title: HPLC-UV and LC-MS Analyses of Acylquinic Acids in Geigeria alata (DC) Oliv. & Hiern. and their Contribution to Antioxidant and Antimicrobial Capacity.
abstract: BACKGROUND
  Geigeria alata is a traditional plant used in Sudanese folk medicine for treatment of diabetes, cough, epilepsy and intestinal complaints.
  
  
  OBJECTIVE
  To analyze phenolic acids in Geigeria alata roots and leaves and to evaluate their antioxidant and antimicrobial activities.
  
  
  METHODS
  Phenolic acids in the aqueous-methanol extracts were identified by LC-MS. Major compounds were isolated using low-pressure liquid chromatography. The quantitative analysis of phenolic acids was performed by a validated HPLC-UV method with limits of detection ranging from 0.04 to 0.57 μg/mL. 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azinobis-(3-ethylbenzothiazine-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) methods were used for antioxidant activity evaluation. In addition, the minimal inhibitory concentration and the minimal bactericidal concentration against a panel of pathogenic bacteria and fungi were determined by the broth microdilution test.
  
  
  RESULTS
  For the first time protocatechuic, caffeic, p-coumaroylquinic, caffeoylsinapoylquinic, caffeoylferuloylquinic, three feruloylquinic, six caffeoylquinic acids, and a caffeic acid hexoside were detected in Geigeria alata roots by LC-MS. HPLC-UV analyses showed that 3,5-dicaffeoylquinic acid (25.96 ± 2.08 mg/g dry weight (DW)) was the most abundant phenolic acid in roots, while 4,5-dicaffeoylquinic acid (8.99 ± 0.56 mg/g DW) was the main compound present in leaves. 3,5-Dicaffeoylquinic acid demonstrated stronger radical scavenging activity and reducing power compared with the crude extracts and the positive control 5-caffeoylquinic acid. 3,4,5-Tricaffeoylquinic acid revealed the highest antibacterial potential against the penicillin sensitive and resistant Staphylococcus aureus strains, as well as methicillin-resistant S. aureus.
  
  
  CONCLUSIONS
  The caffeoylquinic acids content of up to 6.22% in Geigeria alata roots establishes this species as a new source rich in these bioactive molecules. Copyright © 2016 John Wiley & Sons, Ltd.
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Sofia, 2, Dunav str., 1000, Sofia, Bulgaria.
authors.forename: Dimitrina
authors.initials: D
authors.lastname: Zheleva-Dimitrova
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Sofia, 2, Dunav str., 1000, Sofia, Bulgaria.
authors.forename: Reneta
authors.initials: R
authors.lastname: Gevrenova
authors.affiliation: Department of Infectious Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Akad. G. Bonchev Str., 1113, Sofia, Bulgaria.
authors.forename: Maya M
authors.initials: MM
authors.lastname: Zaharieva
authors.affiliation: Department of Infectious Microbiology, The Stephan Angeloff Institute of Microbiology, Bulgarian Academy of Sciences, 26 Akad. G. Bonchev Str., 1113, Sofia, Bulgaria.
authors.forename: Hristo
authors.initials: H
authors.lastname: Najdenski
authors.affiliation: Department of Medical Chemistry and Biochemistry, Medical University of Sofia, 2 Zdrave str., Sofia, 1431, Bulgaria.
authors.forename: Silviya
authors.initials: S
authors.lastname: Ruseva
authors.affiliation: Department of Medical Chemistry and Biochemistry, Medical University of Sofia, 2 Zdrave str., Sofia, 1431, Bulgaria.
authors.forename: Valentin
authors.initials: V
authors.lastname: Lozanov
authors.affiliation: Department of Pharmacognosy, Faculty of Pharmacy, Medical University of Sofia, 2, Dunav str., 1000, Sofia, Bulgaria.
authors.forename: Vessela
authors.initials: V
authors.lastname: Balabanova
authors.affiliation: Botany Department, Faculty of Science, University of Khartoum, Sudan.
authors.forename: Sakina
authors.initials: S
authors.lastname: Yagi
authors.affiliation: Department of Pharmacology, pharmacotherapy and toxicology, Faculty of Pharmacy, Medical University of Sofia, 2, Dunav Str., 1000, Sofia, Bulgaria.
authors.forename: Georgi
authors.initials: G
authors.lastname: Momekov
authors.affiliation: Department of Medical Chemistry and Biochemistry, Medical University of Sofia, 2 Zdrave str., Sofia, 1431, Bulgaria.
authors.forename: Vanio
authors.initials: V
authors.lastname: Mitev
mesh_terms: D000890:Anti-Infective Agents / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D000975:Antioxidants / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology*; D002109:Caffeic Acids / Q000032:analysis; D002726:Chlorogenic Acid / Q000031:analogs & derivatives / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002853:Chromatography, Liquid; D005419:Flavonoids / Q000032:analysis; D036621:Geigeria / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods; D055624:Methicillin-Resistant Staphylococcus aureus / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D018515:Plant Leaves / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry; D059808:Polyphenols / Q000032:analysis; D011801:Quinic Acid / Q000031:analogs & derivatives / Q000032:analysis
chemical_list: D000890:Anti-Infective Agents; D000975:Antioxidants; D002109:Caffeic Acids; D005419:Flavonoids; D010936:Plant Extracts; D059808:Polyphenols; C472707:caffeoylquinic acid; D011801:Quinic Acid; D002726:Chlorogenic Acid; C100434:3,5-dicaffeoylquinic acid; C040048:caffeic acid
keywords: Caffeoylquinic acids; Geigeria alata; HPLC-UV; LC-MS