Antimicrobial Profile of Premna pubescens. Blume and Centella asiatica Extracts Against Bacteria and Fungi Pathogens

Assessing the Efficiency of Antimicrobial Plant Extracts from Artemisia afra and Eucalyptus globulus as Coatings for Textiles

This study aimed to assess the antimicrobial activities of plant extracts from Artemisia afra and Eucalyptus globulus when used as coatings for textiles. A pulsed ultrasound-assisted extraction method (PUAE) was employed to obtain methanolic and hexanoic extracts from both plants. Eucalyptus globulus methanol extraction exhibited the highest yield at 22.76% (±0.61%), while Artemisia afra demonstrated lower yields. Phytochemical screening identified various secondary metabolites in the extracts, including phenols, quinones, and steroids. Antimicrobial tests against Staphylococcus aureus and Escherichia coli revealed varying degrees of susceptibility, with Eucalyptus globulus hexanoic extracts showing the highest activity against Staphylococcus aureus at an average percentage growth of 18.74% (±0.26%). Minimum inhibitory concentration (MIC) values were determined for the extracts, but complete inhibition did not occur at concentrations below 500 μg/mL. The extracts exhibited varying effects on Staphylococcus aureus and Escherichia coli growth, with some extracts promoting bacterial growth. Coating textiles with Eucalyptus globulus methanolic extracts demonstrated antibacterial activity against Staphylococcus aureus with the highest zone of inhibition observed in cotton-coated samples (258.4 mm2). Polyester-coated samples exhibited smaller inhibition zones, with the lowest observed in Eucalyptus globulus methanolic extract coating (65.97 mm2). Scanning electron microscope (SEM) analysis revealed visible surface morphology changes in coated fabrics, depicting fine, cluster, lumpy, flaky, and fragment-like morphologies. Laundering effects on coated fabrics were investigated, showing a significant decrease in antimicrobial activity after washing. Fourier-transform infrared spectroscopy (FTIR) identified functional groups in the extracts associated with antimicrobial properties. The complexity of the bioactive compounds suggests potential antimicrobial efficacy, resting on factors such as geographical location, climate, and extraction methods. Notwithstanding the limitations, this study contributes valuable insights into the use of plant extracts as antimicrobial coatings for textiles.

Extraction Methods, Quantitative and Qualitative Phytochemical Screening of Medicinal Plants for Antimicrobial Textiles: A Review

Medicinal plants are the product of natural drug discoveries and have gained traction due to their pharmacological activities. Pathogens are everywhere, and they thrive in ideal conditions depending on the nutrients, moisture, temperature, and pH that increase the growth of harmful pathogens on surfaces and textiles. Thus, antimicrobial agents and finishes may be the solution to the destruction of pathogens. This review article presents an analysis of various aspects of producing antimicrobial finishings, the microorganisms, their mechanism of attachment to natural and synthetic fibre, the effect of microbial growth, and the principle and mechanism of the microbial activity of the medicinal plants. Furthermore, the extraction methods, qualitative and quantitative phytochemical evaluations of antimicrobial efficacy, and developments of antimicrobial treated textiles using various agents are covered in this review.