n = 15). Experimental groups were treated with triantibiotic mixture with distilled water, 0.2% chlorhexidine gel, 70% ethanol + Propolis and Aloe vera. Fifteen teeth treated with distilled water as the positive control and 15 samples, free of bacterial contamination, were considered as the negative control. Gates-Glidden drill #4 was used for removal of surface dentin and Gates-Glidden drill #5 was used to collect samples of deep dentin. The samples were prepared and colony-forming units were counted. Data were analyzed by one-way ANOVA and post hoc Tukey tests. Statistical significance was defined at P < 0.05. Results: Triantibiotic mixture group exhibited the least bacterial growth. However, the rate of bacterial growth showed no significant differences between chlorhexidine and Propolis groups (P > 0.05). Aloe vera had antibacterial effects on E. faecalis, but in comparison with other medicaments, it was less effective (P < 0.05). Conclusion: This experimental study showed that triantibiotic mixture, 0.2% chlorhexidine gel, Propolis and Aleo vera were relatively effective against E. faecalis. All the intracanal medicements had similar effects on E. faecalis in deep dentin except for Aloe vera.
Bertolini, P. F. R., Filho, O. B., Pomilio, A., Pinheiro, S. L., and De Carvalho, M. S. (2012). Antimicrobial capacity of Aloe vera and propolis dentifrice against Streptococcus mutans strains in toothbrushes: an in vitro study. J Appl Oral Sci., 20(1), 32-37.
Abstract: This study evaluated in vitro the efficiency of Aloe vera and propolis dentifrice on reducing the contamination of toothbrush bristles by a standard strain of Streptococcus mutans (ATCC 25175; SM), after toothbrushing. Material and Methods: Fifteen sterile toothbrushes were randomly divided into 5 toothbrushing groups: I (negative control): without dentifrice; II: with fluoridated dentifrice; III: with triclosan and gantrez dentifrice; IV (positive control): without dentifrice and irrigation with 10 mL of 0.12% chlorhexidine gluconate; V: with Aloe vera and propolis dentifrice. In each group, 1 sterile bovine tooth was brushed for 1 min, where the toothbrush bristles were contaminated with 25 µL of SM. After toothbrushing, the bristles were stored in individual test tubes with 3 mL of BHI under anaerobiosis of 37°C for 48 h. Then, they were seeded with sterile swab in triplicate in the Mitis salivarius: Bacitracin culture medium. The samples were kept under anaerobiosis of 37°C for 48 h. Scores were used to count the number of colony forming units (cfu). The results were submitted to the Mann-Whitney statistical test at 5% significance level. Results: There was statistically significant difference (p<0.05) for the reduction of bristle contamination comparing groups II, III, IV and V to group I. Conclusions: It may be stated that after toothbrushing, the Aloe vera and propolis dentifrice reduced the contamination of toothbrush bristles by SM, without differentiation from the other chemical agents used.
Cellini, L., Di Bartolomeo, S., Di Campli, E., Genovese, S., Locatelli, M., and Di Giulio, M. (2014). In vitro activity of Aloe vera inner gel against Helicobacter pylori strains. Letters in Applied Microbiology, 59, 43-48.
Abstract: Aloe barbadensis Miller (Aloe vera) is a herbal remedy widely used for a variety of illnesses; A. vera leaf extracts have been promoted for detoxification, cure constipation, help flush out toxins and wastes from the body, promote digestion and are used in the treatment of peptic ulcer for cytoprotective action. The aim of this study was to evaluate the antibacterial activity of A. vera inner gel against both susceptible and resistant Helicobacter pylori strains isolated in Abruzzo region, Italy. The inner gel of leaves of a 5-year-old plant of A. vera was extracted, homogenized and tested from 800 to 1.56 mg ml-1 against 14 clinical strains and one reference strain of H. pylori using the broth microdilution methodology. Furthermore, the sample of A. vera was investigated for the chemical fingerprint of anthraquinones. The inhibitory concentrations of A. vera inner gel were similar to the bactericidal ones, with values ranging from 6.25 to 800 mg ml-1 . Fifty percent of the detected strains, independently of their susceptibility profile, were inhibited in their growth at 100 mg ml-1 . Aloe vera inner gel expresses antibacterial properties against H. pylori and, therefore, in combination with antibiotics, could represent a novel strategy for the treatment of the infection of H. pylori, especially in cases of multi-resistance.
