How does benzoic acid work against microbes

The concentration of hydroxyl and methoxyl derivatives of benzoic acid had little effect on the amount of biofilm produced. Several studies confirm the stimulating effect of antibacterial compounds on biofilm formation at low concentrations. This effect is a defensive response of bacteria to stressful environmental conditions. Stimulation of biofilm formation by low concentrations was described under the influence of antibiotics [ 25 ], alcohol [ 26 ], and plant extracts [ 27 ].

Borges et al. Comparing the action of the examined phenolic acids with benzoic acid, it can be stated that the presence and number of additional groups in the structure increase the properties against biofilm formation.

The method of hierarchical cluster analysis was used to illustrate the effect of individual acids on E. Subgroups with short Euclidean distances are visible except 2hBa acid.

The main factor determining the influence of the examined acids on the inhibition of E. The most effective of the examined phenolic acids was 2hBa, characterized by the same bacteriostatic strength as Ba, but showing shorter time of E. Derivatives containing methoxyl substituents are more active in limiting biofilm formation.

It should be noted that the use of antibacterial compounds may provide prospects for reducing microbial hazards. Systems of such compounds can be the basis for application in many industrial branches such as antibacterial preparations. Antibacterial substances can also be an integral component of various polymers used in the production of packaging e.

These substances can be added by coating the surface with the active ingredient as well as in the process of extruding polymers. However, we believe that further research should be continued in this scientific direction. Conflict of interest: The authors declare no conflict of interest. This fact did not affect the peer-review process. Sustainable production of natural phenolics for functional food applications. J Funct Food. Search in Google Scholar. Antimicrobials in Food. ISBN Synthesis and antimicrobial activities of novel sorbic and benzoic acid amide derivatives.

Food Chem. Synergistic anti-Campylobacter jejuni activity of fluoroquinolone and macrolide antibiotics with phenolic compounds. Front Microbiol. Synergistic interactions between phenolic compounds identified in grape pomace extract with antibiotics of different classes against Staphylococcus aureus and Escherichia coli.

PLoS One. Inhibitory activity of phenolic acids against Listeria monocytogenes: deciphering the mechanisms of action using three different models. Food Microbiol. Evaluation of antimicrobial and antioxidant activities of natural phenolic compounds against foodborne pathogens and spoilage bacteria.

Food Control. Method for determining bactericidal activity of antimicrobial agents: approved guide standard. Wayne, PA: Microtitre plate-based antibacterial assay incorporating resazurin as an indicator of cell growth, and its application in the in vitro antibacterial screening of phytochemicals.

Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically approved standard. Diag Micr Infec Dis. Rutin inhibits mono and multi-species biofilm formation by foodborne resistant Escherichia coli and Staphylococcus aureus. Antimicrobial activity of phenolic acids against commensal, probiotic and pathogenic bacteria. Res Microbiol.

Antimicrobial activity of essential oils and structurally related synthetic food additives towards selected pathogenic and beneficial gut bacteria. J Appl Microbiol. Antimicrobial Activity of Selected Phytochemicals against Escherichia coli and Staphylococcus aureus and their biofilms.

Antibacterial spectrum of plant polyphenols and extracts depending upon hydroxyphenyl structure. Biol Pharm Bull. Combined effect of gallic acid and catechin against Escherichia coli. Antimicrobial activity of phenolic compounds identified in wild mushrooms, SAR analysis and docking studies. Multidrug resistance in hydrocarbon-tolerant Gram-positive and Gram-negative bacteria. Enhancement of Escherichia coli and Staphylococcus aureus antibiotic susceptibility using sesquiterpenoids. Med Chem. Antibacterial properties of polyphenols: characterization and qsar quantitative structure—activity relationship models.

Structure-affinity relationship of the binding of phenolic acids and their derivatives to bovine serum albumin. ATP requirements for benzoic acid tolerance in Zygosaccharomyces bailii. Stimulation of biofilm formation by antibiotics. Biofilm formation by Staphylococcus epidermidis depends on functional RsbU, an activator of the sigB operon: differential activation mechanisms due to ethanol and salt stress.

J Bacteriol Res. Bacillus subtilis biofilm induction by plant polysaccharides. Antibacterial activity and mode of action of ferulic and gallic acids against pathogenic bacteria. Optimum functionality occurs between 2. Benzoic acid is mostly used in coloured products of tomato,phalsa, jamun, pomegranate, strawberry, coloured grapes etc.

Sodium benzoate, sodium salt of benzoic acid, is very effective as it is nearly times more soluble in water than benzoic acid. It produces benzoic acid when dissolved in water. It should be used at low levels to avoid possible off-flavours in some products. The maximum level allowable by PFA act is 0. It is used in fruit products, jams, relishes, beverages etc. Sorbic acid and related compounds Sorbic acid and related compounds have antimicrobial properties. They are available as sorbic acid, potassium sorbate, sodium sorbate or calcium sorbate.

