Anti-leishmanial Activities of Extracts and Isolated Compounds from Drechslera rostrata and Eurotium tonpholium

Antiprotozoal potential of Vismia species (Hypericaceae), medicinal plants used to fight cutaneous leishmaniasis

ETHNOPHARMACOLOGICAL RELEVANCE

Species of Vismia (Hypericaceae), known in Brazil as "lacre", are commonly used in traditional Amazonian medicine for the treatment of skin lesions, including those caused by Leishmania infection.

AIM OF THE STUDY

Hexane extracts from the leaves of Vismia cayennensis, V. gracilis, V. sandwithii and V. guianensis, as well as from the fruits of the latter, in addition to the anthraquinones vismiaquinone, physcion and chrysophanol isolated from these species were explored for their anti-promastigote and anti-amastigote activity on Leishmania amazonensis.

MATERIALS AND METHODS

Extracts were prepared by static maceration with n-hexane. The compounds, isolated by chromatographic techniques, were identified by spectroscopic methods (1H and 13C NMR). Promastigotes of L.amazonensis were incubated with hexane extracts (1-50 μg/mL) or anthraquinones (1-50 μM) and the parasite survival analyzed. The action of compounds on reactive oxygen species (ROS) production, mitochondrial membrane potential, and membrane integrity of promastigotes were evaluated by flow cytometer, and the cytotoxicity on mammalian cells using MTT assay. Furthermore, the activity of compounds against amastigotes and nitric oxide production were also investigated.

RESULTS

Vismiaquinone and physcion were obtained from the leaves of V. guianensis. Physcion, as well as chrysophanol, were isolated from V. sandwithii. Vismia cayennensis and V. gracilis also showed vismiaquinone, compound detected in lower quantity in the fruits of V. guianensis. All extracts were active against the parasite, corroborating the popular use. The greatest activity against promastigotes was achieved with V. guianensis extract (IC50 4.3 μg/mL), precisely the most used Vismia species for treating cutaneous leishmaniasis. Vismiaquinone and physcion exhibited relevant activity with IC50 12.6 and 2.6 μM, respectively. Moreover, all extracts and anthraquinones tested induced ROS production, mitochondrial dysfunction, membrane disruption and were able to kill intracellular amastigote forms, being worthy of further in vivo studies as potential antileishmanial drugs.

CONCLUSIONS

The overall data achieved in the current investigation scientifically validate the traditional use of Vismia species, mainly V. guianensis, as an anti-Leishmania agent. Furthermore, the promising results presented here indicate species of Vismia as potentially useful resources of Brazilian flora for the discovery of therapeutic solutions for neglected diseases.

Antibacterial and β-amyloid precursor protein-cleaving enzyme 1 inhibitory polyketides from the fungus Aspergillus chevalieri

One new prenylated benzenoid, (±)-chevalieric acid (1), and four new anthraquinone derivatives, (10S,12S)-, (10S,12R)-, (10R,12S)-, and (10R,12R)-chevalierone (2-5), together with ten previously described compounds (6-15), were isolated from the fungus Aspergillus chevalieri (L. Mangin) Thom and Church. The structures of new compounds were elucidated by extensive 1D and 2D nuclear magnetic resonance (NMR), and HRESIMS spectroscopic analysis. The absolute configurations of 2-5 were determined by experimental and calculated electronic circular dichroism (ECD) and DP4+ analysis. Compound 10 showed weak cytotoxicity against human lung cancer cell line A549 with IC50 39.68 μM. Compounds 2-5 exhibited antibacterial activities against the methicillin-resistant Staphylococcus aureus (MRSA) and opportunistic pathogenic bacterium Pseudomonas aeruginosa. The MIC value for compound 6 against MRSA is 44.02 μM. Additionally, Compounds 8, 10, 11 showed weak to moderate inhibitory activities against the β-secretase (BACE1), with IC50 values of 36.1, 40.9, 34.9 μM, respectively.