Dahiya, P., and Purkayastha, S. (2012, September). Phytochemical screening and antimicrobial activity of some medicinal plants against multi-drug resistant bacteria from clinical isolates. Indian Journal of Pharmaceutical Sciences, 4(5), 443-450.
Abstract: The in vitro antibacterial activity of various solvents and water extracts of aloe vera, neem, bryophyllum, lemongrass, tulsi, oregano, rosemary and thyme was assessed on 10 multi-drug resistant clinical isolates from both Gram-positive and Gram-negative bacteria and two standard strains including Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922. The zone of inhibition as determined by agar well diffusion method varied with the plant extract, the solvent used for extraction, and the organism tested. Klebsiella pneumoniae 2, Escherichia coli 3 and Staphylococcus aureus 3 were resistant to the plant extracts tested. Moreover, water extracts did not restrain the growth of any tested bacteria. Ethanol and methanol extracts were found to be more potent being capable of exerting significant inhibitory activities against majority of the bacteria investigated. Staphylococcus aureus 1 was the most inhibited bacterial isolate with 24 extracts (60%) inhibiting its growth whereas Escherichia coli 2 exhibited strong resistance being inhibited by only 11 extracts (28%). The results obtained in the agar diffusion plates were in fair correlation with that obtained in the minimum inhibitory concentration tests. The minimum inhibitory concentration of tulsi, oregano, rosemary and aloe vera extracts was found in the range of 1.56-6.25 mg/ml for the multi-drug resistant Staphylococcus aureus isolates tested whereas higher values (6.25-25 mg/ml) were obtained against the multi-drug resistant isolates Klebsiella pneumoniae 1 and Escherichia coli 1 and 2. Qualitative phytochemical analysis demonstrated the presence of tannins and saponins in all plants tested. Thin layer chromatography and bioautography agar overlay assay of ethanol extracts of neem, tulsi and aloe vera indicated flavonoids and tannins as major active compounds against methicillin-resistant Staphylococcus aureus.
Abstract: A method of reducing depolymerization and/or deterioration of aqueous dispersions of aloe polysaccharide compositions by the effects of bacteria, fungi and enzymes, comprising mixing the aloe polysaccharide or its aqueous dispersion with a gum selected from a group consisting of guar gum and locust bean gum, either in dry form or in aqueous dispersions of the gum.
Gottshall, R. Y., Lucas, E. H., Lickfeldt, A., and Roberts, J. M. (1949). The occurrence of antibacterial substances active against mycobacterium tuberculosis in seed plants. Journal of Clinical Investigation, 28, 920-923.
Abstract: The antibacterial activity against M. tuberculosis, strain H37, of 211 plant samples from 161 species belonging to 53 families of seed plants was determined by serial dilution tests.
Gupta, R. K., Gupta D., Bhaskar D. J., Yadav A., Obaid, K., and Mishra, S. (2014, April). Preliminary antiplaque efficacy of aloe vera mouthwash on 4 day plaque re-growth model: Randomized control trial. Ethiop J Health Sci., 24(2), 139-145.
Abstract: Due to increasing resistance to antibiotics and rising incidence of oral diseases, there is a need for alternative treatment modalities to combat oral diseases. The aim of the present study was to access the effect of Aloe vera mouthwash on the dental plaque in the experimental period of 4 days and to compare it with the bench mark control chlorhexidine and placebo (saline water). Material and Methods: A total of 300 systemically healthy subjects were randomly allocated into 3 groups: Aloe vera mouthwash group (n=100), control group (=100)-chlorhexidene group and saline water-placebo (n=100). To begin with, gingival index (GI) and plaque index (PI) were recorded. Then, baseline plaque scores were brought to zero by professionally cleaning the teeth with scaling and polishing. After randomization of the participants into three groups they were refrained from regular mechanical oral hygiene measures. Subjects were asked to swish with respective mouthwash (Aloe vera mouthwash, 0.2% chlorhexidine gluconate mouthwash, or normal saline) as per therapeutic dose for 4 days. Results: The results showed that Aloe vera mouthrinse is equally effective in reducing plaque as Chlorhexidine compared to placebo over a period of 4 days. There was a significant reduction on plaque in Aloe vera and chlorhexidine groups and no statistically significant difference was observed among them (p>0.05). Aloe vera mouthwash showed no side effects. Conclusion: The results of the present study indicated that Aloe vera may prove an effective mouthwash due to its ability in reducing dental plaque.
