Antimicrobial activity of grape, apple and pitahaya residue extracts after carbohydrase treatment against food-related bacteria
Introduction
Foodborne diseases frequently occur worldwide. Salmonellosis and listeriosis are well-known infections but Staphylococcus aureus and certain Escherichia coli strains can also be associated with foodborne outbreaks (Callejón et al., 2015). These bacteria can form biofilm, that is, communities enclosed in self-synthesized polymer matrices, attached to biotic or abiotic surfaces. Within the biofilm, the cells are metabolically less active than the planktonic form, therefore, they are significantly less sensitive to the action of antimicrobial agents, which is the main cause of chronic infections (Landini, Antoniani, Burgess, & Nijland, 2010). Formation of biofilms is a complex process and depends on different cellular mechanisms. One of these is the population dependent cell-to-cell communication system, namely quorum sensing, that regulates additional cellular functions such as virulence gene expression, sporulation, conjugation, exopolysaccharide production and toxin production as well (Deep, Chaudhary, & Gupta, 2011). By quorum sensing inhibitors, biofilm formation of foodborne pathogenic and spoilage bacteria could also be inhibited (Kalia, 2013).
Recently, many synthetic antimicrobials are used successfully for shelf life extension, however, the consumers' growing concern against such preservatives in foods encourages researchers to screen and enrich the natural alternatives (Gyawali & Ibrahim, 2014). Polyphenols, e.g., phenolic acids, flavan-3-ols, flavonols and tannins, are intensively studied in this regard because of their ability to suppress various microbial virulence factors including those that are regulated by the quorum sensing system (Asfour, 2018; Brackman & Coenye, 2015; Slobodníková, Fialová, Rendeková, Kováč, & Mučaji, 2016). Furthermore, they are potent free radical scavengers and metal chelators. Thus, they can inhibit the lipid peroxidation and exhibit various additional physiological activities as antioxidants and antimicrobials (Daglia, 2012). Therefore, these kinds of phytochemicals are widely used in the food preservative developments as potential antimicrobial agents against various food-related pathogens (Papuc, Goran, Predescu, Nicorescu, & Stefan, 2017).
Grapes, apple and pitahaya (also known as dragon fruit) are promising sources of phenolic compounds. Besides the usable part of the fruits, by-products generated during the fruit processing are also rich in bioactive phenolics (Dembitsky et al., 2011; Kalinowska, Bielawska, Lewandowska-Siwkiewicz, Priebe, & Lewandowski, 2014; Teixeira et al., 2014). In a recent study, we successfully produced antioxidative phenolic-enriched extracts from oven-dried and lyophilized black grape, apple and pitahaya residues by direct enzymatic treatment using a cellulolytic cocktail from the zygomycete fungus Rhizomucor miehei NRRL 5282 and a pectinase from Aspergillus niger (Zambrano et al., 2018). The substrate pretreatment (oven-drying and lyophilization) affected the phenolic yield and the antioxidant activity. Furthermore, some extracts exhibited significant increase in the concentration of 4-hydroxybenzoic acid, syringic acid, gallic acid, vanillic acid, cinnamic acid, p-coumaric acid, (+)-catechin, (−)-epicatechin, quercetin, polydatin and resveratrol compounds. Here, the potential bioactive properties, i.e. the antimicrobial and anti-biofilm forming activities against five Gram-positive and four Gram-negative foodborne pathogen and food spoilage bacteria, and the anti-quorum sensing capacity of the extracts were investigated before and after enzymatic treatments. Furthermore, pure form of the previously examined individual phenolics was also subjected to bioactivity tests to study the possible correlation between the activity changes in the extracts and the increase in the phenolic compound concentrations after the enzymatic treatments.
Although antimicrobial capacity of various grape, apple and pitahaya cultivars has been investigated (Teixeira et al., 2014; Yadav, Kumar, Kumar, & Mishra, 2015; Zhang et al., 2016), there are only scarce data about yellow pitahaya residue samples (Choo, Koh, & Ling, 2016). Furthermore, the present assay provides useful information on the less studied Othello grape and Jonagold apple variants as potential sources of antimicrobial compounds.
Section snippets
Bacterial strains and growth conditions
Five Gram-positive bacteria, i.e. Bacillus subtilis (SZMC 0209), Bacillus cereus (SZMC 0042), Listeria monocytogenes (SZMC 21307), Staphylococcus aureus (SZMC 0579) and methicillin-resistant Staphylococcus aureus (MRSA, SZMC 6270) and four Gram-negative bacteria, i.e. Escherichia coli (SZMC 0582), Salmonella enterica subsp. enterica serovar Typhimurium ATCC 13311 (SZMC 23289), Pseudomonas putida (SZMC 6010) and Pseudomonas aeruginosa (SZMC 0568) were involved to the antimicrobial and
Screening assay on solid medium
In this assay, antimicrobial activity of enzyme-free and treated fruit extracts and individual phenolics against selected foodborne pathogens and spoilage bacteria was screened and compared by using a disk-diffusion method. Majority of the fruit residue extracts inhibited the growth of the bacteria studied (Table 1). Overall, B. subtilis, S. aureus and S. enterica proved to be the most sensitive to all extracts investigated. The lowest growth inhibition effect was detected towards L.
