Screening of the in vitro antileishmanial activities of compounds and secondary metabolites isolated from Maytenus guianensis Klotzsch ex Reissek (Celastraceae) chichuá Amazon

Citrus sinensis Peel Oil Extraction and Evaluation as an Antibacterial and Antifungal Agent

Throughout the tropical and subtropical climates, the genus Citrus can be found. The current study was conducted to extract the Citrus sinensis peel oil and evaluate its antibacterial, antifungal and antiparasitic potential. Petroleum ether was used to extract the C. sinensis peel oil through a Soxhlet apparatus. The antimicrobial and antifungal potential was determined via agar well diffusion method and minimum inhibitory concentrations (MIC) were calculated (test bacterial strains: Staphylococcus aureus, Escherichia coli and Streptococcus agalactiae; test fungal strains: Aspergillus flavus, Aspergillus niger, Altrnaria alternata). Antiparasitic activity against Leishmaniatropica was determined following standard protocol using amphotericin-B as positive and Dimethyl Sulfoxide (DMSO) as a negative control and the percentage inhibition was calculated. The oil extracted was brownish yellow with a tangy smell, water-insoluble, density (0.778 g/cm³) and specific gravity (0.843 g/cm). In antibacterial activity, the diameter of the zone of inhibition was maximum against E. coli (14 mm) and minimum for S. agalactiae (10 mm). While in antifungal activity diameter of the zone of inhibition was maximum against A. flavus (12.5 mm) and minimum for A. alternata (8.6 mm). S. agalactiae exhibited the minimum MIC value (6 mg/mL) and in fungal strains A. alternata exhibited the minimum value (2 mm). Citrus sinensis peel oil displayed antileishmanial efficiency of 60% at 50 μg/mL concentration after 48 h of incubation. C. sinensis peel oil demonstrated antimicrobial capabilities, implying that it could be used as a natural preservative in food or as an effective treatment against a variety of pathogenic organisms. Industries should extract oil from the waste of citrus fruits which will be beneficial from an economic point of view.

Pentacyclic Triterpenoids Isolated from Celastraceae: A Focus in the 13C-NMR Data

The Celastraceae family comprises about 96 genera and more than 1.350 species, occurring mainly in tropical and subtropical regions of the world. The species of this family stand out as important plant sources of triterpenes, both in terms of abundance and structural diversity. Triterpenoids found in Celastraceae species display mainly lupane, ursane, oleanane, and friedelane skeletons, exhibiting a wide range of biological activities such as antiviral, antimicrobial, analgesic, anti-inflammatory, and cytotoxic against various tumor cell lines. This review aimed to document all triterpenes isolated from different botanical parts of species of the Celastraceae family covering 2001 to 2021. Furthermore, a compilation of their ¹³C-NMR data was carried out to help characterize compounds in future investigations. A total of 504 pentacyclic triterpenes were compiled and distinguished as 29 aromatic, 50 dimers, 103 friedelanes, 89 lupanes, 102 oleananes, 22 quinonemethides, 88 ursanes and 21 classified as others.

In Vitro Susceptibility of Kinetoplastids to Celastroloids from Maytenus chiapensis

Leishmaniasis and Chagas are among the most significant neglected tropical diseases. Due to several drawbacks with the current chemotherapy, developing new antikinetoplastid drugs has become an urgent issue. In the present work, a bioassay-guided investigation of the root bark of Maytenus chiapensis on Leishmania amazonensis and Trypanosoma cruzi led to the identification of two D:A-friedo-nor-oleanane triterpenoids (celastroloids), 20β-hydroxy-tingenone (celastroloid 5) and 3-O-methyl-6-oxo-tingenol (celastroloid 8), as promising antikinetoplastid leads. They displayed higher potency on L. amazonensis promastigotes (50% inhibitory concentrations [IC50s], 0.44 and 1.12 μM, respectively), intracellular amastigotes (IC50s, 0.83 and 1.91 μM, respectively), and T. cruzi epimastigote stage (IC50s, 2.61 and 3.41 μM, respectively) than reference drugs miltefosine and benznidazole. This potency was coupled with an excellent selectivity index on murine macrophages. Mechanism of action studies, including mitochondrial membrane potential (Δψm) and ATP-level analysis, revealed that celastroloids could induce apoptotic cell death in L. amazonensis triggered by the mitochondria. In addition, the structure-activity relationship is discussed. These findings strongly underline the potential of celastroloids as lead compounds to develop novel antikinetoplastid drugs.

