Antimicrobial Activity Of Aqueous Extracts Research Articles

Synergistic antimicrobial activities of aqueous extract derived from olive byproduct and their modes of action

BackgroundPlant-derived antimicrobials (PDAs) are considered a viable alternative to synthetic antimicrobial agents. Diverse antimicrobial mechanisms of PDAs significantly reduce the risk of developing antimicrobial resistance. Utilization of PDAs also offers economic and environmental advantages, as they can be derived from agricultural byproducts, such as olive pomace.ResultsIn this study, a green, water-based, ultrasound-assisted extraction (UAE) was deployed to obtain aqueous olive pomace extract (OPE) from dry olive pomace. Total phenolic content, extraction yield, chemical compositions, and antimicrobial activities of OPE were evaluated. In addition, the potential synergistic interaction between the phenolic components in OPE and the antimicrobial mechanisms underlying the synergistic interaction were characterized. The results show that ca. 25 mg GAE/g of extraction yields were achieved by the UAE of dry olive pomace. Based on the high-performance liquid chromatography (HPLC) analysis, diverse phenolic compounds such as gallic acid (GA), hydroxytyrosol (HT), and 4-hydroxyphenylacetic acid (4-HPA) were identified in OPE. OPE exhibited strong antimicrobial activities, and 0.2 mg GAE/mL of OPE achieved > 5 log reductions of Escherichia coli O157:H7 and Listeria innocua cells within 30 min of treatment. A 3D isobologram analysis demonstrated that OPE exhibited strong synergistic antimicrobial activities, compared to those of individual phenolic components (GA, HT, or 4-HPA), showing interaction index (γ) of 0.092 and 0.014 against E. coli O157:H7 and L. innocua, respectively (γ < 1: synergistic activity). Antimicrobial mechanism analyses revealed that phenolic components in OPE exerted strong synergistic activities through diverse modes of action, and increased levels of oxidative stress, membrane damage, and decreased levels of metabolic activities were observed in the OPE-treated bacterial cells.ConclusionsThese findings demonstrate an approach for valorizing agricultural byproducts to develop plant byproduct-based antimicrobials with strong synergistic activities. Multiple modes of action of this byproduct extract may enable the control of diverse microbes in food and agriculture systems.Graphical abstract

Antimicrobial Activity of Leaf Aqueous Extract of Schinus polygamus (Cav.) Cabrera against Pathogenic Bacteria and Spoilage Yeasts.

The antimicrobial activity of an aqueous extract of the leaves of Schinus polygamus (cav.) Cabrera against microorganisms of food importance was evaluated. First, the leaf aqueous extract of Schinus polygamus was characterized, quantifying hydroxycinnamic acids and phenolic compounds. Then, a battery of strains was tested, including Escherichia coli ATCC 25922, Salmonella Typhimurium ATCC 14028, and Listeria monocytogenes ATCC 13932. Also, we tested wine spoilage yeasts such as Brettanomyces bruxellensis LAMAP2480, B. bruxellensis LAMAP1359, B. bruxellensis CECT1451, and Pichia guilliermondii NPCC1051. Tests were conducted using the kinetic curve of growth and cell viability counts. The results indicate that with 10% v/v of concentrated extract, it is possible to observe growth inhibition of all microorganisms studied, with statistically significant differences during the whole measurement time (70 h for bacteria and 145 h for yeast).

Anti-oxidant, anti-inflammatory and antimicrobial activity of aqueous extract from acerola and amla.

Amla, scientifically known as emblica officinalis and Acerola (malphigian emarginata) both are Vitamin C fruits possess varied medicinal properties being used for preventive disease health management strategies. Therefore, it is of interest to explore the antioxidant, anti-inflammatory, antibacterial, and cytotoxic properties of aqueous extracts from Acerola and Amla. Hence, the anti-inflammatory activity of Acerola and amla was assessed using the bovine serum albumin denaturation assay (BSA Assay), antioxidant properties were compared using DPPH (2,2-diphenyl-1-picrylhydrazyl) assay. Both extracts antibacterial activities were evaluated through the agar well diffusion technique against oral pathogens and Brine shrimp lethality assay for cytotoxicity. The current research sheds light on natural remedies for oxidative stress-related diseases, inflammatory conditions and bacterial infections, offering promising avenues for disease management and preventive healthcare strategies especially in the treatment of oral health diseases like periodontitis.

