Antibacterial and antioxidative properties of different parts of garden rhubarb, blackcurrant, chokeberry and blue honeysuckle

Abstract

BACKGROUND: It is important to find plant materials that can inhibit the growth of Listeria monocytogenes and other food-spoiling bacteria both in vitro and in situ. The aim of the study was to compare antibacterial and antioxidative activity of selected plant-ethanol infusions: leaves and berries of blackcurrant (Ribes nigrum L.), berries of chokeberry (Aronia melanocarpa (Michx.) Elliott) and blue honeysuckle (Lonicera caerulea L. var. edulis); petioles and dark and light roots of garden rhubarb (Rheum rhaponticum L.) for potential use in food matrices as antibacterial and antioxidative additives. RESULTS: The strongest bacterial growth inhibition was observed in 96% ethanol infusions of the dark roots of rhubarbs. In 96% ethanol, nine out of ten studied plant infusions had antibacterial effect against L. monocytogenes, but in 20% ethanol only the infusions of dark rhubarb roots had a similar effect. Chokeberry and other berries had the highest antioxidative activity, both in 20% and 96% ethanol infusions. CONCLUSION: The combination of dark rhubarb roots or petioles and berries of black chokeberry, blackcurrant or some other anthocyanin-rich berries would have potential as both antibacterial and antioxidative additives in food.

Antimicrobial and Antioxidative Effects of Plant Powders in Raw and Cooked Minced Pork

“…The higher TOC values in the samples treated with BCleaves, tomato, and BHSberries can also be explained by LA oxylipins originating from blackcurrant leaves or tomato seeds [34] and cuticles, rich in unsaturated fatty acids, particularly linoleic acid. Compared to chokeberry and blackcurrant berries, blue honeysuckle berries do not contain delphinidin [13], which possesses a slightly higher antioxidant activity than cyanidin, owing to the presence of vicinal OH groups [35]. Altogether, tomato, rhubarb petioles, and blue honeysuckle berries exerted a pro-oxidative effect in meat mixtures (high TOC and MDA values, Figure 5A,C).…”

“…In this study, BCleaves had no inhibitory effect on microbial growth. Our previous in vitro study [13] found that petioles and the roots of garden rhubarb had a high antibacterial and antioxidative activity and suggested them as good candidates to use in meat products. Obviously, not always the promising results of in vitro studies are repeatable in food matrices.…”

“…In the raw samples, where enzymatic and chemical mechanisms are intertwined, GA, NaCl+NaNO 2 , Rutin, Rroot+CBberries, and Rroot+BCberries appeared to be the most effective inhibitors that guaranteed lower TOC levels compared to the control throughout the entire storage period, ( Figure 5A). The last two blends contained potent free-radical scavengers (anthocyanins) from the berries [30], as well as a number of antioxidants (polyphenols) from rhubarb root, like hydroxystilbenes, piceatannol glucoside, and galloglycosides of piceatannol, resveratrol, rhapontigenin, and deoxyrhapontigenin, as well as resveratrol dimers [13,15,31]. Flavonoids are known to inhibit oxidation chain initiation and prevent chain propagation through metal chelation or free-radical scavenging mechanisms, whereas phenolic acids act as antioxidants via free-radical trapping mechanisms [32].…”

“…For example, polyphenols can possess variable antioxidant effects depending on the possibility of synergic behavior when mixed [12]. Since berries and tomatoes are consumed without peeling, we can assimilate all useful compounds that are mainly located in their skin or underneath tissues.In the course of our in vitro experiments [13], seven plant powders were selected for further studies with meat matrices. Blackcurrant berries (Ribes nigrum L.) are known for their high content of vitamin C, phenolic acids, anthocyanins, and other flavonoids.…”

“…In the course of our in vitro experiments [13], seven plant powders were selected for further studies with meat matrices. Blackcurrant berries (Ribes nigrum L.) are known for their high content of vitamin C, phenolic acids, anthocyanins, and other flavonoids.…”