Lactic acid fermentation as a tool to enhance the functional features of Echinacea spp

Abstract

BackgroundExtracts and products (roots and/or aerial parts) from Echinacea ssp. represent a profitable market sector for herbal medicines thanks to different functional features. Alkamides and polyacetylenes, phenols like caffeic acid and its derivatives, polysaccharides and glycoproteins are the main bioactive compounds of Echinacea spp. This study aimed at investigating the capacity of selected lactic acid bacteria to enhance the antimicrobial, antioxidant and immune-modulatory features of E. purpurea with the prospect of its application as functional food, dietary supplement or pharmaceutical preparation.ResultsEchinacea purpurea suspension (5%, wt/vol) in distilled water, containing 0.4% (wt/vol) yeast extract, was fermented with Lactobacillus plantarum POM1, 1MR20 or C2, previously selected from plant materials. Chemically acidified suspension, without bacterial inoculum, was used as the control to investigate functional features. Echinacea suspension fermented with Lb. plantarum C2 exhibited a marked antimicrobial activity towards Gram-positive and -negative bacteria. Compared to control, the water-soluble extract from Echinacea suspension fermented with Lactobacillus plantarum 1MR20 showed twice time higher radical scavenging activity on DPPH. Almost the same was found for the inhibition of oleic acid peroxidation. The methanol extract from Echinacea suspension had inherent antioxidant features but the activity of extract from the sample fermented with strain 1MR20 was the highest. The antioxidant activities were confirmed on Balb 3T3 mouse fibroblasts. Lactobacillus plantarum C2 and 1MR20 were used in association to ferment Echinacea suspension, and the water-soluble extract was subjected to ultra-filtration and purification through RP-FPLC. The antioxidant activity was distributed in a large number of fractions and proportional to the peptide concentration. The antimicrobial activity was detected only in one fraction, further subjected to nano-LC-ESI-MS/MS. A mixture of eight peptides was identified, corresponding to fragments of plantaricins PlnH or PlnG. Treatments with fermented Echinacea suspension exerted immune-modulatory effects on Caco-2 cells. The fermentation with Lb. plantarum 1MR20 or with the association between strains C2 and 1MR20 had the highest effect on the expression of TNF-α gene.ConclusionsE. purpurea subjected to lactic acid fermentation could be suitable for novel applications as functional food dietary supplements or pharmaceutical preparations.

Quorum-Sensing Regulation of Constitutive Plantaricin by Lactobacillus plantarum Strains under a Model System for Vegetables and Fruits

“…Domains, located in the N-terminal proteolytic region of PlnG, are responsible for recognition and cleavage of the double-glycine leader peptides from precursors of various bacteriocins, such as the plantaricins J/K (17,26,57). Similar peptides were also found in the antimicrobial extract of Echinacea sp., which was also fermented with L. plantarum C2 (58). The MIC of the purified fraction, which contained the mixture of the identified peptides, was comparable to the MIC values previously reported for partially purified antimicrobial peptides produced by lactic acid bacteria (58,72).…”

“…Similar peptides were also found in the antimicrobial extract of Echinacea sp., which was also fermented with L. plantarum C2 (58). The MIC of the purified fraction, which contained the mixture of the identified peptides, was comparable to the MIC values previously reported for partially purified antimicrobial peptides produced by lactic acid bacteria (58,72). To the best of our knowledge, the antimicrobial activity of plantaricins J/K toward the Gram-negative E. coli was not found previously.…”

“…The antimicrobial activity of L. plantarum C2 was the most intense. Recently, this strain was used as a functional starter to ferment an Echinacea suspension, which exhibited a marked antimicrobial activity toward Gram-positive and -negative bacteria (58). The antimicrobial activity of L. plantarum strains was assayed on vegetable and fruit agar plates (solid conditions) and juices (liquid conditions), which mimicked food-like conditions.…”

Obtención, caracterización y evaluación de dos preparados candidatos a probióticos desarrollados con residuos agroindustriales

“…Subsequently, the dishes were incubated at 37°C for 48 h. After the formation of visible colonies, 10 mL of BBL culture medium (212207 -BD BBL™ Enterococcosel™, EEUU) were poured on the dishes, which contained 0.01 mL of the indicator pathogen strain with a concentration of 9.2x10⁷ UFC/mL and then were incubated at 37°C for 48 h. The antagonist activity was verified for the formation of transparent zones around the colonies greater than 1.0 mm. In order to verify the nature of the inhibition the described technique of Rizzello et al (13) was performed.…”

Effect of Lactic Acid Fermentation on Total Phenolic Content and Antioxidant Activity of Fig Fruit Juice (Ficus carica)

“…(Rizzello & Coda 2013), and Malaysian herbal teas (Ibrahim, Mustafa & Ismail 2014). It was also reported that parts of plants experiencing the increase of total phenolic content after the fermentation (Ng et al 2014).…”