Antimicrobial activity of the aqueous extract of Acacia (Acacia nilotica) in inhibiting the growth of some pathogenic bacterial strains

The study was conducted in the laboratory of the Department of Biology at the College of Science and Arts in Baljurashi- Baha Region-Kingdom of Saudi Arabia. The aim of the research was studying the effectiveness of the aqueous extract of the Acacia plant Acacia Nilotica on the growth of some of pathogenic bacteria strains and comparing it with Myrrha essential oil (Commiphora Myrrha). The result indicated that the aqueous extract of the Acacia plant (Acacia Nilotica) has a potent antimicrobial activity against all tested organisms expect Pseudomonas spp. which showed resistance against it. The inhibitory level among all tested organisms (Stenotrophomona spp., Achromobacter spp., Shewa Nell spp., Pseudoxanthomas spp., Pseudomonas spp., Bacillus spp. were 14 , 28, 16, 20, 0 and 12 mm respectively. The highest antibacterial effect was against Achromobacter spp. where the inhibition zone (28mm) and the lowest antimicrobial effect was against Bacillus spp. where the inhibition zone (12mm). By the other hand Myrrha (Commiphora Myrrha) essential oil was very weak or did not cause any inhibition in the tested strains. More studies are needed to determine the antimicrobial activity of aqueous extract of the Acacia plant on other organisms which cause food spoilage, poisoning and food borne diseases.

Ethnopharmacological Survey, Phytochemical Screening and Antimicrobial Activities of Medicinal Plants Used in the Treatment of Diarrhea in Southeastern Gabon.

Diarrhea is a condition that particularly affects children under five the age of years old in developing countries. The aim of this study was to evaluate the efficacy of medicinal extracts plants used in treatment and to characterize their inhibitory capacity in the growth of bacteria isolates in childhood diarrhea in the southeast region of Gabon. An ethnobotanical survey on the plants used in the treatment of diarrhea in southeastern Gabon was carried out and a phytochemical screening of the collected plants was performed. The antimicrobial activity of aqueous extracts was evaluated; 33 plant species were identified, representing 28 genera and 19 families. Bark (39.5%) was the most commonly used plant part, followed by powder formulations (28.9%). The preferred method of preparation and chewing (44.7%), together with drinking (36.8%), were the most prevalent modes of administration. Phytochemical screening showed a plethora of secondary metabolites (terpenoids, alkaloids and phenolic compounds), and a marked level of anti-diarrheal activity was found with Sida acuta and Santiria. ebo against Shigella spp. (16.22 ± 0.7 mm and 14.05 ± 1.4 mm) and Yersinia pestis (16.35 ± 0.5 mm and 15.51 ± 0.5 mm). The high diversity of secondary plant metabolites and their inhibitory ability against enteric pathogens would justify their use at the local level to treat diarrheal infections.

Probiotic growth-stimulating capacity and antimicrobial activities of aqueous extracts of Lentinus crinitus (L.) Fr (polyporales, basidiomycota)

Lentinus crinitus (L.) Fr is a wild macrofungus that is popular as antimicrobial and various biological activities. This study aims to determine the capacity growth stimulation of Lactobacillus paracasei and antimicrobial activity of aqueous extracts of L. crinitus obtained from wild basidiomata, mycelial biomass by liquid fermentation and spent mushroom substrate obtained by solid-state fermentation. The antimicrobial activity was investigated against bacterial and fungal pathogens and growth stimulation L. paracasei probiotic bacterium. The total carbohydrate and β-glucan contents of the extracts were determined using colorimetric analysis. The aqueous extracts obtained showed inhibition against Fusarium oxysporum., Penicillium sp., Rhizopus oryzae, Aspergillus niger, Escherichia coli and Salmonella typhimurium. The aqueous extract obtained from wild basidiomata, and mycelial biomass showed the highest percentage of stimulation of L. paracasei growth in 48 h. The extracts obtained from L. crinitus have antimicrobial potential and stimulating capacity of the probiotic Lactobacillus paracasei. Additionally, different biotechnological techniques such as liquid and solid-state fermentation can be used to obtain aqueous extracts.

