Antifungal activity and detailed chemical characterization of Cistus ladanifer phenolic extracts

Abstract

The life-threatening mycoses caused by opportunistic fungal pathogens (mainly species from the genus Candida) associated with nosocomial infections, are one of the major health problems in our days. Therefore, it is crucial to identify new compounds, especially natural ones, that are active against the most broaden spectrum of Candida species. Herein, a screening of the antifungal potential of a phenolic extract of Cistus ladanifer from Northeastern Portugal, against Candida species was performed. Furthermore, the extract was characterized by HPLC-DAD-ESI/MS. Phenolic acids and derivatives (3.96 mg/g extract), ellagic acid derivatives (30.34 mg/g extract), and flavonoids (4.15 mg/g extract), such as catechins, flavonols and flavones, were found in the sample. The most abundant group was ellagic acid derivatives in which punicalagin gallate, a derivative of punicalagin attached to gallic acid, was found in highest amount (15.99 ± 0.02 mg/g extract). These compounds (i.e., ellagitannins) could be related to the strong inhibition of C. albicans, C. glabrata and C. parapsilosis growth (MIC < 0.05 mg/ml). Moreover, the best antifungal activity was against C. glabrata, where the studied extract was able to cause at least 3 Log of reduction at concentrations below 0.05 mg/mL and a total growth inhibition at concentrations above 0.625 mg/mL.

Antioxidant and Antimicrobial Properties of Cistus Ladanifer

“…The main part responsible for the antimicrobial capacity of Cistus plants seems to be the volatile fraction containing essentially terpenes, although relevant activity has been also reported for the polyphenolic fraction [6]. Our results revealed the presence of volatile components in Cistus sp.…”

Antifungal Activity of Phenolic Compounds Identified in Flowers from North Eastern Portugal Against Candida Species

“…With over 9000 natural antimicrobials identified, the flavonoid family is the largest group of phenolic compounds [30]. It is important to emphasize that the phenolic compounds used in this study, gallic acid (phenolic acid), catechin (flavan-3-ols), luteolin (flavone) and quercetin (flavonol), were previously identified in different medicinal flower species [24][25][26].…”

“…The extraction, identification and quantification of phenolic compounds from flowers of Castanea sativa, Filipendula ulmaria, Rosa micrantha [24] and Cytisus multiflorus [25], and fresh leaves of Cistus ladanifer [26] were previously described by the authors using a high-performance liquid chromatography-diode array detector/electrospray source mass spectrometer. This work was focused on four different phenolic compounds that seemed more promising against Candida species: one phenolic acid (gallic acid) and three flavonoids (catechin, luteolin and quercetin).…”

Phenolic quantification and botanical origin of Portuguese propolis

“…For C. ladanifer exudates, phenolic acids and esters were not detected at all using this experimental approach. This class of compounds is unusual in C. ladanifer, and in the literature only vanillic acid has been described at low concentrations in the methanol: water (80:20) extract of fresh leaves (Barros et al, 2013).…”