scholarly journals Characterization of Polyphenols, Flavonoids and Their Anti-microbial Activity in the Fruits of Vangueria madagascariensis J. F. Gmel

Author(s):  
Peter K. Njenga ◽  
Samuel M. Mugo ◽  
Ting Zhou

Aim: The study aimed to characterize phenolic acids, flavonoids, and determine their antimicrobial activities in fruits of Vangueria madagascariensis (Tamarind of Indies). Study Design: The design of the study included picking of Vangueria madagascariensis fruits from Jomo Kenyatta University of Agriculture and Technology (JKUAT) botanical garden and analysis for their antimicrobial activities at the Botany department research laboratory, JKUAT. Characterization of phenolic acids and flavonoids were conducted at MacEwan University Canada. Place and Duration: JKUAT, Kenya and MacEwan University, Edmonton, Alberta Canada between June 2013 and June 2016. Methodology: Phenolic acids and flavonoids from Tamarind of Indies were determined by high-performance liquid chromatography coupled with photodiode array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-ESI-MSN). The antimicrobial assay was determined using the disk diffusion method. Results: Based on the retention time, the UV spectrum, and the tandem MS behavior, the results revealed a profile composed of 25 phenolic compounds. Some of the identified phenolic compounds included: 3-caffeoylquinic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid, 4-feruloyl quinic acid, quercetin 3-O-galactoside, quercetin 3-O-glucoside, quercetin, 3,4-di-caffeoylquinic acid, 4, 5-di-caffeoylquinic acid, kaempferol, diosmetin, caffeic acid, epicatechin, kaempferol 3-O-glucoside. The fruit extracts had a probable presence of quercetin 3-O-6’-malonylglucoside, ikarisoside C, epimedin C, unknown epigallocatechin-3-gallate and quercetin conjugate derivatives. Furthermore, the fruit extracts from Vangueria madagascariensis showed appreciable antimicrobial properties against human pathogen strains. Strong antimicrobial activity was observed for Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans. The Vangueria madagascariensis was found to be highly potent against Escherichia coli and Bacillus subtilis even at low concentrations of 0.1 mg/mL. Conclusion: The research findings may suggest value of the use of Vangueria madagascariensis fruits as a rich source of antioxidants with therapeutic and nutraceutical value.

1970 ◽  
Vol 16 (12) ◽  
pp. 1285-1291 ◽  
Author(s):  
W. J. Peters ◽  
R. A. J. Warren

A variety of phenolic compounds and hydroxamic acids reduced or prevented phenolic acid and coproporphyrin accumulation by iron-deficient cultures of Bacillus subtilis, but only if they were added to cultures with levels of iron which alone did not prevent accumulation. The compounds also increased iron uptake by iron-deficient cultures and norma) cultures. When radioactive catechol or 2,3-dihydroxybenzoic acid was used to increase iron uptake by iron-deficient cells, only very low levels of radioactivity remained associated with the cells. It is suggested that B. subtilis produces phenolic acids to solubilize iron; that other phenolic compounds or hydroxamic acids may substitute for the phenolic acids produced by B. subtilis; that the iron: phenolic acid complex does not enter the cell; and that the iron is removed from the complex at the cell surface and taken into the cell by an energy-dependent active transport system.


2021 ◽  
Vol 50 (2) ◽  
pp. 219-226
Author(s):  
Abdul Haq ◽  
Alam Khan ◽  
Zulfiqar Ali Malik ◽  
Mushtaq Ahmed ◽  
Samiullah Khan ◽  
...  

Antimicrobial activities of deoiled seed kernel (mechanically pressed), fruit coat and seed coat of Jatropha curcas Linn. collected from two regions (Bannu and Peshawar) of Pakistan were investigated. The antimicrobial activities were carried out against Klebsiella pneumoniae (ATCC 43816), Escherichia coli (ATCC 10536), Staphylococcus aureus (ATCC 6538), Bacillus subtilis (ATCC 6633) and two clinical fungal isolates Aspergillus fumigatus and Candida albicans using agar well diffusion method. The antibacterial activities of Peshawar sample were found to be higher than Bannu, against selected strains. While antifungal activities of both samples were similar. Highest zone of inhibition 31.5 ± 0.7 mm was exhibited by n-hexane extract of deoiled seed kernel of Peshawar sample against Bacillus subtilis (ATCC 6633). The minimum inhibitory concentration of ethanolic extracts of deoiled seed kernel and seed coat of Peshawar sample was 31.25 - 25 mg/ml. Whereas, minimum inhibitory concentration of ethanolic and n-hexane extracts of Bannu sample was 62.5 - 125 mg/ml. The results suggested that antimicrobial potential of J. curcas Linn. varied with geographical distribution. The investigation of different varieties of medicinal plants belonging to the same species will greatly enhance the chances of best pharmaceuticals discovery. Bangladesh J. Bot. 50(2): 219-226, 2021 (June)


