title: Structure-Activity Relationships of Antimicrobial Gallic Acid Derivatives from Pomegranate and Acacia Fruit Extracts against Potato Bacterial Wilt Pathogen.
abstract: Bacterial wilts of potato, tomato, pepper, and or eggplant caused by Ralstonia solanacearum are among the most serious plant diseases worldwide. In this study, the issue of developing bactericidal agents from natural sources against R. solanacearum derived from plant extracts was addressed. Extracts prepared from 25 plant species with antiseptic relevance in Egyptian folk medicine were screened for their antimicrobial properties against the potato pathogen R. solancearum by using the disc-zone inhibition assay and microtitre plate dilution method. Plants exhibiting notable antimicrobial activities against the tested pathogen include extracts from Acacia arabica and Punica granatum. Bioactivity-guided fractionation of A. arabica and P. granatum resulted in the isolation of bioactive compounds 3,5-dihydroxy-4-methoxybenzoic acid and gallic acid, in addition to epicatechin. All isolates displayed significant antimicrobial activities against R. solanacearum (MIC values 0.5-9 mg/ml), with 3,5-dihydroxy-4-methoxybenzoic acid being the most effective one with a MIC value of 0.47 mg/ml. We further performed a structure-activity relationship (SAR) study for the inhibition of R. solanacearum growth by ten natural, structurally related benzoic acids.
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El Aini st., P. B. 11562, Cairo, Egypt (phone: +20-2-23632245; fax: +20-2-25320005). mfarag@ipb-halle.de, mfarag73@yahoo.com.|Leibniz Institute of Plant Biochemistry, Dept. Bioorganic Chemistry, Weinberg 3, DE-06120 Halle (Saale). mfarag@ipb-halle.de, mfarag73@yahoo.com.
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Farag
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El Aini st., P. B. 11562, Cairo, Egypt (phone: +20-2-23632245; fax: +20-2-25320005).
authors.forename: Dalia A
authors.initials: DA
authors.lastname: Al-Mahdy
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El Aini st., P. B. 11562, Cairo, Egypt (phone: +20-2-23632245; fax: +20-2-25320005).
authors.forename: Riham
authors.initials: R
authors.lastname: Salah El Dine
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El Aini st., P. B. 11562, Cairo, Egypt (phone: +20-2-23632245; fax: +20-2-25320005).
authors.forename: Sherifa
authors.initials: S
authors.lastname: Fahmy
authors.affiliation: Microbiology Department, Faculty of Pharmacy, Cairo University, Kasr El Aini st., P. B. 11562, Cairo, Egypt.
authors.forename: Aymen
authors.initials: A
authors.lastname: Yassin
authors.affiliation: Leibniz Institute of Plant Biochemistry, Dept. Bioorganic Chemistry, Weinberg 3, DE-06120 Halle (Saale).
authors.forename: Andrea
authors.initials: A
authors.lastname: Porzel
authors.affiliation: Pharmacognosy Department, Faculty of Pharmacy, Cairo University, Kasr El Aini st., P. B. 11562, Cairo, Egypt (phone: +20-2-23632245; fax: +20-2-25320005).
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Brandt
mesh_terms: D000045:Acacia / Q000737:chemistry*; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D005638:Fruit / Q000737:chemistry; D005707:Gallic Acid / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D029561:Lythraceae / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D043368:Ralstonia solanacearum / Q000187:drug effects* / Q000254:growth & development; D013329:Structure-Activity Relationship
chemical_list: D000900:Anti-Bacterial Agents; D010936:Plant Extracts; D005707:Gallic Acid
keywords: Acacia arabica; Punica granatum; Ralstonia solanacearum; Structureactivity relationships (SAR)