Antimicrobial Testing of Schinus molle (L.) Leaf Extracts and Fractions Followed by GC-MS Investigation of Biological Active Fractions

Evidence for the efficacy of anti-inflammatory plants used in Brazilian traditional medicine with ethnopharmacological relevance

ETHNOPHARMACOLOGICAL RELEVANCE

When exacerbated, inflammatory processes can culminate in physical and emotional disorders and, if not stopped, can be lethal. The high prevalence of inflammation has become a public health problem, and the need for new drugs to treat this pathology is imminent. The use of medicinal plants has emerged as an alternative, and a survey of data that corroborates its application in inflammatory diseases is the starting point. Furthermore, Brazil harbors a megadiversity, and the traditional use of plants is relevant and needs to be preserved and carefully explored for the discovery of new medicines.

AIM OF THE STUDY

This review sought to survey the medicinal plants traditionally used in Brazil for the treatment of inflammatory processes and to perform, in an integrative way, a data survey of these species and analysis of their phytochemical, pharmacological, and molecular approaches.

MATERIALS AND METHODS

Brazilian plants that are traditionally used for inflammation (ophthalmia, throat inflammation, orchitis, urinary tract inflammation, ear inflammation, and inflammation in general) are listed in the DATAPLAMT database. This database contains information on approximately 3400 native plants used by Brazilians, which were registered in specific documents produced until 1950. These inflammatory disorders were searched in scientific databases (PubMed/Medline, Scopus, Web of Science, Lilacs, Scielo, Virtual Health Library), with standardization of DECS/MESH descriptors for inflammation in English, Spanish, French, and Portuguese, without chronological limitations. For the inclusion criteria, all articles had to be of the evaluated plant species, without association of synthesized substances, and full articles free available in any of the four languages searched. Duplicated articles and those that were not freely available were excluded.

RESULTS

A total of 126 species were identified, culminating in 6181 articles in the search. After evaluation of the inclusion criteria, 172 articles representing 40 different species and 38 families were included in the study. Comparison of reproducibility in intra-species results became difficult because of the large number of extraction solvents tested and the wide diversity of evaluation models used. Although the number of in vitro and in vivo evaluations was high, only one clinical study was found (Abrus precatorius). In the phytochemical analyses, more than 225 compounds, mostly phenolic compounds, were identified.

CONCLUSION

This review allowed the grouping of preclinical and clinical studies of several Brazilian species traditionally used for the treatment of many types of inflammation, corroborating new searches for their pharmacological properties as a way to aid public health. Furthermore, the large number of plants that have not yet been studied has encouraged new research to revive traditional knowledge.

Acute toxicity and genotoxicity of Schinus molle L. aqueous extract/ethanol-soluble fraction in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Schinus molle L. is a medicinal species belonging to the Anacardiaceae family. It is commonly referred to as "aroeira" and its leaves and roots are utilized for treating different pathological conditions. However, despite its widespread use in traditional medicine, there is a lack of in-depth toxicological studies.

AIM

To evaluate the acute toxicity and genotoxicity of S. molle aqueous extract/ethanol-soluble fraction in rats.

MATERIAL AND METHODS

First, a purified aqueous extract was obtained from the leaves of S. mole through infusion (referred to as EESM) and its compounds were identified using LC-DAD-MS data. Female rats were then subjected to acute oral toxicity tests using doses of 5, 50, 300, and 2000 mg/kg of ESSM. Studies on genetic material, including the micronucleus test and comet assay, were conducted on male and female Wistar rats using the same doses as in the acute toxicity test. For both assays, ESSM was administered orally.

RESULTS

The main metabolites annotated from ESSM were dimeric proanthocyanidins, phenylpropanoids acids, flavan-3-ols, simple organic acids (C6-C1), a flavonol di-O-glycosylated (rutin), and O-glycosylated megastigmane. The ESSM did not exhibit any acute toxic effects, such as changes in biochemical, hematologic, or histopathological analysis. Furthermore, no changes were observed in comet assay or micronucleus tests when rats were given doses of 5, 50, 300, or 2000 mg/kg of ESSM.