Larvicidal activity of Maytenus guianensis (Celastraceae) against Aedes aegypti (Diptera: Culicidae)

INTRODUCTION:

Bioprospection of plant products is used to discover new insecticides.

METHODS:

The larvicidal activity of ethanolic extract and triterpene (tingenone B) from the bark of Maytenus guianensis and their effect on pupation and emergence were evaluated against Aedes aegypti.

RESULTS:

Crude extract LC₅₀ was 11.3 ppm and caused ejection of the larvae intestine; tingenone B LC₅₀ was 14.8 ppm. Pupation was reduced by 20% and 10%, respectively; however, the emergence was not affected.

CONCLUSIONS:

The crude bark extract exhibited a higher larvicidal effect against the vector.

Recent researches in effective antileishmanial herbal compounds: narrative review

Leishmaniasis are neglected diseases and a public health problem; they are caused by protozoan species belonging to the genus Leishmania and mostly influences the poor populations in many developing countries. The lack of effective medications, and an approved vaccine, high toxicity and life-threatening side effects and many cases of drug resistance reported in different countries have resulted in the necessity to discover new, efficient, inexpensive, and safe antileishmanial compounds with less or no toxicity. This increase in consumer demand of natural herbal-derived plant extracts as alternative medicines continues despite the low scientific information to establish their efficacy and safety profiles. Various studies have been conducted so far concerning the application of herbal medicines for the treatment of leishmaniasis, but research on relatively effective and low toxic substances is still needed. In this review, we have summarized recent developments and reported studies concerning about herbal and naturally derived therapeutics in the treatment of leishmaniasis, conducted by several researchers worldwide. Some of these medical herbs with promising results have undergone prospective clinical researches, but many others have either not yet been explored. Recent articles described these medical herbs and their active and important molecules, including quinones, phenolic derivatives, lignans, tannins, terpenes, and oxylipins. We searched ISI Web of Science, PubMed, SID, Scholar, Scopus, and Science Direct, and articles published up to 2019 were included. The keywords of leishmaniasis and some words associated with herbal medicines and natural products were used in our search. This review can serve as a quick reference database for researchers.

Antibacterial activity of fractions and isolates of Maytenus guianensis Klotzsch ex Reissek (Celastraceae) Chichuá Amazon

INTRODUCTION

This aim of this study was to evaluate the antibacterial activity of fractions and isolates of Maytenus guianensis, a plant species used in Amazonian folk medicine.

METHODS

A disk diffusion technique was used to investigate the antibacterial potential.

RESULTS

The hexanic fractions and tingenone B isolate showed inhibitory effects against Staphylococcus aureus and Streptococcus pneumoniae.

CONCLUSIONS

These results indicate the antibacterial potential of this species and will enable future studies to identify novel therapeutic alternatives from this species.

Effect of the solid state fermentation of cocoa shell on the secondary metabolites, antioxidant activity, and fatty acids

During cocoa (Theobroma cacao L.) processing, the accumulated cocoa shell can be used for bioconversion to obtain valuable compounds. Here, we evaluate the effect of solid-state fermentation of cacao flour with Penicillium roqueforti on secondary metabolite composition, phenol, carotenoid, anthocyanin, flavonol, and fatty acids contents, and antioxidant activity. We found that the total concentrations of anthocyanins and flavonols did not change significantly after fermentation and the phenolic compound and total carotenoid concentrations were higher. The fermentation process produced an increase in saponin concentration and antioxidant activity, as well as significant changes in the levels of oleic, linoleic, gamma-linolenic, and saturated fatty acids. Based on our findings, we propose that the reuse of food residues through solid state fermentation is viable and useful.