Antimicrobial Activity of Psidium guajava Aqueous Extract against Sensitive and Resistant Bacterial Strains.

The inappropriate use of antimicrobials, along with environmental conditions, can lead to the emergence of resistant microorganisms. The use of phytopharmaceuticals and herbal medicines has a positive impact and represents a promising alternative. Psidium guajava extracts have been widely reported to have antimicrobial potential; however, studies reporting their activity against resistant bacterial strains are scarce. Because of the emerging resistance, the aim of this study was to analyze the antimicrobial capacity of the aqueous extract of guava leaves against wild-type and resistant bacterial strains. The aqueous extract obtained from the leaves of P. guajava was evaluated by HPLC for the content of total phenolics and tannins, antioxidant activity, and chemical composition. The antimicrobial activity of the extracts was analyzed by the disk diffusion and broth microdilution methods. The results of the chemical analysis of the extracts showed total phenolics content of 17.02 ± 6.87 mg/g of dry extract, total tannin content of 14.09 ± 1.20 mg of tannic acid equivalents/g of dry extract, and moderate antioxidant capacity with an EC50 value of 140 µg/mL. Flavonoids are the major compounds (rutin, hesperidin, and quercetin), followed by phenolic acids. Disk diffusion test results showed the presence of inhibition halos for Gram-positive bacteria (Staphylococcus aureus, sensitive and resistant; Staphylococcus pseudintermedius, sensitive and resistant; and Streptococcus spp., beta-hemolytic), while for Gram-negative bacteria (Escherichia coli, sensitive and resistant), there was no inhibition in the tested concentration range. The Minimal Inhibitory Concentration was 6.8 mg/mL for all Gram-positive strains evaluated. The present study demonstrated the antimicrobial activity of the aqueous extract of P. guajava against sensitive and resistant Gram-positive bacteria. The better antimicrobial activity found in the present study compared with previously reported activity should be highlighted and may be related to the higher concentration of total phenolics present in the tested extract. Moreover, the content of tannins found suggests a species with high quality that produces tannins. These new findings suggest an innovative profile regarding therapeutic resources that can be adopted to combat resistant microbial strains.

Evaluation of antibacterial activity against Burkholderia pseudomallei VTCC 70157 and cytotoxicity ofpomegranate (Punica granatum) aqueous extract

Melioidosis is a severe acute infectious disease caused by Burkholderia pseudomallei, especially high epidemiological risk factors in agricultural operations with people frequently exposed to soil or water sources containing this bacterium. In this study, the thermal and gastric stability of antimicrobial activity of aqueous extracts prepared from pomegranate (Punica granatum) against Burkholderia pseudomallei VTCC 70157 (NA23) was evaluated by agar plate diffusion, minimal inhibitory dilution (MID), and minimal bactericidal dilution (MBD) methods. Additionally, the cytotoxicity of aqueous extract to HEK293, HepG2, and HT29 cell lines was also studied. The results showed that aqueous extracts of different pomegranate parts had a high antibacterial activity with an antibacterial zone diameter in the range of 21-28 mm. MID and MBD values were under 1:256 and 1:128, respectively. At the extraction temperature of 100oC, antibacterial activities were significantly higher than those of 25 and 70oC. This study also demonstrated that the antibacterial activity of the extracts highly remained under simulated gastrointestinal conditionsexcept for the MID value of the twig extracts which was increased by two times. In addition, the extracts exhibited low cytotoxicity with the tested human cell lines, with ID50 values consistently being remarkably higher than the corresponding MID values. The study results suggest that aqueous extracts of pomegranate prepared by decoction according to traditional medicine might be effective through oral administration for the treatment of melioidosis.