Heggers, J. P., Pineless, G. R., and Robson, M. C. (1979, September/October). Dermaide Aloe / Aloe vera gel: Comparison of the antimicrobial effects. Journal of American Medical Technologists,41(5), 293-294.
Abstract: This article from the University of Chicago Burn Center records a comparison between two Aloe vera products as to their comparative antimicrobial activity which is important in the treatment of burns and many other injuries. Aloe inhibits the growth of some of the most dangerous microbes.
Abstract: Aloe vera has been used worldwide both for pharmaceutical, food, and cosmetic industries due to the plethora of biological activities of some of its metabolites. The aim of this study was to evaluate the antifungal and antioxidant activities of the leaf extract. The antifungal activity was determined by the agar-well diffusion method against plant and human fungal pathogens. The methanol and ethanol portions of the extracts studies were more bioactive than ethyl acetate portion. It was also observed that the activity was more pronounced on plant pathogen than human pathogen except Candida albicans. This is an indication that the extract has the potential to treat plant fungal infections. The Aloe extract showed the significant antioxidant activity by the DPPH radical scavenging method. Therefore, the Aloe extract provided as natural antioxidant has been used in health foods for medical and preservative purposes.
Abstract: Antibacterial property of Aloe vera. Freeze-dried juice obtained from Aloe vera and heated for 15 minutes at 80° inhibited several test microorganisms.
Abstract: The aim of this study was to identify, quantify, and compare the phytochemical contents, antioxidant capacities, and antibacterial activities of Aloe vera lyophilized leaf gel (LGE) and 95% ethanol leaf gel extracts (ELGE) using GC-MS and spectrophotometric methods. Analytically, 95% ethanol is less effective than ethyl acetate/diethyl ether or hexane (in the case of fatty acids) extractions in separating phytochemicals for characterization purposes. However, although fewer compounds are extracted in the ELGE, they are approximately 345 times more concentrated as compared to the LGE, hence justifying ELGE use in biological efficacy studies in vivo. Individual phytochemicals identified included various phenolic acids/polyphenols, phytosterols, fatty acids, indoles, alkanes, pyrimidines, alkaloids, organic acids, aldehydes, dicarboxylic acids, ketones, and alcohols. Due to the presence of the antioxidant polyphenols, indoles, and alkaloids, the A. vera leaf gel shows antioxidant capacity as confirmed by ORAC and FRAP analyses. Both analytical methods used show the non-flavonoid polyphenols to contribute to the majority of the total polyphenol content. Three different solvents such as aqueous, ethanol, and acetone were used to extract the bioactive compounds from the leaves of A. vera to screen the antibacterial activity selected human clinical pathogens by agar diffusion method. The maximum antibacterial activities were observed in acetone extracts (12 + 0.45, 20 + 0.35, 20 + 0.57, and 15 + 0.38 nm) other than aqueous and ethanol extracts. Due to its phytochemical composition, A. vera leaf gel may show promise in alleviating symptoms associated with/or prevention of cardiovascular diseases, cancer, neurodegeneration, and diabetes.
Pareek, S., Nagaraj, A., Sharma, P., Atri, M., and Walia, S., Naidu, S., and Yousuf, A. (2013). Disinfection of dental unit water line using aloe vera: In vitro study. International Journal of Dentistry, 1-6.
Abstract: Dental unit waterlines may be heavily contaminated with microorganisms and are a potential source of infection for both practicing staff and immunocompromised patients particularly. Contamination of dental unit water lines could be inhibited with the use of disinfectants. The present study investigates the effect of aloe-vera-based disinfectant in reducing the microbial growth in dental unit water lines (DUWLs). Aims. To compare the efficacy of aloe vera, hydrogen peroxide (H2O2), and 5%sodium hypochlorite (NaOCl) in controlling microbial contamination of DUWLs. Materials and Methods. After obtaining baseline water samples, the dental unit waterlines were treated with aloe vera, 10% hydrogen peroxide, and 5% sodium hypochlorite. Each of the three disinfectants was used in increasing concentrations and their inhibiting effect was compared. Water samples were analyzed for microbiological quality by the total viable count (TVC) method. Statistical Analysis Used.SPSS16. Results: There was significant reduction in mean CFU/ml when treated with disinfectants each for a period of one week. Aloe-vera solution was found to be the most effective in reducing the microbial colonies. Conclusions. Improving the water quality from dental unit water lines is of considerable importance; chemical-based disinfectants can be replaced with herbal disinfectants for treating microbial contamination in dental unit waterlines.
