Antibacterial and Antifungal Properties of Acetonic Extract ofFeijoa sellowianaFruits and Its Effect onHelicobacter pyloriGrowth

Abstract

Feijoa sellowiana Berg. fruit, widely used for human consumption, is well appreciated for its good nutritional characteristics and for its pleasant flavor and aroma. In a prior study we showed that the acetonic extract of F. sellowiana fruit exerts a potent antibacterial activity against some Gram-positive and Gram-negative bacterial strains. To confirm and deepen the study on antimicrobial activities of the fruit, in this article we analyze the same extract for its effectiveness against different kind of bacteria both as American Type Culture Collection standard strains and clinically isolates, the Gram-negative Helicobacter pylori, and three fungal strains (one human pathogen and two phytopathogens). Our aim was also to isolate and define the active component(s) involved in the antibacterial, antifungal, and anti-H. pylori activity of the extract through activity-guided fractionation procedures. This allowed us to identify flavone as the active compound of F. sellowiana fruit. Flavone showed a high antibacterial activity against the nine standard bacterial strains tested and the matched clinically isolated bacterial strains and was significantly more active against H. pylori than metronidazole. Pseudomonas aeruginosa, Proteus mirabilis, and Proteus vulgaris from both standard and clinical sources showed a very high sensitivity to flavone (minimal inhibitory concentration [MIC] = 1.95 microg/mL for standard strains and 3.9 microg/mL for clinical isolates of the three bacteria), showing also good minimal bactericidal concentration values. Among fungi tested, Rhyzoctonia solani was the most sensitive strain to the action of flavone (MIC = 62.5 microg/mL).

Acetonic Extract from the Feijoa sellowiana Berg. Fruit Exerts Antioxidant Properties and Modulates Disaccharidases Activities in Human Intestinal Epithelial Cells

“…Extracts from the whole F . sellowiana fruit or its peel are described as possessing various biological properties, including a strong antimicrobial and antioxidant activity (Basile et al ., ; Basile et al ., ; Vuotto et al ., ). In addition, the F .…”

“…sellowiana fresh fruits were treated with Triton X‐100/0.8% water solution to remove epiphytic hosts normally found on the surface. Fruit extraction was performed as elsewhere reported (Basile et al ., ). The extract was then centrifuged at 2800 × g , and the supernatant was oven‐dried at 45 °C.…”

Antimicrobial activity of natural products against Helicobacter pylori: a review

“…Burret. Myrtaceae Fruit Acetone Extract In vitro [ 34 ] Strychnos pseudoquina A. St. Hil. Loganiaceae Leaves Methanol extract/alkaloid enriched fraction In vitro and in vivo [ 35 ] Bixa orellana L. Bixaceae Seed Ethanol Extract In vitro [ 4 ] Chamomilla recutita L. Asteraceae Inflorescence Ethanol Extract In vitro [ 4 ] Ilex paraguariensis A. St.-Hil.…”

“…Basile et al [ 34 ] demonstrated in vitro that the acetone extract of the fruits of Feijoa sellowiana (Berg.) Burret.…”

Reversal of fluconazole resistance induced by a synergistic effect withAcca sellowianainCandida glabratastrains

“…Among these species, C. glabrata was the most sensitive to the fractions, with the lower MIC values. Basile et al (2010) observed antifungal activity against C. albicans strains (MIC value¼ 250 lg/mL) and filamentous fungi, however, with the acetone extract of the fruits of A. sellowiana. In a study conducted by Park et al (2006), it was verified that the epigallocatechin gallate (EGCg), derived from catechins, has lower MIC values that of FLZ and AND for seven Candida species.…”