2019 ◽  
Vol 201 (20) ◽  
Author(s):  
Charles T. Lauhon

ABSTRACT In bacteria, tRNAs that decode 4-fold degenerate family codons and have uridine at position 34 of the anticodon are typically modified with either 5-methoxyuridine (mo5U) or 5-methoxycarbonylmethoxyuridine (mcmo5U). These modifications are critical for extended recognition of some codons at the wobble position. Whereas the alkylation steps of these modifications have been described, genes required for the hydroxylation of U34 to give 5-hydroxyuridine (ho5U) remain unknown. Here, a number of genes in Escherichia coli and Bacillus subtilis are identified that are required for wild-type (wt) levels of ho5U. The yrrMNO operon is identified in B. subtilis as important for the biosynthesis of ho5U. Both yrrN and yrrO are homologs to peptidase U32 family genes, which includes the rlhA gene required for ho5C synthesis in E. coli. Deletion of either yrrN or yrrO, or both, gives a 50% reduction in mo5U tRNA levels. In E. coli, yegQ was found to be the only one of four peptidase U32 genes involved in ho5U synthesis. Interestingly, this mutant shows the same 50% reduction in (m)cmo5U as that observed for mo5U in the B. subtilis mutants. By analyzing the genomic context of yegQ homologs, the ferredoxin YfhL is shown to be required for ho5U synthesis in E. coli to the same extent as yegQ. Additional genes required for Fe-S biosynthesis and biosynthesis of prephenate give the same 50% reduction in modification. Together, these data suggest that ho5U biosynthesis in bacteria is similar to that of ho5C, but additional genes and substrates are required for complete modification. IMPORTANCE Modified nucleotides in tRNA serve to optimize both its structure and function for accurate translation of the genetic code. The biosynthesis of these modifications has been fertile ground for uncovering unique biochemistry and metabolism in cells. In this work, genes that are required for a novel anaerobic hydroxylation of uridine at the wobble position of some tRNAs are identified in both Bacillus subtilis and Escherichia coli. These genes code for Fe-S cluster proteins, and their deletion reduces the levels of the hydroxyuridine by 50% in both organisms. Additional genes required for Fe-S cluster and prephenate biosynthesis and a previously described ferredoxin gene all display a similar reduction in hydroxyuridine levels, suggesting that still other genes are required for the modification.


2021 ◽  
Vol 3 (2) ◽  
pp. 124-126
Author(s):  
Jhon Patar Sinurat ◽  
Suci Wulandari ◽  
Rinaldo Berutu

Phytochemical screening test proved that the extract of Reeds (Imperata cylindrica) contained phenolic compounds tested using 5% FeCl3 reagent. Antibacterial test using agar diffusion method against Reeds extract in DMSO solvent. The phenolic compounds obtained from the saputangan leaves Reeds extract were 36.96 grams after undergoing maceration. Reeds extract of phenolic compounds with concentrations (200; 100; 50 and 25 ppm) had strength antibacterial where the average inhibition zone of Staphylococcus aureus bacteria was 10.0 mm and the average inhibition zone was at Escherichia coli bacteria measuring 10.3 mm.


Foods ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1206 ◽  
Author(s):  
Hafiz A. R. Suleria ◽  
Colin J. Barrow ◽  
Frank R. Dunshea

