Exploring the Fluconazole-Resistance Modifying Activity and Potential Mechanism of Action of Fixed Oil from Caryocar coriaceum Wittm. (Caryocaraceae) against Candida Species.

The fixed oil from the inner mesocarp of Caryocar coriaceum Wittm. is used in the Chapada do Araripe region of Brazil for the treatment of genitourinary candidiasis. This study aimed to evaluate the chemical composition, antifungal activity, reduction of fungal virulence, and the preliminary toxicity of the fixed oil from the inner mesocarp of C. coriaceum tested against three Candida yeasts. The oil was characterized by gas chromatography (GC-MS and GC-FID). Antifungal activity was assessed using the serial microdilution method. Additionally, the potential of the oil as an enhancer of fluconazole action was tested at sub-inhibitory concentrations (MIC/8). The mechanism of action of C. coriaceum fixed oil was determined by evaluating the inhibition of morphological transition in Candida spp. The chemical composition of the fixed oil of C. coriaceum comprised both unsaturated and saturated fatty acids. Oleic (61 %) and palmitic (33 %) acids were the major constituents. Regarding its anti-Candida activity, the oil inhibited the growth of C. albicans (IC50 : 371 µg/mL) and C. tropicalis (IC50 : 830 µg/mL). Furthermore, the oil reversed the antifungal resistance of C. albicans and C. tropicalis, restoring the susceptibility to fluconazole and reducing their IC50 from 12.33 µg/mL and 362 µg/mL to 0.22 µg/mL and 13.93 µg/mL, respectively. The fixed oil of C. coriaceum completely inhibited the morphological transition of C. albicans and C. tropicalis at a concentration of 512 µg/mL, but exhibited limited low antifungal potential against C. krusei. The observed antifungal activity may be attributed to the overproduction of reactive oxygen species. Additionally, the oil showed no toxic effect on the Drosophila melanogaster in vivo model. The fixed oil from the inner mesocarp of C. coriaceum emerge as a strong candidate for the development of new pharmaceutical formulations to treat infections caused by Candida spp.

Caryocar coriaceum fruits as a potential alternative to combat fungal and bacterial infections: In vitro evaluation of methanolic extracts.

Caryocar coriaceum, commonly known as 'pequi', is a medicinal species used traditionally for the herbal treatment of infectious and parasitic diseases in the Brazilian Northeast region. In this study, we investigated whether the fruits of C. coriaceum have bioactive chemical constituents against etiological agents of infectious diseases. The methanolic extract of the internal mesocarp of the fruits of C. coriaceum (MECC) was chemically analyzed and evaluated for its antimicrobial and drug-enhancing activity against multidrug-resistant pathogenic bacteria (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus), and Candida spp. strains. The extract had flavones, flavonols, xanthones, catechins, and flavanones as major classes. A total of 11.26 mg GAE/g of phenolics, and 5.98 mg QE/g of flavonoids were found. No intrinsic antibacterial activity was observed; however, the extract was able to intensify the action of gentamicin and erythromycin against multi-resistant strains. The anti-Candida effect observed in this study was mainly due to the formation of reactive oxygen species. The extract was capable of causing damage to the plasmatic membrane of Candida tropicalis through pores formation. Our findings partially support the ethnopharmacological uses of the fruit pulp of C. coriaceum against infectious and parasitic diseases.

Orally hypoglycemic activity of an insulin mimetic glycoprotein isolated from Cnidoscolus quercifolius Pohl. (Euphorbiaceae) seeds, Cq-IMP.

The genus Cnidoscolus (Euphorbiaceae) is widely distributed in tropical areas. In the Northeast of Brazil, the species C. quercifolius is endemic and has been used in traditional medicine. In this study, a novel protein was isolated from C. quercifolius seeds and characterized by its molecular weight, primary structure, isoelectric point (pI), and carbohydrate content. The hypoglycemic activity of this protein was investigated by in vitro assay with the RIN-5F glucose-responsive cell line and in vivo test using alloxan-induced diabetic mice models. In addition, safe use of the protein was also investigated by cytotoxicity, hemagglutinating, and immunogenicity assays. The protein which was named Cq-IMP (Cnidoscolus quercifolius - Insulin Mimetic Protein) showed a single 11.18 KDa glycopolypeptide chain (16.4% of carbohydrates, m/m), pI of 8.0 and N-terminal sequence (TKDPELKQcKKQQKKqQQYDDDDKK) with similarity around 46-62% to sucrose binding protein-like and vicilin-like protein that was confirmed by mass spectrometry tryptic peptides analysis. Besides that, Cq-IMP presented anti-insulin antibody cross-reactivity as hypoglycemic activity in both in vitro and in vivo models. Additionally, it did not present any toxicity by methods tested. In conclusion, Cq-IMP is an insulin-mimetic protein, with a potent hypoglycemic activity and no toxicity showing great potential for therapeutic applications and drug development.