Evaluation of antimicrobial activity of aqueous extract of Prosopis f arc ta pods

The present study has been designated lo evaluate the antimicrobial activity of aqueous extract of Prosopis farcta pods. The antimicrobial activity of the extract against five fungal strains and four bacterial strains were tested by using Agar Well Diffusion method and minimal inhibitory concentration MIC values. The results showed that aqueous extract of P.farcta had antifungal and antibacterial effects against all the tested microorganisms, wherease Nystatin failed to show any effect against C.cladosporides. Therefore, these results suggest that the aqueous extract of P. farcta possess compounds with antimicrobial properties which can be used as antimicrobial agents in new drugs for therapy ofmicrobiaJ diseases in human

IN SILICO AND IN VITRO ANTIMICROBIAL TESTING OF AQUEOUS EXTRACT OF Vernonia amygdalina AGAINST Escherichia coli ISOLATED FROM WISTAR RATS INFECTED WITH Trypanosoma congolense

The study was carried out to investigate the in silico and in vitro antimicrobial activity of Vernonia amygdalina aqueous extract (VAAE) against Escherichia coli on rats already infected with Trypanosoma congolense. Forty Wistar rats of 16 weeks old were used, and were randomly selected into six groups, where n = 5 in groups A, B, D, E and F; n = 15 in group C. Group A: uninfected-untreated; group B: uninfected-treated (500 mg/kgbwt VAAE); group C: infected-untreated; groups D: infected-treated (100 mg/kgbwt VAAE), E: infected-treated (300 mg/kgbwt (VAAE) and F: infected-treated (500 mg/kgbwt (VAAE). Using docking simulation, a number of phytochemicals were screened and identified in the VAAE used in the study. The findings have given an indication of in vitro antimicrobial activity of aqueous extract of Vernonia amygdalina leaves against Escherichia coli. Docking with topoisomerase iv (3FV5) revealed that 3 compounds (−8.5 to – 8.3 kcal/mol) with docking scores lower than the co-crystalized PBE (-6.1kcal/mol). The five topmost docked compounds including vernonioside A22, vernonioside A42, luteolin-7-rutinoside, vernonioside D2 and proline betaine (PBE) with the lowest docking scores exhibited the highest binding tendency with topoisomerase iv, upon interaction analysis. Residues involved in the intermolecular interaction include Asp69, Ile116, Ser117, Leu94, Gly73 Leu89, Arg93, Ile90, Glu46 and Val39 (h-bonds), Val118, Ile90, Met74, Gly73, Arg72, Pro75, Val39, Val165 and Tyr505 (π-π stacking interactions) and Glu46. Our findings revealed the stability of vernonioside A22, vernonioside A42, luteolin-7-rutinoside, vernonioside D2 and proline betaine (PBE) on the target topoisomerase iv in the target organism, which in support of the in vitro study has also shown that Vernonia amygdalina leaves have antimicrobial potential and as such be considered as a formidable source for the search for new drugs against bacteria.

Comparative study of phenolic profile, antioxidant and antimicrobial activities of aqueous extract of white and green tea.

The sole difference between white tea (WT) and green tea (GT) is the former that made only from the buds and young leaves of the Camelia sinensis plant, whilst the latter is made from matured tea leaves. The phytochemical profiles, phenolic compounds, antioxidant, and antimicrobial activity of two varieties of Camellia sinensis teas, white and green, were compared in this study. Total antioxidant capacity, reducing power, DPPH radical scavenging, and Fe+2 chelating activities were used to determine antioxidant activities in water extract of GT and WT. The largest level of phenolic content was discovered in WGTE compared with the lowest amount was found in WWTE (290.67mg/100g tea and 185.96mg/100g tea, respectively). Phenoilc acids (gallic, benzoic, chlorogenic, ellagic, and ρ-coumaric acids) and flavonoids (rutin and kampherol) were found in the two extracts. The findings of DPPH radical scavenging assays were 84.06 and 82.37% inhibition. In vitro antimicrobial activity was indicated that (WWTE and WGTE) had a high level of activity against Staphylococcus aureus, and gave negative activity against Salmonella typhimurium, and Aspergillus Niger. The WT and GT extracts are a great source of natural antioxidants with biological effects on human health.

Evaluation of Antimicrobial Activity of Aqueous Extract of "Ocimum Sanctum-Queen of Herb" on Dental Caries Microorganisms: An In Vitro Study.

