There is a global need for new antimicrobials. With the rise of antimicrobial resistance and the overuse and abuse of antiseptics, preservatives, and antibiotics there is a growing likelihood that the next pandemic may be a microbial one.
In today's world, the average person can find antibacterial and or anti fungal compounds in almost all of their daily products. Cosmetics, surfaces in the home, and especially food are all at risk o contamination and ultimately overgrowth of microbes. This puts us at risk of potentially life-threatening infections by methicillin resistant Staphyloccocus aureus (MRSA), Candida albicans (yeast infection), and Escherichia coli. While our fear of these microscopic killers entices us to increase the use of preservatives and antiseptics, we now know this is not helpful as it gives microbes repeated opportunities to mutate into something that will be resistant to these products.
Currently the most popular preservatives and antiseptic drugs are single compound synthetic chemicals. According to Deza et al, the most common preservatives are isothiazolinones, methyldibromo glutaronitrile (MDBGN), parabens, iodopropynyl butylcarbamate (IPBC), formaldehyde and the formaldehyde-releasers. Preservatives such as Phenoxyethanol or formaldehyde actually have natural origins but are now synthetically re-created to meet commercial needs and make it easier for managing and regulations.
As single compound drugs however they provide only one form of protection. Alcohol based preservatives, for example, denature the membrane holding bacteria together, rupturing it and consequently killing the microbe. Isothiazolinones take a different approach by inhibiting enzyme function of microbes required for their survival. When microbes are exposed to one or the other, separately and frequently, they can mutate in a way to overcome this preservative and deem it ineffective.
We already see something like this happening with MRSA. This can cause life-threatening conditions and has been found to be resistant to even the newest antibiotic drugs such as linezolid, vancomycin, teicoplanin, and daptomycin. Single compound drugs and preservatives are showing their weakness, we need a new way of preventing microbial infections. In order to do this we can take a cue from the movement back toward natural products and once again take inspiration from plants.
Plants, being the chemical factories that they are, take a highly complicated approach toward antimicrobial. After all, plants cannot run away from their "dirty" environments or sanitize every leaf or twig that may fall on them. Plants have developed a multi-compound approach toward resisting microbial infection. This is discussed in the article 1+1=5 but to be brief, phytocompounds within a single plant work together to combat any microbial dangers. Some species are known to have specific bacteria or fungi killing compounds, such as berberine, ellagitannins and flavanoids. Evidence has showed lower activity in some isolated compounds as compared to the whole profile activity, indicating that the whole plant is a more effective treatment than the single isolate. It is now being discovered that other, accessory, compounds are assisting the overall effectiveness of these actives, pivotal to creating a potent antimicrobial mixture.
To take this one step further, traditional Chinese medicine and Ayurveda (India) have been combining plants as effective treatments for infection and disease for thousands of years. Could there be synergistic relationships among phytochemicals, not only within a single species, but also across multiple species?
By utilizing the power of synergistic combinations of different botanicals, we can increase the effectiveness of an antimicrobial product while decreasing the likelihood of resistance from the target microbes. New studies are already applying combinational drug therapy on current antimicrobials, suggesting activity at lower doses and diminished antimicrobial resistance, perhaps we can replicate the same using botanical extracts. This could lead to a brand new way of developing safer and long lasting preservatives and antiseptics, that are friendlier to human health and global environment.
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