CONCLUSION

The results showed that the ESSM does not induce acute toxicity or exhibit genotoxicity up to a dose of 2000 mg/kg.

Mediterranean Plants with Antimicrobial Activity against Staphylococcus aureus, a Meta-Analysis for Green Veterinary Pharmacology Applications

Antimicrobial resistance (AMR) has emerged as a global health crisis, necessitating the search for innovative strategies to combat infectious diseases. The unique biodiversity of Italian flora offers a treasure trove of plant species and their associated phytochemicals, which hold immense potential as a solution to address AMR. By investigating the antimicrobial properties of Italian flora and their phytochemical constituents, this study aims to shed light on the potential of phyto-complexes as a valuable resource for developing novel or supportive antimicrobial agents useful for animal production.

In-silico and in-vitro assessments of some fabaceae, rhamnaceae, apocynaceae, and anacardiaceae species against Mycobacterium tuberculosis H37Rv and triple-negative breast cancer cells

Medicinal plants play a huge role in the treatment of various diseases in the Limpopo province (South Africa). Traditionally, concoctions used for treating tuberculosis and cancer are sometimes prepared from plant parts naturally occurring in the region, these include (but not limited to) Schotia brachypetala, Rauvolfia caffra, Schinus molle, Ziziphus mucronate, and Senna petersiana. In this study, the aim was to evaluate the potential antimycobacterial activity of the five medicinal plants against Mycobacterium smegmatis mc²155, Mycobacterium aurum A + , and Mycobacterium tuberculosis H37Rv, and cytotoxic activity against MDA-MB 231 triple-negative breast cancer cells. Phytochemical constituents present in R. caffra and S. molle were tentatively identified by LC-QTOF-MS/MS as these extracts showed antimycobacterial and cytotoxic activity. A rigorous Virtual Screening Workflow (VSW) of the tentatively identified phytocompounds was then employed to identify potential inhibitor/s of M. tuberculosis pantothenate kinase (PanK). Molecular dynamics simulations and post-MM-GBSA free energy calculations were used to determine the potential mode of action and selectivity of selected phytocompounds. The results showed that plant crude extracts generally exhibited poor antimycobacterial activity, except for R. caffra and S. molle which exhibited average efficacy against M. tuberculosis H37Rv with minimum inhibitory concentrations between 0.25-0.125 mg/mL. Only one compound with a favourable ADME profile, namely, norajmaline was returned from the VSW. Norajmaline exhibited a docking score of -7.47 kcal/mol, while, pre-MM-GBSA calculation revealed binding free energy to be -37.64 kcal/mol. All plant extracts exhibited a 50% inhibitory concentration (IC₅₀) of < 30 μg/mL against MDA-MB 231 cells. Flow cytometry analysis of treated MDA-MB 231 cells showed that the dichloromethane extracts from S. petersiana, Z. mucronate, and ethyl acetate extracts from R. caffra and S. molle induced higher levels of apoptosis than cisplatin. It was concluded that norajmaline could emerge as a potential antimycobacterial lead compound. Validation of the antimycobacterial activity of norajmaline will need to be performed in vitro and in vivo before chemical modifications to enhance potency and efficacy are done. S. petersiana, Z. mucronate, R.caffra and S. molle possess strong potential as key contributors in developing new and effective treatments for triple-negative breast cancer in light of the urgent requirement for innovative therapeutic solutions.

Plants with Antimicrobial Activity Growing in Italy: A Pathogen-Driven Systematic Review for Green Veterinary Pharmacology Applications

