Two Diterpene Rhamnosides, Mimosasides B and C, from Mimosa hostilis

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.

Phytochemistry and poisoning in ruminants by Enterolobium contortisiliquum (Vell.) Morong (Fabaceae): A systematic review

Enterolobium contortisiliquum (Vell.) Morong (Fabaceae) is a plant widely distributed in several regions of Brazil, occurring in the phytogeographic domains of Atlantic Forest, Cerrado, and Caatinga. Cases of serious poisoning in cattle, goats, and sheep in the country caused by the ingestion of beans of this species have been reported by several studies. The present work aimed to carry out a systematic review of cases of poisoning by E. contortisiliquum in ruminants and list the main chemical compounds isolated from this plant. For this, searches were performed in the Google Academic, PubMed®, ScienceDirect®, and SciELO databases. A total of 26 articles published in the last 20 years (2001-2021) were included. Studies on cases of natural and experimental poisoning indicate that this species mainly causes photosensitization, abortions, digestive problems, and acute ruminal lactic acidosis in animals that ingest the pods of the plant. The main chemical compounds that occur in the species belong to the triterpene saponins, monoterpene, phenylpropene, and triterpene classes. It is likely that triterpene saponins isolated from E. contortisiliquum are associated with reported cases of photosensitization in cattle. New studies must be conducted to assess the mechanisms of action of chemical compounds isolated from this species in in vivo systems.

Phytochemistry and teratogenic potential of Mimosa tenuiflora (willd.) poir. (Fabaceae) in ruminants: A systematic review

Mimosa tenuiflora (Willd.) Poir. (Fabaceae) is a plant native to Brazil and occurs in the phytogeographic domains of Caatinga and Cerrado. Relevant studies have investigated the chemical components of this plant and others have already demonstrated its teratogenic potential. It has been proven that this plant causes congenital malformations in farm animals and, consequently, financial losses to farmers in the Brazilian semiarid region. The present work aimed to carry out a bibliographic survey on the teratogenic effects of M. tenuiflora in ruminants and to group the chemical compounds occurring in this species. For this, databases were consulted and twenty-four articles published in the last 30 years (1990-2020) were included. According to the scientific documents analyzed, M. tenuiflora has embryotoxic, fetotoxic and abortive potential in farm animals, especially sheep and goats. The main classes of chemical compounds present in this species are alkaloids, saponins, flavonoids, and terpenoids. It is likely that some of these substances, mainly the indole alkaloid N,N-dimethyltryptamine, are related to the teratogenic effects reported in ruminants in the Brazilian semiarid region.

Antinoceptive and Anti-inflammatory Activities of the Ethanolic Extract, Fractions and Flavones Isolated from Mimosa tenuiflora (Willd.) Poir (Leguminosae)

The bark of Mimosa tenuiflora (Willd.) Poiret (Leguminosae family), popularly known as “jurema preta” in Brazil, is used by the population of Contendas of Sincorá (Bahia State, Brazil) for the treatment of coughs and wound healing. Thus, the aim of this study was to evaluate the antinociceptive and anti-inflammatory activities of the bark ethanol extract (EEMT) and solvent soluble fractions (hexane—H, DCM—D, EtOAc—E and BuOH—B) of the extract in vivo. Additionally, we synthesized 5,7-dihidroxy-4’-methoxyflavanone (isosakuranetin) and isolated the compound sakuranetin, and both compounds were also tested. The anti-inflammatory and antinociceptive assays performed were: writhing test; nociception induced by intraplantar formalin injection; leukocyte recruitment to the peritoneal cavity; evaluation of vascular permeability (Evans blue test); and evaluation of mechanical hypernociception (von Frey test). Production of TNF-α, IL-10, myeloperoxidase and the expression of ICAM-1 were also evaluated. Statistical analysis was performed by one-way ANOVA followed by the Bonferroni post-test (n = 8), with P < 0.05. The EEMT showed antinociceptive activities in writhing test (100–200 mg/kg), in the second phase of the formalin test (50–200 mg/kg), and in mechanical hypernociception (100 mg/kg). EEMT showed an anti-inflammatory effect by reducing neutrophil migration to the peritoneal cavity and in the plantar tissue detected by the reduction of myeloperoxidase activity (100 mg/kg), reduction of IL-10 levels and expression of ICAM-1 in the peritoneal exudate and the mesentery (100 mg/kg), respectively. The four soluble EEMT fractions showed good results in tests for antinociceptive (H, D, E, B) and anti-inflammation (H, D, E). Only sakuranetin showed reduction of the writhing and neutrophil migration (200 mg/kg). Thus, the EEMT and soluble fractions of M. tenuiflora bark demonstrated great antinociceptive and anti-inflammatory activities, as also sakuranetin. More studies should be conducted to elucidate the mechanism of action of this compound. To the best of our knowledge, this is the first report on the antinociceptive activity of the M. tenuiflora fractions and the bioactive isolated compound sakuranetin in vivo.

