Plant-Derived Products as Antibacterial and Antifungal Agents in Human Health Care

Abstract

A number of papers reporting antimicrobial properties of extracts, essential oils, resins and various classes of compounds isolated from higher plants has been published in recent years; however, a comprehensive analysis of plant-derived antimicrobial agents currently applied in practice for improvement of human health is still lacking. This review summarizes data on clinical efficacy, antimicrobial effects and the chemistry of commercially available antibacterial and antifungal agents of plant origin currently used in the prevention and treatment of gastrointestinal, oral, respiratory, skin, and urinary infections. As a result of an analysis of the literature, more than 40 plant-derived over-the-counter pharmaceuticals, dietary supplements, cosmetics, herbal medicines, and functional foods containing complex mixtures (e.g. Glycyrrhiza glabra extract, Melaleuca alternifolia essential oil, and Pistacia lentiscus resin), pure compounds (e.g. benzoic acid, berberine, eucalyptol, salicylic acid and thymol) as well as their derivatives and complexes (e.g. bismuth subsalicylate and zinc pyrithione) have been identified. The effectiveness of many of these products is illustrated by results of clinical trials and supported by data on their in vitro antimicrobial activity. A broad spectrum of various commercial products currently available on the market and their well-documented clinical efficacy suggests that plants are prospective sources for the identification of new types of antimicrobial agents in future. Innovative approaches and methodologies for effective proof-of-concept research and the development of new types of plant-derived products effective against recently emerging problems related to human microbial diseases (e.g. antimicrobial resistance) are also proposed in this review.

Volatile Antimicrobial Agents and In Vitro Methods for Evaluating Their Activity in the Vapour Phase: A Review

“…Nevertheless, despite this approach, measuring especially the qualitative parameters, the quantitative assessment of the vapour phase remains problematic. The final interpretation of results obtained by in vitro antimicrobial assay methods should be critically evaluated, as has been previously reported by Kokoska et al [29]. Only antibacterials with MIC values below 100 µg/mL for mixtures such as EOs and ≤ 16 µg/mL for pure volatile compounds should be considered as providing interesting activity, whereas samples with respective MICs higher than 1000 µg/mL and 100 µg/mL should strictly be described as non-active.…”

“…Currently, various over-the-counter pharmaceuticals, cosmetics, and herbal medicines containing EOs derived from plants (e.g., Melaleuca alternifolia) and their volatile compounds (e.g., eucalyptol and thymol) with proven clinical efficacy are used for the prevention and treatment of oral, respiratory, and skin infections in humans [29]. A few food preservatives consisting of EOs from Citrus spp., Rosmarinus officinalis, and Salvia officinalis are also already commercially available for application in various food products [30].…”

Mechanism and challenges associated with adaptation and evolution of drug-resistant bacteria: an overview

“…Phyllanthin compound extracted from Phyllanthus amarus plant is able to modulate fluoroquinolone-resistance by inhibiting NorA efflux pump in Staphylococcu aureus SA1199-B strain and could be a potential agent to treat infection (Ribeiro et al, 2019). A number of studies also reporting the antimicrobial activities of the number of extracts, essential oils, resins and various compounds derived from herbal plants in recent years (Kokoska et al, 2019). Recently characterization of vaginal microbiota Lactobacillus strain is studied for lactic acid and bacteriocin production (Fuochi et al, 2017).…”

Multidrug Resistance in Zoonotic Pathogens: Are Medicinal Plants a Therapeuthic Alternative?

“…be dependent on geochemical conditions in the soil [7,8]. Antibiotic resistance seems to be positively strongly correlated with the heavy metal pollution of the environment [7,[9][10][11][12].…”