DOI: 10.1007/s00449-023-02921-1
Given the mounting concerns surrounding conventional chemical preservatives and their potential effects on human health and the environment, numerous companies have been actively seeking safe and environmentally friendly alternatives.
Among various production methodologies, enzymatic bioprocessing boasts numerous advantages that align with eco-friendly initiatives within industries. These advantages include reduced generation of undesirable by-products, enhanced selectivity, and specificity, lower energy consumption, and operation under mild reaction conditions, such as room temperature and atmospheric pressure. Consequently, enzymatic processes have garnered increasing attention from environmentally conscious and sustainable industries.
The research published in Bioprocess and Biosystems Engineering endeavoured to create effective and safe preservatives from plant sources. To achieve this, authors explored a novel approach involving solvent-free lipase-catalyzed transesterification, specifically targeting the conversion of vanillyl alcohol with ethyl propionate. This biocatalytic conversion facilitated the transformation of vanillyl alcohol into its short-chain ester via the acylation of its alcohol group using lipase (EC 3.1.1.3) as a green biocatalyst. Crucially, this enzymatic acylation process was executed without the need for added solvents, minimizing its environmental impact. Ethyl propionate, a natural substance found in certain fruits was selected, as the acyl donor. This solvent-free enzymatic synthesis holds significant promise as it mitigates environmental concerns, reduces additional costs, and can yield the highest achievable product concentration, ultimately resulting in impressive productivities. Following synthesis, the vanillyl propionate was purified and its antimicrobial and antioxidant properties were assessed in comparison to propyl paraben. Furthermore, its impact on human cells in terms of toxicity was investigated.
Unlike vanillyl alcohol and ethyl propionate, vanillyl propionate demonstrated noteworthy antimicrobial activity. A minimal inhibitory concentration test revealed that it displayed potent and broad-spectrum antimicrobial efficacy against a variety of microorganisms, including Gram-negative and Gram-positive bacteria, yeasts, and molds. This antimicrobial activity was on par with that of propyl paraben, known for its effectiveness as a preservative. In addition, vanillyl propionate exhibited superior antioxidant capacity and exhibited high biocompatibility with human cells when compared to propyl paraben.
This plant-derived preservative, produced through an environmentally friendly bioprocess, holds great promise for diverse industries due to its robust antimicrobial and antioxidant properties, as well as its high biocompatibility. Additionally, the lipophilic nature of vanillyl propionate can address the limited solubility issues associated with vanillyl alcohol, enhancing its potential applications across various industries.
Of particular interest is the heightened biocompatibility of vanillyl propionate compared to propyl paraben, despite their structural similarities. It appears that this enhanced biocompatibility may be attributed to vanillyl propionate’s antioxidant activity, a quality not shared by parabens, which have been associated with decreased skin cell viability, oxidative stress, and mitochondrial dysfunction.