Bioinspired total synthesis and structural revision of yuremamine, an alkaloid from the entheogenic plant Mimosa tenuiflora

Guided by a biosynthetic hypothesis, a serendipitous total synthesis of yuremamine has resulted in its structural revision from the putative pyrroloindole (1) to the flavonoidal indole (2), which was initially proposed as a biosynthetic intermediate.

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

Background:

Mimosa caesalpiniifolia Benth. (Leguminosae) is widely found in the Brazilian Northeast region and markedly contributes to production of pollen and honey, being considered an important honey plant in this region.

Objective:

To investigate the chemical composition of the ethanol extract of leaves from M. caesalpiniifolia by GC-MS after derivatization (silylation), as well as to evaluate the in vitro and in vivo toxicological effects and androgenic activity in rats.

Materials and Methods:

The ethanol extract of leaves from Mimosa caesalpiniifolia was submitted to derivatization by silylation and analyzed by gas chromatography-mass spectrometry (GC-MS) to identification of chemical constituents. In vitro toxicological evaluation was performed by MTT assay in murine macrophages and by Artemia salina lethality assay, and the in vivo acute oral toxicity and androgenic evaluation in rats.

Results:

Totally, 32 components were detected: Phytol-TMS (11.66%), lactic acid-2TMS (9.16%), α-tocopherol-TMS (7.34%) and β-sitosterol-TMS (6.80%) were the major constituents. At the concentrations analyzed, the ethanol extract showed low cytotoxicity against brine shrimp (Artemia salina) and murine macrophages. In addition, the extract did not exhibit any toxicological effect or androgenic activity in rats.

Conclusions:

The derivatization by silylation allowed a rapid identification of chemical compounds from the M. caesalpiniifolia leaves extract. Besides, this species presents a good safety profile as observed in toxicological studies, and possess a great potential in the production of herbal medicines or as for food consumption.

5-deoxyflavones with cytotoxic activity from Mimosa diplotricha

Bioassay-guided isolation of Mimosa diplotricha led to the isolation of four new 5-deoxyflavones, diplotrins A-C (1-3) and diplotasin (4), together with 12 known flavonoids, flavonolignans, and triterpenoids. On the basis of spectroscopic evidence, compounds 1-4 were characterized as 2',5'-dihydroxy-3,7,8,4'-tetramethoxyflavone (1), 3'-hydroxy-3,7,8,4'-tetramethoxyflavone (2), 2'-hydroxy-7,4',5'-trimethoxyflavone (3), and 4-hydroxy-3,10,11-trimethoxyisochromeno-[4,3-b]-chromen-7(5H)-one (4). The cytotoxic effects of these isolated compounds were evaluated against the A549, AGS, HT-29, and PC3 human cancer cell lines. Compounds 2 and 5″-methoxyhydnocarpin-D (5) showed the most potent antiproliferative activity.

Antioxidant phenylpropanoid-substituted epicatechins from Trichilia catigua

Two new phenylpropanoid-substituted epicatechins, namely, catiguanin A ( 1) and catiguanin B ( 2), were isolated from the bark of Trichilia catigua along with four known compounds, cinchonain Ia ( 3), cinchonain Ib ( 4), cinchonain Ic ( 5), and cinchonain Id ( 6). The structures of 1 and 2 were elucidated by analysis of spectroscopic data and by comparison of their NMR data with those of previously reported cinchonains. The isolated compounds exhibited potent antioxidant activity in the alpha,alpha-diphenyl-beta-picrylhydrazyl (DPPH) radical scavenging test, with IC 50 values in the 2.3-9.4 microM range.