Chemical constituents and toxicological studies of leaves from Mimosa caesalpiniifolia Benth., a Brazilian honey plant

Chemotherapeutic and Safety Profile of a Fraction from Mimosa caesalpiniifolia Stem Bark

Mimosa caesalpiniifolia (Fabaceae) is used by Brazilian people to treat hypertension, bronchitis, and skin infections. Herein, we evaluated the antiproliferative action of the dichloromethane fraction from M. caesalpiniifolia (DFMC) stem bark on murine tumor cells and the in vivo toxicogenetic profile. Initially, the cytotoxic activity of DFMC on primary cultures of Sarcoma 180 (S180) cells by Alamar Blue, trypan, and cytokinesis block micronucleus (CBMN) assays was assessed after 72 h of exposure, followed by the treatment of S180-bearing Swiss mice for 7 days, physiological investigations, and DNA/chromosomal damage. DFMC and betulinic acid revealed similar in vitro antiproliferative action on S180 cells and induced a reduction in viable cells, induced a reduction in viable cells and caused the emergence of bridges, buds, and morphological features of apoptosis and necrosis. S180-transplanted mice treated with DFMC (50 and 100 mg/kg/day), a betulinic acid-rich dichloromethane, showed for the first time in vivo tumor growth reduction (64.8 and 80.0%) and poorer peri- and intratumor quantities of vessels. Such antiproliferative action was associated with detectible side effects (loss of weight, reduction of spleen, lymphocytopenia, and neutrophilia and increasing of GOT and micronucleus in bone marrow), but preclinical general anticancer properties of the DFMC were not threatened by toxicological effects, and these biomedical discoveries validate the ethnopharmacological reputation of Mimosa species as emerging phytotherapy sources of lead molecules.

A Comprehensive Review of the Ethnotraditional Uses and Biological and Pharmacological Potential of the Genus Mimosa

The Mimosa genus belongs to the Fabaceae family of legumes and consists of about 400 species distributed all over the world. The growth forms of plants belonging to the Mimosa genus range from herbs to trees. Several species of this genus play important roles in folk medicine. In this review, we aimed to present the current knowledge of the ethnogeographical distribution, ethnotraditional uses, nutritional values, pharmaceutical potential, and toxicity of the genus Mimosa to facilitate the exploitation of its therapeutic potential for the treatment of human ailments. The present paper consists of a systematic overview of the scientific literature relating to the genus Mimosa published between 1931 and 2020, which was achieved by consulting various databases (Science Direct, Francis and Taylor, Scopus, Google Scholar, PubMed, SciELO, Web of Science, SciFinder, Wiley, Springer, Google, The Plant Database). More than 160 research articles were included in this review regarding the Mimosa genus. Mimosa species are nutritionally very important and several species are used as feed for different varieties of chickens. Studies regarding their biological potential have shown that species of the Mimosa genus have promising pharmacological properties, including antimicrobial, antioxidant, anticancer, antidiabetic, wound-healing, hypolipidemic, anti-inflammatory, hepatoprotective, antinociceptive, antiepileptic, neuropharmacological, toxicological, antiallergic, antihyperurisemic, larvicidal, antiparasitic, molluscicidal, antimutagenic, genotoxic, teratogenic, antispasmolytic, antiviral, and antivenom activities. The findings regarding the genus Mimosa suggest that this genus could be the future of the medicinal industry for the treatment of various diseases, although in the future more research should be carried out to explore its ethnopharmacological, toxicological, and nutritional attributes.

Toxicological, chemopreventive, and cytotoxic potentialities of rare vegetal species and supporting findings for the Brazilian Unified Health System (SUS)

Caatinga flora which are found in a poor Brazilian region contain a substantial number of endemic taxa with biomedical and social importance for regional communities. This study examined the antioxidant and cytotoxic potential of 35 samples (extracts/fractions) from 12 Caatinga species and determined the antiproliferative and genotoxic action of dichloromethane fraction from Mimosa caesalpiniifolia stem bark (DC-Mca) on human and vegetal cells. Samples were assessed for chemopreventive ability, toxic effects on Artemia salina shrimp as well as cytotoxicity on tumor cell lines and erythrocytes. DC-Mca was also tested with respect to antiproliferative and genotoxic effects upon normal leukocytes and meristematic cells from A. cepa roots. Some extracts reduced free radical levels >95% and 7 samples exhibited a lethal concentration (LC) ₅₀ < 100 µg/ml upon Artemia salina larvae. Eight samples displayed in vitro antitumor effects and three produced hemolysis. Data also demonstrated the pharmacological significance of bioactive extracts from Brazilian semi-arid region. There was no significant relationship between antioxidant, toxic, and antiproliferative activities, and that these properties were dependent upon the extractant. DC-Mca contained betulinic acid as main compound (approximately 70%), which showed higher (1) cytotoxic activity on cancer cell lines and dividing leukocytes, (2) reduced mitotic index of Allium cepa roots, and (3) induced cell cycle arrest and chromosomal bridges, thereby providing native promising sources for phytotherapy development.