Mo-CBP4, a purified chitin-binding protein from Moringa oleifera seeds, is a potent antidermatophytic protein: In vitro mechanisms of action, in vivo effect against infection, and clinical application as a hydrogel for skin infection.

Dermatophytes belonging to Trichophyton ssp. are important anthropophilic and zoophilic pathogens, which developed resistance to griseofulvin, the common antifungal drug used to treat dermatophytosis. In this context, Moringa oleifera seed proteins have been described as antifungal agents with potential applications. Thus, this work aimed to evaluate the antidermatophytic in vitro, focusing on mechanisms, and in vivo potential of Mo-CBP4, purified from M. oleifera seeds. Mo-CBP4was purified after protein extraction with 50 mM Tris-HCl buffer, pH 8.0, and chromatography on chitin and CM Sepharose™ columns and antidermatophytic potential of Mo-CBP4 evaluated in vitro and in vivo. In vitro, Mo-CBP4 reduced in 50% the germination of microconidia of Trichophyton mentagrophytes at 45 µM; but did not show inhibition of mycelial growth. Mo-CBP4 (45 µM) presents the inhibitory activity even when incubated with N-acetyl-d-glucosamine (NAG). Analysis of the mechanisms of Mo-CBP4 revealed an increase in membrane permeability, ROS overproduction and damage to cell wall leading to microconidia death. Furthermore, using in vivo models, Mo-CBP4 (5, 10 and 20 mg g-1) reduced the severity and time of dermatophytosis. Altogether, these findings indicate that Mo-CBP4 has great potential for the development of novel antifungal drugs for the clinical treatment of dermatophytosis.

Role of membrane sterol and redox system in the anti-candida activity reported for Mo-CBP2, a protein from Moringa oleifera seeds.

Plant proteins are emerging as an alternative to conventional treatments against candidiasis. The aim of this study was to better understand the mechanism of action of Mo-CBP2 against Candida spp, evaluating redox system activity, lipid peroxidation, DNA degradation, cytochrome c release, medium acidification, and membrane interaction. Anti-candida activity of Mo-CBP2 decreased in the presence of ergosterol, which was not observed with antioxidant agents. C. albicans treated with Mo-CBP2 also had catalase and peroxidase activities inhibited, while superoxide dismutase was increased. Mo-CBP2 increased the lipid peroxidation, but it did not alter the ergosterol profile in live cells. External medium acidification was strongly inhibited, and cytochrome c release and DNA degradation were detected. Mo-CBP2 interacts with cell membrane constituents, changes redox system enzymes in C. albicans and causes lipid peroxidation by ROS overproduction. DNA degradation and cytochrome c release suggest apoptotic or DNAse activity. Lipid peroxidation and H+-ATPases inhibition may induce the process of apoptosis. Finally, Mo-CBP2 did not have a cytotoxic effect in mammalian Vero cells. This study highlights the biotechnological potential of Mo-CBP2 as a promising molecule with low toxicity and potent activity. Further studies should be performed to better understand its mode of action and toxicity.

Ethnobotanic, phytochemical uses and ethnopharmacological profile of genus Cnidoscolus spp. (Euphorbiaceae): A comprehensive overview.

The application of medicinal plants are the most important biotechnological alternative in the treatment of numerous diseases, especially in developing countries, such as Brazil. Among them, we specified some specimens of the genus Cnidoscolus used as phytotherapies, with healing properties, analgesic, anti-inflammatory, antibiotic and diuretic, anticancer, among others. Such effects are possibly associated with the presence of terpenoids, alkaloids, coumarins, flavonoids phenolic compounds, among others. Thus, the objective of this work was to evaluate in the literature the studies on the phytochemical, ethnopharmacological and biotechnological applications of this genus, from 1998 to 2017. Among the sixty-one studies reported in this review, ten species are popularly utilized to pharmacological and/or biotechnological applications. Cnidoscolus aconitifolius and Cnidoscolus chayamansa are the most cited species, which were also supported by either animal or cellular investigations indicating some beneficial pharmacological actions like antioxidant, anti-inflammatory and potential cytotoxic activity. The plant parts of this genus under study are important as sources for the isolation and identification of bioactive molecules with biotechnological applications, among the many diseases treated with this phytotherapy. Given these verdicts, ethnopharmacological approaches are significant systematic tools in the determination of plant species that exhibit medicinal and nutritional purposes. The results presented here should further stimulate the development of validation studies to ensure the safe and effective use of these plant species.