Melanoma is the most aggressive form of skin cancer and arises from melanocyte gene mutation. This disease is multifactorial, but its main cause is the excessive exposure to ultraviolet radiation. Currently, available chemotherapy has shown little expressive results, which may justify the high use of natural products to treat this cancer. We performed a systematic review to compile the results of studies carried out in murine models and investigated the effect of plant extracts on melanoma treatment. Papers were selected in MEDLINE/Pubmed and Scopus according to the PRISM statement. Search filters were developed using three parameters: plant extract, melanoma, and animal model. The 35 identified studies were all submitted to the criteria described in the ARRIVE guidelines. The different extracts showed antiangiogenic, antimetastatic, antioxidant, and anti-inflammatory activity, and also proved to be effective in cell cycle modulation and apoptosis evasion. Bias analysis evidenced the absence of standardized experimental designs, as well as failures in statistical tests and in the presentation of results. The analysis of the studies suggests that the use of plant extracts is effective for the treatment of melanoma in murine models.

The dichloromethane extract of Plectranthus ornatus Codd., a tradicional medicinal plant, showed antibiotic activity with minimum inhibitory concentration (MIC) values of 0.4 mg.mL -1 and 100 percent of biofilm inhibition against Staphylococcus aureus strains isolated from animals with mastitis infections. Based on these antibacterial activities, in addition to ethnopharmacological reports from healing men and farmers in Brazil, an herbal soap was produced from this active extract and was tested both in vitro and in vivo. In vivo assays conducted on these herbal soaps led to results similar to those previously conducted with the active extract. These results indicated the great potential of this plant for use as an excipient by preparing herbal antibacterial soaps as an alternative veterinary medicine aimed at controlling bovine mastitis infections on small Brazilian farms.

The prophylactic and therapeutic overuse of antimicrobials on the farm has contributed to the emergence of hard-to-fight bacterial strains causing bovine mastitis. Aiming at alternative therapies, this study evaluated the antimicrobial activity of 20 essential oils against clinical Staphylococcus aureus strains. Of them, five with strong activities were selected and evaluated for their minimum inhibitory concentrations (MIC) in culture medium and milk, cytotoxicity against bovine mammary cells (MAC-T), anti-adhesive properties, and interactions among themselves and with cefoperazone. The oils remained active on milk, were not cytotoxic and, some concentrations stimulated MAC-T cells growth, suggesting healing potential. Subinhibitory concentrations of Coriandrim sativum, Origanum vulgare, Syzygium aromaticum and Thymus vulgaris reduced biofilm formation by at least 80%. Several oil and cefoperazone combinations displayed additive interaction, with O. vulgare and C. sativum showing the most promising results. We developed formulations for being used as prophylactic post-dipping solutions in the field, containing different concentrations (1 or 3%) of the active oils, alone or in combination, with 3% glycerin, 1% Tween 80 and water. The formulations showed strong antimicrobial activity in milk and enhanced anti-adhesive properties, specially when two oils were combined in the formula, indicating promising biotechnological and therapeutical applications.