Salts of sorbic acid are used in many cases as they are highly soluble in water and produce sorbic acid when dissolved in water. Since the sequence of the first bacterial genome Haemophilus influenzae Rd was completed in [ 24 ], the quantity of microbial genomic data has exploded [ 25 ]. In biodegradation studies, complete genome sequences can be used to rapidly interpret strain characteristics and predict degradation mechanisms [ 26 , 27 ].

While some benzoic acid-degrading bacteria have been discovered, the large number of microbial resources warrants further exploration, and there is merit in studying the application of such microbes in bioremediation.

In this study, the benzoic acid-degrading strain Pseudomonas sp. SCB32 was isolated from Sanqi continuous cropping soils. The effects of substrate concentration, pH, and temperature on the biodegradation of benzoic acid by strain SCB32 were explored. The complete genome sequence of the strain SCB32 was determined, and degradation products of the strain were analyzed by gas chromatography-mass spectrometry GC-MS to determine the intermediate metabolites of benzoic acid.

A possible degradation pathway was deduced following the combined analysis of genome annotation and MS data. Moreover, the toxicity of degradation products of benzoic acid was measured to investigate potential applications of the strain. Isolating and identifying an efficient benzoic acid-degrading bacterial strain and exploring the mechanisms of degradation are of particular significance for the agricultural environment, as it potentially provides a new way to alleviate the problems associated with continuous cropping.

Benzoic acid All other chemical reagents were of analytical grade. Ultrapure water Bacterial strains that degraded benzoic acid in the culture were isolated and purified following the procedure described by Buermans and den Dunnen [ 26 ]. Bacteria were collected and washed with 0. All experiments were performed three times. Gram staining was performed according to the method described by Claus, and physiological and biochemical identification was accomplished using the VITEK GN test.

The closest reference sequences were then obtained from the GenBank database, and a phylogenetic tree was generated using MEGA 6. The initial series determined the concentration range, optimum pH, and temperature for benzoic acid degradation by selected strains. For all experiments, the preparation method of the test bacterial solution was the same as above, and a culture medium without bacteria was used as a control.

Ethyl acetate extracts were dried under nitrogen gas and then derivatized with N , O -bis trimethylsilyl trifluoroacetamide TMS. Separation was achieved on a VF-5ms column.

Seeds of lettuce Lactuca sativa L. Thirty seeds were placed in each dish, and each treatment was repeated three times. After 7 days, the germination rate and fresh weight were measured. All analyses were performed using SPSS v After 5 weeks of enrichment, domestication, and separation, four strains of benzoic acid-degrading bacteria were obtained from the soil samples. All four strains could grow in MSM with benzoic acid as the sole carbon source.

The isolates exhibited variable degradation capacity Strain SCB32 showed the greatest degradation ability and was therefore selected for further study. Cells of strain SCB32 were Gram stain-negative, rod-shaped, and 0. On the basis of these results, the isolate was designated Pseudomonas sp. Degradation of benzoic acid by strain SCB32 at different initial concentrations, temperatures, and pH is shown in Figure 3.

Temperature had a strong influence on the degradation rate. Soon after, cell concentration increased exponentially and benzoic acid was degraded. Approximately coding genes and 71 repeated sequences were predicted.

A graphical circular genome map of strain SCB32 is shown in Figure 5. Cellular components, molecular functions, and biological processes of strain SCB32 were also classified and revealed by genome functional annotation against the GO database.

According to KEGG pathway mapping, Among the predicted genes, 31 were associated with benzoic acid metabolism Supplementary Table S3. The benzoic acid degradation process was identified by GC-MS analysis. During the growth of the SCB32 cocultures with benzoate, three TMS derivatives of interest were detected during different stages of the degradation process. In sterile MSM cultures without inoculation of strain SCB32, benzoic acid changed little and no target metabolites were detected throughout the experiment.

These results indicate that benzoic acid degradation by strain SCB32 occurs through the ortho pathway. Benzoic acid may be hydroxylated to form catechol, which is subsequently oxidized by ring fission to yield cis , cis -muconic acid, followed by muconolactone, and ultimately, downstream products enter the citrate cycle TCA cycle.

The toxicity of benzoic acid and its degradation products were evaluated using lettuce seeds Figures 8 and 9. However, when the lettuce seeds were exposed to benzoic acid inoculated with strain SCB32, there was a significant detoxification effect. The degradation products of benzoic acid did not significantly inhibit seed germination rate, plant height, or fresh weight, which were 1. Interestingly, root length of the degradation product-treated group increased by 6.

Allelochemicals, metabolites produced by living organisms that have a detrimental effect on other species when released into the environment, significantly inhibit plant growth [ 11 , 37 ].