AimTo evaluate the efficacy of three different concentrations of Ocimum sanctum aqueous extract against various caries causing microorganisms, Streptococcus mutans, Streptococcus mitis, Streptococcus sanguis, and Lactobacillus acidophilus.Materials and methodsAqueous extract of Ocimum sanctum was prepared by the cold extraction method. The extract was diluted with milli Q water, to obtain 3 different concentrations [2%, 3%, and 4%] of the extract. Glycerol 6%v/v and tween-80, 0.1%v/v were also added to get a stable suspension. About 0.2% chlorhexidine was used as a positive control and milli Q water was used as a negative control. The extract, along with the controls, was then subjected to microbiological investigation to determine which concentration among the three different concentrations of extract gave a wider inhibition zone against Streptococcus mutans, Streptococcus mitis, Streptococcus sanguis, and Lactobacillus acidophilus. The zones of inhibition were measured in millimeters.ResultsOcimum sanctum aqueous extract demonstrated maximum antimicrobial activity against microorganisms responsible for dental caries at the 4% concentration level although 3% and 2% were also effective. Maximum activity was seen against S. mutans and S. sanguis with 4% extract.ConclusionOcimum sanctum aqueous extract was effective against all caries causing the microorganisms.Clinical significanceDental caries is still a major oral disease in children which affects their quality of life. It is important to come up with an alternative oral hygiene aid which is easily available and with lesser side effects and maximum benefits by acting against caries causing microbes. Thus aqueous extract of commonly available tulsi is studied to know its effect on caries causing microorganisms.How to cite this articlePai KR, Pallavi LK, Bhat SS, et al. Evaluation of Antimicrobial Activity of Aqueous Extract of “Ocimum Sanctum-Queen of Herb” on Dental Caries Microorganisms: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(S-2):S176-S179.

Evaluate the efficacy of Antimicrobial activity of aqueous extract of Nigella sativa seeds powder on Staphylococcus aureus

In Siddha medicine system has been classified into Aga marunthu (Internal) and Pura marunthu (External) having 32 forms of medicines in each. The external remedies are very useful for topical ulcers, skin diseases like eczema, psoriasis bacterial and fungal infections. The purpose this study was Evaluate the efficacy of Antibacterial activity of aqueous extract of Nigella sativa seeds powder against Staphylococcus aureus by used disk diffusion method. The result has been evaluated as the diameter of the zone of inhibition of microbial growth showed that the different concentration (100%, 50%, 25%) of Nigella sativa seed powder’s aqueous extract more effective against Staphylococcus aureus. Mean value of the hot extract 100%, 50%, 25% respectively 12.19±1.91mm, 7.63±2.32 mm and 3.78±1.73mm and the mean value of Cold extract were 9.45±1.32mm, 4.21±0.92mm and 2.71±.64mm. Standard maintained 18mm of zone of inhibition .Among the hot and cold extract, 100% of hot extract was showed more significant affect against Staphylococcus aureus which was 12.19mm. Finally this study was concluded that the Nigella seeds powder can be used as an antibacterial agent.&#x0D; &#x0D; &#x0D;

In vitro evaluation of antimicrobial activity and measuring its antigenic specific immune response in mice model studies: Allium cepa

Allium cepa (onion; Liliaceae family), herbaceous annual plant and reported Sulphur based amino acids with many minerals including vitamins. Inspite of various medicinal uses of this plant as food and also showed various beneficial effects. The antimicrobial activity of aqueous extract from Allium cepa (onion bulb) was evaluated against bacterial strains using disc diffusion method. In contrast, inflammatory response or inhibition of T cell antigenic response was evaluated using typhoid vaccine and swine flu vaccine in Swiss mice. These studies were conducted according to ethical guidelines and determining T cell proliferation including estimation of cytokines from cell culture supernatant and also measuring its hemolytic activity. The results showed that aqueous extract show the highest inhibition rate against Pseudomonas aeruginosa and Salmonella enteritidis. In mice model studies, aqueous extract at higher doses showed inhibition in antigen specific T cell proliferation and also declining in the level of IFN-gamma production but enhancement in IL-4 production. In addition, aqueous extract at higher concentration does not showed any hemolytic activity. Overall, this study provides evidence for the presence of secondary metabolites in aqueous extract that probably interferes with bacterial growth (antimicrobial) and also declining in antigenic specific proliferation (i.e. anti-inflammatory) which would prevent and inhibit initiation and progression of many diseases.

