Assessing the antimicrobial activity of essential oils against skin microorganisms using flow cytometry

The skin microbiome, composed of bacteria like Staphylococcus spp. and Cutibacterium acnes and fungi such as Candida spp. and Malasseziaspp., plays a key role in skin health (Byrd et al., 2018). Dysbiosis, or microbial imbalance, is linked to conditions like acne and dermatitis (Egert etal., 2017). While conventional treatments, such as anti-inflammatory drugs and antimicrobials, can help, they may disrupt the microbiome andpromote resistance (Sfriso et al., 2020).Natural alternatives like essential oils (EOs) are gaining attention due to their terpene-rich composition, which targets multiple microbial structuresand reduces resistance risk (Zuzarte et al., 2011). Flow cytometry offers a precise method to assess antimicrobial effects by distinguishing livefrom dead cells through fluorescent staining (Shapiro, 2003).