ABBREVIATIONS

ABTS: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid); AcOH: ethyl acetate; ANOVA: analysis of variance; SUS: Brazilian Unified Health System; DC-Mca: dichloromethane fraction from Mimosa caesalpiniifolia stem bark; DMSO: dimethylsulfoxide; DPPH: 1,1-diphenyl-2-picrylhydrazyl; EC₅₀: effective concentration 50%; EtOAc: ethyl acetate; FDA: Food and Drug Administration; GC-Qms: gas chromatograph quadrupole mass spectrometer; GI: genotoxic index; HCT-116: colon carcinoma line; HL-60: promyelocytic leukemia line; HPLC: high-performance liquid chromatography; HRAPCIMS: high resolution atmospheric pressure chemical ionization mass spectrum; IC₅₀: inhibitory concentration 50%; LC₅₀: lethal concentration 50%; MeOH = methyl alcohol; MI: mitotic index; MTT: 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide; MutI: mutagenic index; OVCAR-8 = ovarian carcinoma line; PBMC: peripheral blood mononuclear cells; RPMI-1640: Roswell Park Memorial Institute medium; SF-295: glioblastoma line; TEAC: trolox equivalent antioxidant capacity; TLC: thin-layer chromatography; Trolox: 6-hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid.

Bioassay-Guided Isolation of Fungistatic Compounds from Mimosa caesalpiniifolia Leaves

A bioassay-guided phytochemical study of a Mimosa caesalpiniifolia leaf extract with antifungal activity permitted the identification of 28 compounds, including the new 6-(β-boivinopyranosyl)apigenin (1), 8-(β-oliopyranosyl)apigenin (2), (E)-6-(2-carboxyethenyl)apigenin (3), (E)-8-(2-carboxyethenyl)apigenin (4), and 7,5″-anhydro-6-(α-2,6-dideoxy-5-hydroxyarabinohexopyranosyl)apigenin (5). The structures of the new compounds were determined by comprehensive spectroscopic analysis, including 1D and 2D NMR techniques, and by mass spectrometry. Compound 3 showed promising activity and selectivity against Candida krusei (IC₅₀ 44 nM), which exhibits resistance to azoles. The association of the major components 3-β-d-glucopyranosyloxysitosterol (8) and ethyl gallate (10) was synergistic against C. krusei, especially the IC values of compound 10, which were reduced by more than 100-fold.

Assessing chemical constituents of Mimosa caesalpiniifolia stem bark: possible bioactive components accountable for the cytotoxic effect of M. caesalpiniifolia on human tumour cell lines

Mimosa caesalpiniifolia is a native plant of the Brazilian northeast, and few studies have investigated its chemical composition and biological significance. This work describes the identification of the first chemical constituents in the ethanolic extract and fractions of M. caesalpiniifolia stem bark based on NMR, GC-qMS and HRMS analyses, as well as an assessment of their cytotoxic activity. GC-qMS analysis showed fatty acid derivatives, triterpenes and steroid substances and confirmed the identity of the chemical compounds isolated from the hexane fraction. Metabolite biodiversity in M. caesalpiniifolia stem bark revealed the differentiated accumulation of pentacyclic triterpenic acids, with a high content of betulinic acid and minor amounts of 3-oxo and 3β-acetoxy derivatives. Bioactive analysis based on total phenolic and flavonoid content showed a high amount of these compounds in the ethanolic extract, and ESI-(-)-LTQ-Orbitrap-MS identified caffeoyl hexose at high intensity, as well as the presence of phenolic acids and flavonoids. Furthermore, the evaluation of the ethanolic extract and fractions, including betulinic acid, against colon (HCT-116), ovarian (OVCAR-8) and glioblastoma (SF-295) tumour cell lines showed that the crude extract, hexane and dichloromethane fractions possessed moderate to high inhibitory activity, which may be related to the abundance of betulinic acid. The phytochemical and biological study of M. caesalpiniifolia stem bark thus revealed a new alternative source of antitumour compounds, possibly made effective by the presence of betulinic acid and by chemical co-synergism with other compounds.