Conclusions
This study demonstrates the antimicrobial, anti-quorum sensing and anti-biofilm forming properties of phenolic-enriched extracts and individual phenolics produced from black grape, apple and pitahaya residues using R. miehei cellulase and A. niger pectinase cocktails alone or in combination. Disk-diffusion screening tests revealed growth inhibitory potential for the extracts against most foodborne pathogens and spoilage bacteria involved. Depending on the bacteria tested, antimicrobial activity
Acknowledgments
This work was supported by the Hungarian Government and the European Union within the frames of the Széchenyi 2020 Programme through grants EFOP-3.6.1-16-2016-00008 and GINOP-2.3.3-15-2016-00006. C.Z. thanks Tempus Foundation for Stipendium Hungaricum scholarship. T.P. is granted by the HAS “Momentum” project LP2016-8/2016. Research of M.T. was supported by the János Bolyai Research Scholarship of the Hungarian Academy of Sciences.
References (47)
- et al.
Effect of extraction solvent, waste fraction and grape variety on the antimicrobial and antioxidant activities of extracts from wine residue from cool climate
Food Chemistry
(2012) Polyphenols as antimicrobial agents
Current Opinion in Biotechnology
(2012)- et al.
The multiple nutrition properties of some exotic fruits: Biological activity and active metabolites
Food Research International
(2011) - et al.
Phytochemistry and activity against digestive pathogens of grape (Vitis vinifera L.) stem's (poly)phenolic extracts
LWT-Food Science and Technology
(2015) - et al.
Natural products as antimicrobial agents
Food Control
(2014) Quorum sensing inhibitors: An overview
Biotechnology Advances
(2013)- et al.
Apples: Content of phenolic compounds vs. variety, part of apple and cultivation model, extraction of phenolic compounds, biological properties
Plant Physiology and Biochemistry
(2014) - et al.
Inhibitory effects of flavonoids on biofilm formation by Staphylococcus aureus that over expresses efflux protein genes
Microbial Pathogenesis
(2017) - et al.
Antimicrobial activity and composition profile of grape (Vitis vinifera) pomace extracts obtained by supercritical fluids
Journal of Biotechnology
(2013) - et al.
Inhibitory effects of grape seed extract on growth, quorum sensing, and virulence factors of CDC “top-six” non-O157 Shiga toxin producing E. coli
International Journal of Food Microbiology
(2016)
Dietary phytochemicals as quorum sensing inhibitors
Fitoterapia
Mobilization of phenolic antioxidants from grape, apple and pitahaya residues via solid state fungal fermentation and carbohydrase treatment
LWT-Food Science and Technology
Antiquorum sensing and antimicrobial activity of natural agents with potential use in food
Journal of Food Safety
Antimicrobial activity of phenolic compounds identified in wild mushrooms, SAR analysis and docking studies
Journal of Applied Microbiology
Anti-quorum sensing natural compounds
Journal of Microscopy and Ultrastructure
Bacillus subtilis biofilm induction by plant polysaccharides
Proceedings of the National Academy of Sciences of the United States of America
Evaluation of the effects of selected phytochemicals on quorum sensing inhibition and in vitro cytotoxicity
Biofouling
Quorum sensing inhibitors as anti-biofilm agents
Current Pharmaceutical Design
Reported foodborne outbreaks due to fresh produce in the United States and European Union: Trends and causes
Foodborne Pathogens and Disease
Medicinal properties of pitaya: A review
Spatula DD
Inhibition of bacterial quorum sensing by vanilla extract
Letters in Applied Microbiology
Quorum sensing and bacterial pathogenicity: From molecules to disease
Journal of Laboratory Physicians
Anti-quorum sensing potential of antioxidant quercetin and resveratrol
Brazilian Archives of Biology and Technology
Cited by (34)
Absorbent bioactive aerogels based on germinated wheat starch and grape skin extract
2023, International Journal of Biological MacromoleculesAntimicrobial properties of papaya (Vasconcellea pubescens) subjected to low-temperature vacuum dehydration
2021, Innovative Food Science and Emerging TechnologiesCitation Excerpt :Nowadays, the consumers' growing concern against food preservatives has prompted the search for natural alternatives to synthetic antimicrobials in the food industry (Zambrano et al., 2019).
Potential application of grape (Vitis vinifera L.) stem extracts in the cosmetic and pharmaceutical industries: Valorization of a by-product
2020, Industrial Crops and ProductsCitation Excerpt :Other by-products (skins, seeds, pomace) also demonstrated antimicrobial capacity, inhibiting the growth of different L.monocytogenes, S. aureus, E. faecalis, and E. coli strains (Butkhup et al., 2010; Corrales et al., 2010; Zambrano et al., 2019). The antimicrobial potential of each extract/by-product may depend on the extraction method, the microorganism tested (Zambrano et al., 2019), and its polyphenolic content (Baenas et al., 2018). The antimicrobial activity of grape stem extracts was also evaluated by the Minimum Inhibitory Concentration assay, being the results presented in Table 4.