Drug resistance threatening humans may be linked with antimicrobial and anthelmintic resistance in other species, especially among farm animals and, more in general, in the entire environment. From this perspective, Green Veterinary Pharmacology was proven successful for the control of parasites in small ruminants and for the control of other pests such as varroa in bee farming. As in anthelmintic resistance, antimicrobial resistance (AMR) represents one of the major challenges against the successful treatment of infectious diseases, and antimicrobials use in agriculture contributes to the spread of more AMR bacterial phenotypes, genes, and proteins. With this systematic review, we list Italian plants with documented antimicrobial activity against possible pathogenic microbes. Methods: The literature search included all the manuscripts published since 1990 in PubMed, Web of Science, and Scopus using the keywords (i) “antimicrobial, plants, Italy”; (ii) “antibacterial, plant, Italy”; (iii) “essential oil, antibacterial, Italy”; (iv) “essential oil, antimicrobial, Italy”; (v) “methanol extract, antibacterial, Italy”; (vi) “methanol extract, antimicrobial, Italy”. Results: In total, 105 manuscripts that documented the inhibitory effect of plants growing in Italy against bacteria were included. One hundred thirty-five plants were recorded as effective against Gram+ bacteria, and 88 against Gram−. This will provide a ready-to-use comprehensive tool to be further tested against the indicated list of pathogens and will suggest new alternative strategies against bacterial pathogens to be employed in Green Veterinary Pharmacology applications.

GC-MS Profile, Antioxidant Activity, and In Silico Study of the Essential Oil from Schinus molle L. Leaves in the Presence of Mosquito Juvenile Hormone-Binding Protein (mJHBP) from Aedes aegypti

Schinus molle is a medicinal plant used as an anti-inflammatory and for rheumatic pain in the traditional medicine of Peru. On the other hand, Aedes aegypti is the main vector of several tropical diseases and the transmitter of yellow fever, chikungunya, malaria, dengue, and Zika virus. In this study, the aim was to investigate the antioxidant activity in vitro and the insecticidal activity in silico, in the presence of the mosquito juvenile hormone-binding protein (mJHBP) from Aedes aegypti, of the essential oil from S. molle leaves. The volatile phytochemicals were analyzed by gas chromatography-mass spectrometry (GC-MS), and the profile antioxidants were examined by DPPH, ABTS, and FRAP assays. The evaluation in silico was carried out on mJHBP (PDB: 5V13) with an insecticidal approach. The results revealed that EO presented as the main volatile components to alpha-phellandrene (32.68%), D-limonene (12.59%), and beta-phellandrene (12.24%). The antioxidant activity showed values for $\text{DPPH}=11.42\pm 0.08\mu \text{mol}\text{ET}/\text{g}$ , $\text{ABTS}=134.88\pm 4.37\mu \text{mol}\text{ET}/\text{g}$ , and $\text{FRAP}=65.16\pm 1.46\mu \text{mol}\text{ET}/\text{g}$ . Regarding the insecticidal approach in silico, alpha-muurolene and gamma-cadinene had the best biding energy on mJHBP ( $\Delta G=-9.7\text{kcal}/\text{mol}$ ), followed by beta-cadinene ( $\Delta G=-9.5\text{kcal}/\text{mol}$ ). Additionally, the volatile components did not reveal antioxidant activity, and its potential insecticidal effect would be acting on mJHBP from A. aegypti.

Composition of Phenolic Compounds in South African Schinus molle L. Berries

The Schinus molle tree is notoriously invasive in most parts of the world, and yet as a pseudospice, its berries potentially possess some significant health benefits which need to be explored. Therefore, polar metabolome of seed + husks (SH), husks (H), and de-hulled (DH) berries were profiled and quantified by untargeted metabolomics approach using UPLC-QTOF-MS. A total of 13 gallotannins, three phenolic acids, a phenolic acid glucoside, three phenolic acid esters, an organic acid, a gallotannin derivative, and nine flavonoids were detected and quantified. Phenolic acids ranged between 12.2–295.7; 4.9–77; and 89.7–1613.1 mg/kg in SH, DH seeds and H respectively. Flavonoids ranged between 1.8–267.5; 73.4–80.4; and 124–564.3 mg/kg in SH, DH seeds and H respectively. Gallotannins ranged between 1.1–146.6; 14.8–21.8; and 48.1–664.8 mg/kg in SH, DH seeds and H respectively. Feruloyltartaric A, quercetin 3-O-glucuronide, catechin digalloylshikimic acid B as well as digalloyl quinic acid were some of the dominant secondary metabolites revealed. These results indicate that S. molle berries are a rich source of secondary metabolites with elevated concentrations in the husks, while DH seeds possess lower concentrations to none. These findings open important insights into the potential of S. molle berries as a natural source of antioxidants for the food and pharmaceutical industries.