Analysis of condensed and hydrolysable tannins from commercial plant extracts.
High performance liquid chromatography (HPLC)/DAD and MS qualitative and quantitative analyses of polyphenols, hydrolysable and condensed tannins from Pinus maritima L. and tannic acid (TA) extracts were performed using normal and reverse phase. Normal-phase HPLC was more suitable for pine bark (PBE) and tannic acid extracts analysis. The chromatographic profile revealed that P. maritima L. extract was mainly composed by polymeric flavanols (containing from two to seven units) and tannic acid (characterized by a mixture of glucose gallates containing from three to seven units of gallic acid). Concerning their antimycotic properties, P. maritima L. extract exhibited a broad activity towards yeast strains of the genera Candida, Cryptococcus, Filobasidiella, Issatchenkia, Saccharomyces: MICs from 200 to 4000 microg/ml (corresponding to 140-2800 microg/ml of active polyphenols) were determined. Conversely, no activity of tannic acid was observed over the same target microorganisms. Taken into consideration the above results of HPLC analysis and on the basis of the current literature, we may conclude that only 70.2% of polyphenols (recognized as condensed tannins) occurring in P. maritima L. extract can be apparently considered responsible for its antimycotic activity.
Romani
A
A
University of Florence, Department of Pharmaceutical Science, Via Ugo Schiff 6, I-50019 Sesto Fiorentino, Florence, Italy. annalisa.romani@unifi.it
Ieri
F
F
Turchetti
B
B
Mulinacci
N
N
Vincieri
F F
FF
Buzzini
P
P
D000935:Antifungal Agents / Q000737:chemistry* / Q000494:pharmacology; D002175:Candida / Q000187:drug effects / Q000254:growth & development; D002851:Chromatography, High Pressure Liquid; D003454:Cryptococcus / Q000187:drug effects / Q000254:growth & development; D047348:Hydrolyzable Tannins / Q000032:analysis*; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D028223:Pinus / Q000737:chemistry*; D024301:Plant Bark; D010936:Plant Extracts / Q000737:chemistry* / Q000494:pharmacology; D044945:Proanthocyanidins / Q000032:analysis*; D012440:Saccharomyces / Q000187:drug effects / Q000254:growth & development; D013634:Tannins / Q000737:chemistry* / Q000494:pharmacology; D013997:Time Factors
D000935:Antifungal Agents; D047348:Hydrolyzable Tannins; D010936:Plant Extracts; D044945:Proanthocyanidins; D013634:Tannins