Fruit peels have a diverse range of phytochemicals including carotenoids, vitamins, dietary fibres, and phenolic compounds, some with remarkable antioxidant properties. Nevertheless, the comprehensive screening and characterization of the complex array of phenolic compounds in different fruit peels is limited. This study aimed to determine the polyphenol content and their antioxidant potential in twenty different fruit peel samples in an ethanolic extraction, including their comprehensive characterization and quantification using the LC-MS/MS and HPLC. The obtained results showed that the mango peel exhibited the highest phenolic content for TPC (27.51 ± 0.63 mg GAE/g) and TFC (1.75 ± 0.08 mg QE/g), while the TTC (9.01 ± 0.20 mg CE/g) was slightly higher in the avocado peel than mango peel (8.99 ± 0.13 mg CE/g). In terms of antioxidant potential, the grapefruit peel had the highest radical scavenging capacities for the DPPH (9.17 ± 0.19 mg AAE/g), ABTS (10.79 ± 0.56 mg AAE/g), ferric reducing capacity in FRAP (9.22 ± 0.25 mg AA/g), and total antioxidant capacity, TAC (8.77 ± 0.34 mg AAE/g) compared to other fruit peel samples. The application of LC-ESI-QTOF-MS/MS tentatively identified and characterized a total of 176 phenolics, including phenolic acids (49), flavonoids (86), lignans (11), stilbene (5) and other polyphenols (25) in all twenty peel samples. From HPLC-PDA quantification, the mango peel sample showed significantly higher phenolic content, particularly for phenolic acids (gallic acid, 14.5 ± 0.4 mg/g) and flavonoids (quercetin, 11.9 ± 0.4 mg/g), as compared to other fruit peel samples. These results highlight the importance of fruit peels as a potential source of polyphenols. This study provides supportive information for the utilization of different phenolic rich fruit peels as ingredients in food, feed, and nutraceutical products.


Author(s):  
Kokkaiah Irulandi ◽  
Sethupandian Geetha ◽  
Palanichamy Mehalingam

Objective: To determine antimicrobial activity of methanol, ethyl acetate and acetone extracts of Myristica fatua, Alstonia boonei, Helicteres isora, Vitex altissima and Atalantia racemosa  against different species of pathogens, Streptococcus feacalis, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Bacillus subtilis, Staphyllococcus aureus, and Candida albicans.Methods: Antimicrobial activity of plant extracts was measured by agar well diffusion method.Results: Acetone extracts of Alstonia boonei showed the highest inhibitory effect against Escherichia coli (21.00 ± 1.00 mm) and Streptococcus faecalis (19.00 ± 1.00 mm). All the extracts of Heliteres isora leaves showed different zone of inhibition observed in all the tested pathogens ranges between (8.13 ± 1.53 – 15.25 ± 1.23 mm). Ethyl acetate extract of Vitex altissima showed highest activity against Bacillus sublilis (19.67 ± 1.53 mm). Methanol and acetone leaves extracts of Atalantia racemosa have good fungal activity against the Candida albicans (19.33 ± 1.26 mm - 16.00 ± 1.00 mm). Methanol extract of Myristica fatua showed high antimicrobial activity against Pseudomonas aeruginosa (15.10 ± 0.17 mm) and Bacillus subtilis (14.23 ± 0.21 mm).Conclusion: The results from the study suggest that the leaves Myristica fatua, Alstonia boonei, Helicteres isora, Vitex altissima and Atalantia racemosa showed good antimicrobial activity against the different pathogens. They are used as the alternative source for the control and treatment of microbial infections.Keywords: Antimicrobial activity, Leaves extracts,  Well diffusion method, Pathogenic strains.


BMC Genomics ◽  
2007 ◽  
Vol 8 (1) ◽  
Author(s):  
Shujiro Okuda ◽  
Shuichi Kawashima ◽  
Kazuo Kobayashi ◽  
Naotake Ogasawara ◽  
Minoru Kanehisa ◽  
...  

2013 ◽  
Vol 41 (1) ◽  
pp. 126 ◽  
Author(s):  
Hossam S. EL-BELTAGI ◽  
Mona H. BADAWI

The widespread use of medicinal plants for health purposes has increased dramatically due to their great importance to the public health. In this study levels of phenolic, flavonoid contents of Ginkgo biloba and Rosmarinus officinalis from Egypt were determined. HPLC was used to identify and quantify the phenolic compounds in selected plants. The plant extracts were evaluated for their antioxidant activities using various antioxidant methodologies, (i) scavenging of free radicals using 2, 2-diphenyl-1-picrylhydrazyl, (ii) metal ion chelating capacity, and (iii) scavenging of superoxide anion radical. The antimicrobial activity of both plant’s extracts were evaluated against a panel of microorganisms by using agar disc diffusion method. The total phenolic content (75.30 and 98.31 mg/g dry weight in G. biloba and R. officinalis, respectively) was significantly (p<0.05) different. Among the identified phenolic compounds, quercetin, kaempferol and caffeic acid were the predominant phenolic compounds in Ginkgo biloba, whereas carnosic acid, rosmarinic acid, narinigen and hispidulin were the predominant phenolic compound in Rosmarinus officinalis leaves. The antioxidant activity increased with the concentration increase. The R. officinalis was more active than G. biloba extract against Gram-negative bacteria. This study reveals that the consumption of these plants would exert several beneficial effects by virtue of their antioxidant and antimicrobial activities.


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