title: Quantitative analysis of rutin, quercetin, naringenin, and gallic acid by validated RP- and NP-HPTLC methods for quality control of anti-HBV active extract of Guiera senegalensis.
abstract: BACKGROUND
  Guiera senegalensis J.F. Gmel (Combretaceae) is a folk medicinal plant used in various metabolic and infectious diseases. In addition to its antiviral activities against herpes and fowlpox, the anti-HBV efficacy is very recently reported.
  
  
  OBJECTIVE
  To develop and validate simple, sensitive RP-/NP-HPTLC methods for quantitative determination of biomarkers rutin, quercetin, naringenin, and gallic acid in the anti-HBV active G. senegalensis leaves ethanol-extract.
  
  
  METHODS
  RP-HPTLC (rutin & quercetin; phase- acetonitrile:water, 4:6) and NP-HPTLC (naringenin & gallic acid; phase- toluene:ethyl acetate:formic acid, 6:4:0.8) were performed on glass-backed silica gel plates 60F254-RP18 and 60F254, respectively. The methods were validated according to the ICH guidelines.
  
  
  RESULTS
  Well-separated and compact spots (Rf) of rutin (0.52 ± 0.006), quercetin (0.23 ± 0.005), naringenin (0.56 ± 0.009) and gallic acid (0.28 ± 0.006) were detected. The regression equations (Y) were 12.434x + 443.49, 10.08x + 216.85, 11.253x + 973.52 and 11.082x + 446.41 whereas the coefficient correlations (r2) were 0.997 ± 0.0004, 0.9982 ± 0.0001, 0.9974 ± 0.0004 and 0.9981 ± 0.0001, respectively. The linearity ranges (ng/spot) were 200-1400 (RP-HPTLC) and 100-1200 (NP-HPTLC). The LOD/LOQ (ng/band) were 33.03/100.1 (rutin), 9.67/29.31 (quercetin), 35.574/107.8 (naringenin), and 12.32/37.35 (gallic acid). Gallic acid (7.01 μg/mg) was the most abundant biomarker compared to rutin (2.42 μg/mg), quercetin (1.53 μg/mg) and naringenin (0.14 μg/mg) in the extract.
  
  
  CONCLUSIONS
  The validated NP-/RP-HPTLC methods were simple, accurate, and sensitive for separating and quantifying antiviral biomarkers in G. senegalensis, and endorsed its anti-HBV activity. The developed methods could be further employed in the standardization and quality-control of herbal formulations.
authors.affiliation: a Department of Pharmacognosy, College of Pharmacy , King Saud University , Riyadh , Saudi Arabia.
authors.forename: Perwez
authors.initials: P
authors.lastname: Alam
authors.affiliation: a Department of Pharmacognosy, College of Pharmacy , King Saud University , Riyadh , Saudi Arabia.
authors.forename: Mohammad K
authors.initials: MK
authors.lastname: Parvez
authors.affiliation: a Department of Pharmacognosy, College of Pharmacy , King Saud University , Riyadh , Saudi Arabia.|b Department of Pharmacognosy, College of Pharmacy , Omdurman Islamic University , Khartoum , Sudan.
authors.forename: Ahmed H
authors.initials: AH
authors.lastname: Arbab
authors.affiliation: a Department of Pharmacognosy, College of Pharmacy , King Saud University , Riyadh , Saudi Arabia.
authors.forename: Mohammed S
authors.initials: MS
authors.lastname: Al-Dosari
mesh_terms: D000998:Antiviral Agents / Q000032:analysis*; D002855:Chromatography, Thin Layer / Q000379:methods; D029764:Combretaceae; D044950:Flavanones / Q000032:analysis*; D005707:Gallic Acid / Q000032:analysis*; D006515:Hepatitis B virus; D010936:Plant Extracts / Q000032:analysis; D018515:Plant Leaves; D011794:Quercetin / Q000032:analysis*; D012431:Rutin / Q000032:analysis*
chemical_list: D000998:Antiviral Agents; D044950:Flavanones; D010936:Plant Extracts; D012431:Rutin; D005707:Gallic Acid; D011794:Quercetin; C005273:naringenin
keywords: Natural products; antiviral; combretaceae; flavonoids; plant extract; polyphenols