Phytochemical screening and biological assays of ethanolic leaf extract of Senna rugosa

Prospecting Plant Extracts and Bioactive Molecules with Antimicrobial Activity in Brazilian Biomes: A Review

Antimicrobial resistance is currently one of the greatest threats to global health, food security, and development. In this aspect, medicinal plants have been studied to support the development of viable alternatives to prevent and treat infectious diseases. This study aimed to perform a review of the literature comprising the antimicrobial activity of vegetable species from Brazilian biomes. We selected 67 original scientific publications about extracts, fractions, or isolated molecules from plants in the Brazilian biomes, published between 2016 and 2020 in Pubmed, ScienceDirect, and Scielo. Data demonstrated that 98 plant species, especially collected in the Cerrado, Atlantic Forest, and Caatinga biomes, were tested against 40 fungi and 78 bacterial strains. Bioactive fractions of Eucalyptus globulus methanolic stump wood extract were active against Candida albicans and C. tropicalis (MIC 2.50 µg/mL). The catechin purified from Banisteriopsis argyrophylla leaves had activity against C. glabrata (MIC 2.83 µg/mL) and ethanolic extract obtained from Caryocar coriaceum bark and fruit pulp exhibited MIC of 4.1 µg/mL on Microsporum canis. For bacteria, compounds isolated from the dichloromethane extract of Peritassa campestris, lectin extracted from a saline extract of Portulaca elatior and essential oils of Myrciaria pilosa exhibited significant effect against Bacillus megaterium (MIC 0.78 µg/mL), Pseudomonas aeruginosa (MIC 4.06 µg/mL) and Staphylococcus aureus strains (MIC 5.0 µg/mL), respectively. The findings support the antimicrobial and bioeconomic potential of plants from Brazilian biodiversity and their promising health applications.

Bioactive Natural Products for Chemical Control of Microorganisms: Scientific Prospecting (2001–2021) and Systematic Review

The inappropriate use of synthetic antibiotics has become a global public health problem. Therefore, the study of new alternatives for the treatment of infectious diseases is relevant and natural bioactive products are on the rise. This study conducted a scientific prospection of bioactive natural products with promising applications in the chemical control of microorganisms. A systematic review of the most recent articles was performed according to the following three steps: (i) eligibility assessment, (ii) screening, and (iii) inclusion of articles and information extraction. There has been an increase in the number of scientific publications on bioactive natural products for microbial control in the CAPES and SciELO databases (2001–2021). Seventeen relevant articles were included, most of which focused on extracts. Ascorbic acid, chlorogenic acid, chrysin, and quercetin were the most cited compounds. Natural products were shown to be effective in inhibiting more than 30 microorganisms. A discussion was presented on the research trends.

Senna podocarpa Emulgel: A Herbal Alternative for Chemical Burn Wound Treatment

Senna podocarpa (SP) leaves are used in folk medicines for treatment of burns and wounds as poultices on wound surface. However, to the best of our knowledge, the wound healing ability of this plant has not been scientifically evaluated. This work aimed to determine the wound healing potential of the crude extract of SP leaves, and to evaluate the benefit of its preparation as an emulgel. In this study, the formulations of 2.5% of SP emulgel (F1) and 7.5% of SP emulgel (F2) were prepared by mixing the emulsion phase with the gel phase in a ratio of 1:1, and then physical appearance, globule size, pH, viscosity, swelling, water activity, extrudability, occlusion, spreadability, stability, and wound healing ability were determined. Phytochemical screening showed the presence of alkaloids, saponins, tannins, cardiac glycosides, flavonoids, anthraquinones, and phenols within the hydro-ethanolic extract of SP leaves, and high flavonoid content is believed to be responsible for its healing attributes. Our formulations showed acceptable physical properties. Hematoxylin-eosin and Verhoeff–Van Gieson stain showed that F2 could induce the accumulation of fibroblasts, fibrocytes, inflammatory cells, gland cells, epidermal cells, adipocytes, and collagen in the process of wound healing in mice injured with hydrochloric acid. Encouragingly, the percent of wound contractions in mice treated with F1, F2, and SP leaf poultice were 64, 87, and 50, respectively, suggesting the superior healing properties exhibited by SP emulgel over SP leaf poultice, and this may due to the occlusive property of emulgels. In conclusion, F2 of crude extract of SP leaves has better pharmacological effects on burn and wound healing, and may represent a preferred choice to treat burn wounds in the future.