Antioxidant and antimicrobial activities of fruit extracts from different fresh chili peppers

The aim of the current study was to assess the antimicrobial and antioxidant potential of ethanol extracts obtained from the fruit of five species of fresh chili pepper, Capsicum (C.) baccatum L. (Aji Amarillo), C. chinense (Fidalgo Roxa), C. annuum (Cherry Chocolate), C. pubescens (Rocoto Orange) and C. frutescens (Peruvian Purple).

To obtain the ethanol extracts, accelerated solvent extraction (ASE) was applied. DPPH assay was used to determine the antioxidant activity of the extract samples. The disc diffusion method was used to measure antimicrobial activity against nine investigated microorganism species.

The tested extract samples exhibited DPPH radical scavenging activities ranging from 0.24 ±0.01 (Peruvian Purple) to 0.72 ±0.02 (Aji Amarillo) mg TEAC∙g–1 dw. The differences between all the varieties were statistically significant (P < 0.05; except for the Cherry Chocolate and Rocoto Orange), and the potential of antioxidant capacity increased in the following manner: Peruvian Purple < Fidalgo Roxa < Rocoto Orange < Cherry Chocolate < Aji Amarillo. The results from the antimicrobial evaluation showed that the Capsicum extracts had no uniform inhibition activity against tested gram-negative, gram-positive bacteria, and yeast. Specifically, Aji Amarillo fruit extract revealed the strongest antimicrobial activity against S. pneumoniae (6.33 ±0.58 mm), followed by Cherry Chocolate against S. pneumoniae (5.33 ±0.58 mm), Rocoto Orange against S. enterica (5.27 ±0.58 mm), Fidalgo Roxa against C. albicans (4.67 ±0.58 mm), and Peruvian Purple against S. pneumoniae (4.57 ±0.58 mm).

Considering these results, Capsicum spp. can be used as a source of novel antioxidant and antimicrobial compounds.