Leishmanicidal and antimicrobial activity of primin and primin-containing extracts from Miconia willdenowii

Health functions and related molecular mechanisms of Miconia genus: A systematic review

The Miconia genus is traditionally used in folk medicine in Brazil and other tropical American countries and is represented by 282 species in this region. It is a multifaceted genus of medicinal plants widely used to treat rheumatoid arthritis (RA), pain, inflammatory diseases, and many more therapeutic applications. In the present study, we systematically identify and discuss the literature on in vivo and in vitro studies focusing on the therapeutic potentials and related molecular mechanisms of the Miconia genus. The review also assessed phytochemicals and their pharmacological properties and considered safety concerns related to the genus. Literature searches to identify studies on the Miconia genus were carried out through four main electronic databases, namely PubMed, Embase, Scopus, and Web of Science limited to Medical Subjects Headings (MeSH) and Descriptores en Ciencias de la Salud (DCS) (Health Sciences Descriptors) to identify studies published up to December 2022. The relevant information about the genus was gathered using the keywords 'Miconia', 'biological activities', 'therapeutic mechanisms', 'animal model, 'cell-line model', 'antinociceptive', 'hyperalgesia', 'anti-inflammatory', and 'inflammation'. The therapeutic potentials and mechanisms of action of 14 species from genus Miconia were examined in 18 in vitro studies and included their anti-inflammatory, anticancer, analgesic, antibacterial, cytotoxic, mutagenic, antioxidant, anti-leishmanial, antinociceptive, schistosomicidal, and anti-osteoarthritis potentials, and in eight in vivo studies, assessing their analgesic, antioxidant, antinociceptive, and anti-osteoarthritis activities. Some of the main related molecular mechanisms identified are the modulation of cytokines such as IL-1β, IL-6, and TNF-α, as well as the inhibition of inflammatory mediators and prostaglandin synthesis. The limited number of studies showed that commonly available species from the genus Miconia are safe for consumption. Miconia albicans Sw.Triana and Miconia rubiginosa (Bonpl.) DC was the most frequently used species and showed significant efficacy and potential for developing safe drugs to treat pain and inflammation.

The Genus Miconia Ruiz & Pav. (Melastomataceae): Ethnomedicinal Uses, Pharmacology, and Phytochemistry

Species of the genus Miconia are used in traditional medicine for the treatment of diseases, such as pain, throat infections, fever, and cold, and they used as depuratives, diuretics, and sedatives. This work reviewed studies carried out with Miconia species, highlighting its ethnomedicinal uses and pharmacological and phytochemical potential. This information was collected in the main platforms of scientific research (PubMed, Scopus, and Web of Science). Our findings show that some of the traditional uses of Miconia are corroborated by biological and/or pharmacological assays, which demonstrated, among other properties, anti-inflammatory, analgesic, antimutagenic, antiparasitic, antioxidant, cytotoxic, and antimicrobial activities. A total of 148 chemical compounds were identified in Miconia species, with phenolic compounds being the main constituents found in the species of this genus. Such phytochemical investigations have demonstrated the potential of species belonging to this genus as a source of bioactive substances, thus reinforcing their medicinal and pharmacological importance.

Flavanone Glycosides, Triterpenes, Volatile Compounds and Antimicrobial Activity of Miconia minutiflora (Bonpl.) DC. (Melastomataceae)

Chemical composition of the essential oils and extracts and the antimicrobial activity of Miconia minutiflora were investigated. The flavanone glycosides, pinocembroside and pinocembrin-7-O-[4″,6″-HHDP]-β-D-glucose, were identified, along with other compounds that belong mainly to the triterpene class, besides the phenolics, gallic acid and methyl gallate. Sesquiterpenes and monoterpenes were the major compounds identified from the essential oils. Screening for antimicrobial activity from the methanolic extract of the leaves showed that the MIC and MMC values against the tested microorganisms ranged from 0.625 to 5 mg·mL−1 and that the extract was active against microorganisms, Staphyloccocus aureus, Escherichia coli, and Bacillus cereus.