The use of microorganisms to degrade allelochemicals such as benzoic acid and for soil remediation has proven to be effective [ 38 , 39 ]. In this study, using an enrichment and domestication strategy, a benzoic acid-degrading bacterium, SCB32, was isolated and revealed to be a member of the genus Pseudomonas.

The genus Pseudomonas , belonging to the family Pseudomonadaceae , is metabolically diverse and contains more than species with validly published names [ 40 ]. The most closely related genus is Azomonas [ 41 ]. Modern bacterial taxonomy defines species by directly comparing whole genome sequences, and average nucleotide identity ANI has been widely recognized as a useful tool in this process [ 42 ]. Unfortunately, combined with the identification results of physiological, biochemical, and molecular biology analyses, the specific classification of strain SCB32 cannot currently be determined.

A more comprehensive identification of strain SCB32 will be conducted in future work. Many bacterial species from the genus Pseudomonas have been reported to degrade benzoic acid or benzoate, but their degradation ability varies. But above this concentration, an inhibitory effect was observed.

This is because benzoic acid has a known antibacterial effect [ 5 ]. For example, Pseudomonas sp. QTF5 can degrade For P. Compared with them, stain SCB32 has a higher degradation capacity. In addition, strain SCB32 shows better pH adaptability for benzoic acid degradation.

The benzoic acid degradation rate of strain SCB32 was reduced under specified temperature conditions, determined by the characteristics of the strain itself [ 29 ]. Although some environmental pollutants are degraded by microbes, they may produce toxic intermediates such as benzoic acid or catechol and cannot be further degraded [ 46 , 47 ].

Therefore, autotoxicity of the final degradation products of pollutants is of interest. Lettuce Lactuca sativa L. Strain SCB32 therefore has potential in the biodegradation of benzoic acid for agricultural applications.

The metabolic processes of most of the benzoic acid-degrading bacteria are based on presumed evidence, including the identification of metabolites and the detection of key enzyme activities [ 22 , 49 ], and inferring metabolism is an imperfect task.

In contrast, microbial genome analysis and gene annotation allowed us to directly display the various genes responsible for the biodegradation potential of benzoic acid [ 26 ], promoting investigation of environmental bioremediation by strain SCB In this study, the benzoic acid metabolic pathway based on genome annotation and MS was inferred Figure Initially, benzoic acid is converted into 1,2-dihydro-1,2-dihydroxybenzoic acid DHB by benzoate-1,2-dioxygenase benA-xylX , benB-xylY , or benC-xylZ gene , then transformed into catechol by the function of the gene benD-xylL [ 50 , 51 ].

Catechol is an intermediate of many aromatic metabolites [ 52 ]. Next, catechol, transformed into cis , cis -muconate, undergoes ring cleavage by catechol-1,2-dioxygenase catA gene through the ortho pathway [ 53 ]. Subsequently, the metabolites of each process undergo a series of transformations under functional genes such as catB , catC , and pcaD and finally degrade to tricarboxylic acid TCA cycle [ 54 , 55 ].

Moreover, using GC-MS analysis, catechol, cis , cis -muconic acid, and 3-oxoadipate were identified. This is consistent with the pathway based on genome prediction. Some intermediate metabolites were not detected, because they transformed either too fast or at a low level. For example, 1,2-dihydro-1,2-dihydroxybenzoic acid is a very unstable intermediate and is usually consumed rapidly [ 56 ]. Comprehensive understanding of the degradation mechanism may help with continued enhancement of the process of bioremediation.

Data obtained in this study indicate that strain SCB32 could degrade a model allelochemical benzoic acid as the sole carbon source for growth and that it could effectively degrade benzoic acid in MSM. Furthermore, the degradation products of benzoic acid by strain SCB32 had no obvious toxic effect on lettuce germination.

Our results provide the groundwork for further elucidation of the genetic basis of benzoic acid degradation in strain SCB These results indicate a possible application of strain SCB32 in the bioremediation of benzoic acid contamination in agricultural environments. The authors declare that there is no conflict of interest regarding the publication of this paper. Wei Xiang and Xiaolan Wei performed the experiments. Wei Xiang performed bacterial identifications and analyzed the genomic data.

All authors read and approved the final manuscript. AA and AA Table S2: average nucleotide identity ANI. Supplementary Materials. This is an open access article distributed under the Creative Commons Attribution License , which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Article of the Year Award: Outstanding research contributions of , as selected by our Chief Editors. Read the winning articles. Journal overview. Special Issues. Academic Editor: Shin-ichi Yokota. Received 23 Dec Accepted 17 Apr Published 03 Jul Abstract Allelochemicals are metabolites produced by living organisms that have a detrimental effect on other species when released into the environment.

Introduction Aromatic compounds, widely found in the environment as components of plant materials and as pollutants of anthropogenic sources, are usually toxic to cellular systems and must be removed [ 1 ].