"Evaluate the efficacy of Antimicrobial activity of aqueous extract of Nigella Sativa seeds powder on Staphylococcus Aureus"

"Evaluate the efficacy of Antimicrobial activity of aqueous extract of Nigella Sativa seeds powder on Staphylococcus Aureus"

Influence of extraction technique on nutrient content, antioxidant and antimicrobial activity of aqueous extracts of commercial apricot kernels

This paper presents the results of influence of extraction technique on phytochemical composition and biological activity of aqueous extracts of commercial apricot kernels. Three techniques were used for extraction: maceration, ultrasonic and Soxhlet extraction. The content of total phenols, flavonoids, bioelements, antioxidant and antimicrobial activity was analyzed in the extracts. Antioxidant activity was analyzed in vitro using DPPH and FRAP methods. Antimicrobial screening was performed by diffusion technique on reference strains from the ATCC collection. The content of total phenols and flavonoids is highest in extracts obtained by ultrasonic extraction and maceration. These techniques have proven to be the best for the extraction of macro and micronutrients. The aqueous extract obtained by maceration at 300 rpm for 3 hours showed a greater inhibitory effect against the tested microorganisms, compared to the extracts obtained by other techniques. The least efficient method of extracting bioactive components from apricot kernels is Soxhlet extraction, with the lowest dry extract yield of 5.5%.  Â

Screening for Phytochemicals and Antimicrobial Activity of Aqueous extract of Tridax procumbens

The plants are producing different types of secondary metabolites and are employed either indirectly or directly in the pharmaceutical industries. The chemical constituents of secondary metabolites improve the primary health and physiological activity in human systems. Tridax procumbens is belonging to Asteraceae family. T. procumbens is classified as a weed. In traditional medicine, the leaves, root, and stem of T. procumbens were used to treatment of stomach pain, diarrhoea, colds, inflammations, hepatopathies, bacterial and skin infections. The main objectives of present study were to screen the phytochemicals and antimicrobial activity of aqueous extract of weed plant (T. procumbens). The phytochemical screening was carried out using the stranded methods. The evaluation of antimicrobial activity for aqueous extract of T. procumbens was done by agar well diffusion method using bacterial and fungal pathogens such as Bacillus subtilis, Escherichia coli, Fusarium oxysporium and Trichoderma reesei. All the phytochemicals such as carbohydrates, phenolic groups, glycosides, tannin, alkaloids, saponin, flavonoids and steroids were present in the extract of T. procumbens and were confirmed by phytochemical analysis. The aqueous extract has not shown antibacterial and antifungal activity against tested pathogens. Other evaluation process is to be done on isolation of phytochemicals and chemical structure determination of bioactive compounds.

Antioxidant and Antimicrobial Activities of Aqueous Extract of the Yellow and White Sweet Spanish onion (Allium cepa L.) in Isfahan

Antioxidant and Antimicrobial Activities of Aqueous Extract of the Yellow and White Sweet Spanish onion (Allium cepa L.) in Isfahan

Evaluation of antimicrobial activity of aqueous extracts of Acalypha indica

Evaluation of antimicrobial activity of aqueous extracts of Acalypha indica

Antimicrobial Activity of Aqueous Extracts Acquired from the Seeds of Two Apples' Cultivars

The pathogenic resistance to many standing antimicrobial agents alarms the urgency to explore original agents especially those derived from a natural provenance for managing this issue. In this study, aqueous extracts were prepared from the seeds of two apples' cultivars, Granny Smith and Red Delicious apples. This preparation was performed via two styles, which are non-serial and serially sorted in the increasing polarity. For each style, the extraction was accomblished by three methods including microwave- and ultrasound- aiding extraction techniques, and kinetic maceration. The microbiological studies were conducted on these extracts utilizing four standard bacterial strains (Klebsiella pneumonia, Pseudomonas aeruginosa, Escherichia coli, and Haemophilus influenzae) and two standard fungal strains (Aspergillus niger and Candida albicans). These in vitro studies were carried out via a well-documented agar disc diffusion method using ciprofloxacin and nystatin as golden references. The results indicated that these extracts showed an acceptable antimicrobial activity against the test pathogens with a primacy to those extracts acquired from Red Delicious apple seeds. Also, the results revealed that the preferable extraction style was the non-serial one and the favoured technique was the ultrasound-aiding extraction. It is concluded that these aqueous extracts may be useful as antimicrobial preparations with the possibility of their application as a home remedy for local bacterial and fungal infections.