Abstract: Aloe vera has been tested against a variety of infections--viral, bacterial, and fungal. The exudate of Aloe has been confirmed again and again as having direct antimicrobial effects, killing invading pathological organisms. However, the principal benefits of Aloe with regard to infective agents comes from aloin-free or dealoinized extracts, which work by strengthening the body's own defenses. This newsletter closely examines these functions of Aloe.
Abstract: Specialized molecules in Aloe vera whole leaf extract interact with some special "receptor" substances that are embedded into the outer membrane of our immune system cells. The result is that the immune system cells are galvanized into action. In particular, the class of cells known as "phagocytes" increase the activities by which they attack and then engulf bacteria, waste products and debris. This increase in scavenging activities cleanses and protects the body, with knock-on benefits for a whole cascade of different medical conditions. The literature indicates that a common mechanism in this respect probably exists in both humans and animals and that both can benefit enormously from the use of Aloe vera.
Abstract: Mediators released during inflammatory response play an essential role in eliminating microbes or microbial products. However, the uncontrolled release of cytotoxic substances characterized by extensive inflammation may adversely affect normal tissues. Under such conditions it is important to manage the hyper-inflammation in order to change the clinical manifestations of the disease. Accordingly, the present study was designed to evaluate the modulation of Salmonella OmpR mediated inflammation by Aloe vera, a plant known to contain anti-inflammatory ingredients. It was observed that outer-membrane proteins (OMPs) extracted from the wild type strain of S. typhimurium caused inflammation of greater magnitude compared with the OMPs extracted from its mutant construct as evident from the oedema test as well as the hyperalgesic (flicking) response of the animals under experimental conditions. However, Aloe vera applied topically, administered intraperitoneally or in combination modulated the inflammatory response. The maximum effect was observed with the combined formulation indicating modulation at local as well as systemic levels. The results reveal that this modulation could be due to the potential of Aloe vera to decrease peroxidative damage via a decrease in the levels of monokines (TNFα, IL-1, and IL-6) and an increase in the level of superoxide dismutase (SOD). Moreover, the presence of SOD in Aloe vera itself might be responsible for enhancing its levels in the macrophages. On the other hand, no significant change in the catalase activity was observed by Aloe vera treatment. The use of Aloe vera, therefore, seems to have a promising role in the modulation of Salmonella OmpR mediated inflammation.
Abstract: These experimental data clearly show that the effects elicited by the Aloe vera extract are truly beneficial in a burn wound.
Abstract: Aloe vera fresh leaves hydroalcoholic plant extract was tested against the mycelial growth of Botrytis gladiolorum, Fusarium oxysporum f.sp. gladioli, Heterosporium pruneti and Penicillium gladioli on Czapek-agar medium. The minimum fungicidal concentration (MFC) varied between 80 and 100 µL/ml, depending on the fungal species.
Abstract: One of the many studies made by the Japanese and Koreans. It is a positive report of another type of Aloe plant, known as Cape Aloe, which shows that it, too, has very fine medicinal qualities.
Abstract: Very short article on anti-bacterial and anti-fungal activity of Cape Aloe.
Abstract: Sepsis is an acute life-threatening clinical condition and remains the major cause of death in intensive care units. The primary pathophysiologic event central to the septic response is an overwhelming activation of the inflammatory system and countervailing response from the anti-inflammatory system. However, the cause of this perturbation has yet to be elucidated. In this study, we report that Aloe vera therapeutically reverses the lethality induced by cecal ligation and puncture (CLP), a clinically relevant model of sepsis. The administration of Aloe vera ameliorated the multiple organ dysfunction syndrome, as evidenced by the serum levels of biochemical parameters and histological changes. In order to investigate the pharmacological mechanism of Aloe vera, the levels of the cytokines, tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 were determined by ELISA at various time points. The increases in the levels of TNF-α, IL-1β, and IL-6 were attenuated by Aloe vera. In vivo administration of Aloe vera also markedly enhanced bacterial clearance. Our findings suggest that Aloe vera could be a potential therapeutic agent for the clinical treatment of sepsis.