Antimicrobial activity and chemical profile of wood vinegar from eucalyptus (Eucalyptus urophylla x Eucalyptus grandis - clone I144) and bamboo (Bambusa vulgaris)

Bamboo vinegar powder: Unveiling its antioxidant and antifungal efficacy through bioactive compound analysis and mechanistic insights

Bamboo vinegar has been applied in livestock and fisheries as food additives. In this study, the antioxidant and antifungal properties of bamboo vinegar powder extract (BVPE) and its bioactive compounds were explored. BVPE exhibited significant free radical scavenging activity against DPPH and ABTS radicals, along with notable antifungal effects against Aspergillus terreus and Paecilomyces variotii. LC-MS/MS analysis identified several bioactive compounds, including 1,2,3-trihydroxybenzene, 4-methylcatechol, 3,4-dihydroxyhydrocinnamic acid, and hydroquinone, exhibiting strong antioxidant capacities. Moreover, eight abundant compounds revealed significant antifungal activity, with 4-methylcatechol and 4-methylbenzoic acid displaying potent effects. Notably, 4-methylbenzoic acid, with low cytotoxicity, was assessed for its antifungal mechanism through RNA-seq analysis, suggesting involvement of the shikimate pathway. Molecular docking analysis indicated that 4-methylbenzoic acid could potentially disrupt the shikimate pathway by interacting with key enzymes. Overall, BVPE holds promise as a natural antioxidant and antifungal agent, with particular emphasis on the potential therapeutic role of 4-methylbenzoic acid.

Mechanistic Investigation of the Pyrolysis Temperature of Reed Wood Vinegar for Maximising the Antibacterial Activity of Escherichia coli and Its Inhibitory Activity

To solve the problem of large-scale growth of wetland reeds, wood vinegar, a by-product of pyrolysed reed wood vinegar, can be used as a natural antimicrobial agent. In this study, we compare the changes in growth and bacterial morphology of Escherichia coli (E. coli) treated with reed wood vinegar at different pyrolysis temperatures (300 °C, 500 °C and 700 °C) and reveal the bacterial inhibition mechanism of reed wood vinegar by RNA-Seq. The results of bacteria inhibitory activity showed that 1/2MIC 500 °C wood vinegar had the most prominent bacteria inhibitory activity. qPCR results showed that reed wood vinegar was able to significantly inhibit the expression of E. coli biofilm and genes related to the cell membrane transporter proteins. Electron microscopy observed that the wood vinegar disrupted the cellular morphology of E. coli, resulting in the crumpling of E. coli cell membranes. RNA-Seq showed the multifaceted antimicrobial effects of wood vinegar and demonstrated that the inhibitory effect of wood vinegar on E. coli was mainly realized through the inhibition of the expression of malE, which is an ATP-binding cassette (ABC) transporter complex of E. coli. In conclusion, our study provides an effective method and a theoretical basis for the mechanism of reed wood vinegar as a natural antimicrobial agent and its pathway of bacterial inhibition.

Antimicrobial Impact of Wood Vinegar Produced Through Co-Pyrolysis of Eucalyptus Wood and Aromatic Herbs

BACKGROUND

The search for substances that can overcome microorganisms' resistance and enhance the antimicrobial activity of given products has attracted the attention of researchers. Eucalyptus wood vinegar (WV) is a promising product for developing alternative antimicrobials.

OBJECTIVES

This study aimed to evaluate whether the production of WV in the co-pyrolysis of eucalyptus wood with aromatic herbs would incorporate compounds from them into WV and if that would enhance its antimicrobial action.

METHODOLOGY

WV was produced alone and through co-pyrolysis with marjoram (Origanum majorana), Peruvian oregano (Origanum vulgare), rosemary (Salvia rosmarinus), thyme (Thymus vulgaris), and Turkish oregano (Origanum onites) at a proportion of 25% of herbs to the bone-dry wood weight. The antimicrobial effects were assessed against strains of gram-negative and -positive bacteria, and Candida glabrata. Microorganisms' colony growth in agar had their absorbances recorded after inoculation and incubation. Chemical characterization of the new products was performed by gas chromatography and mass spectrometry (GC/MS).

RESULTS

After coproduction, there were relevant chemical changes concerning the original WV. Thymol, for instance, was incorporated into the WV through co-pyrolysis with marjoram, Peruvian and Turkish oregano, and thyme. The coproducts were more efficient than the WV produced only with wood, with thyme-incorporated products having the highest efficiency. This can be attributed to the increase and incorporation of the substances after coproduction, and particularly the role of thymol in enhancing the antimicrobial action.

CONCLUSION

Given the results, the co-production of WV with eucalyptus wood and aromatic herbs has the potential to provide alternative antimicrobial products.

Wood Distillate Interactions with Urea in Soil: A First Step to Developing a Slow-Release Next-Generation Fertilizer

We tested the ability of wood distillate (WD) to interact with urea in agricultural soil. WD is a sustainable material that has been addressed as a promising alternative to synthetic soil corroborants. However, there is little information about the effect of WD on the nitrogen cycle. In this study, soils with different amounts of WD and with/without urea were tested for ammonium, urease, nitrate/nitrite, and potential nitrification activity at different points in a 30 day time frame. High concentrations of WD (1-2%) inhibited the hydrolysis of urea and the oxidation of ammonium to nitrate. Thermal desorption coupled to GC-MS and high-performance liquid chromatography-tandem mass spectrometry characterization allowed us to reveal that WD-urea interactions mainly involve lignin-derived compounds in the distillate, such as catechol, resorcinol, and syringol. This study provides the first evidence of a strong interaction between WD and urea in soil that could be used to develop slow-release fertilizers.

The Potential of Wood Vinegar to Replace Antimicrobials Used in Animal Husbandry-A Review

The indiscriminate use of antimicrobials in animal husbandry can result in various types of environmental contamination. Part of the dose of these products is excreted, still active, in the animals' feces and urine. These excreta are widely used as organic fertilizers, which results in contamination with antimicrobial molecules. The impacts can occur in several compartments, such as soil, groundwater, and surface watercourses. Also, contamination by antimicrobials fed or administrated to pigs, chickens, and cattle can reach the meat, milk, and other animal products, which calls into question the sustainability of using these products as part of eco-friendly practices. Therefore, a search for alternative natural products is required to replace the conventional antimicrobials currently used in animal husbandry, aiming to mitigate environmental contamination. We thus carried out a review addressing this issue, highlighting wood vinegar (WV), also known as pyroligneous acid, as an alternative antimicrobial with good potential to replace conventional products. In this regard, many studies have demonstrated that WV is a promising product. WV is a nontoxic additive widely employed in the food industry to impart a smoked flavor to foods. Studies have shown that, depending on the WV concentration, good results can be achieved using it as an antimicrobial against pathogenic bacteria and fungi and a valuable growth promoter for poultry and pigs.