Anethum sowa Roxb. ex fleming: A review on traditional uses, phytochemistry, pharmacological and toxicological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Anethum sowa Roxb. ex Fleming (Syn. Peucedanum sowa Roxb. ex Fleming, Family: Apiaceae) is a pharmacologically important as aromatic and medicinal plant. Various parts of this plant are used in traditional medicine systems for carminative, uterine and colic pain, digestion disorder, flatulence in babies, appetite-stimulating agent and used to treat mild flue and cough. The essential oil is used for aromatherapy. It is also used as a spice for food flavouring and culinary preparations in many Asian and European countries.

AIM OF THE REVIEW

This review aims to provide a comprehensive and critical assessment from the reported traditional and pharmaceutical uses and pharmacological activities of the extracts, essential oil and phytoconstituents with emphasis on its therapeutic potential as well as toxicological evaluation of A. sowa.

MATERIALS AND METHODS

Online search engines such as SciFinder®, GoogleScholar®, ResearchGate®, Web of Science®, Scopus®, PubMed and additional data from books, proceedings and local prints were searched using relevant keywords and terminologies related to A. sowa for critical analyses.

RESULTS

The literature studies demonstrated that A. sowa possesses several ethnopharmacological activities, including pharmaceutical prescriptions, traditional applications, and spice in food preparations. The phytochemical investigation conducted on crude extracts has been characterized and identified various classes of compounds, including coumarins, anthraquinone, terpenoids, alkaloid, benzodioxoles, phenolics, polyphenols, phenolic and polyphenols, fatty acids, phthalides and carotenoids. The extracts and compounds from the different parts of A. sowa showed diverse in vitro and in vivo biological activities including antioxidant, antiviral, antibacterial, analgesic and anti-inflammatory, Alzheimer associating neuromodulatory, cytotoxic, anticancer, antidiabetes, insecticidal and larvicidal.

CONCLUSION

A. sowa is a valuable medicinal plant which is especially used in food flavouring and culinary preparations. This review summarized the pertinent information on A. sowa and its traditional and culinary uses, as well as potential pharmacological properties of essential oils, extracts and isolated compounds. The traditional uses of A. sowa are supported by in vitro/vivo pharmacological studies; however, further investigation on A. sowa should be focused on isolation and identification of more active compounds and establish the links between the traditional uses and reported pharmacological activities with active compounds, as well as structure-activity relationship and in vivo mechanistic studies before integrated into the medicine. The toxicological report confirmed its safety. Nonetheless, pharmacokinetic evaluation tests to validate its bioavailability should be encouraged.

The Effects of Silver Nanoparticles Biosynthesized Using Fig and Olive Extracts on Cutaneous leishmaniasis Induced Inflammation in Female Balb/c Mice

Leishmaniasis is a group of infectious and non-contagious severe parasitic diseases, caused by protozoans of the Leishmania genus. Natural products characterize a rich source of prospective chemical entities for the development of new effective drugs for neglected diseases. Scientific evaluation of medicinal plants has made it possible to use some metabolites from flavonoids and polyphenols compounds for the treatment of parasitic diseases. Therefore, we aimed in this study to evaluate the protective effect of Silver nanoparticles (Ag-NPs) biosynthesized using Fig and Olive extracts (NFO) against Cutaneous leishmaniasis in female Balb/c mice. A total of 70 mice were used and divided into seven groups. Treatment was initiated when local lesions were apparent, we found Fig and Olive extracts were found to be a good source for the synthesis of (Ag-NPs), their formation was confirmed by color change and stability in solution. Nanoparticles biosynthesized using Fig and Olive extracts induced a reduction in the average size of cutaneous leishmaniasis lesions compared with the untreated mice. Moreover, nanoparticles treatment decreased oxidative stress (LPO, NO), down regulation gene expression levels (TNF-α, IL-1β and BAX) and this antileishmanial activity of nanoparticles was associated with enhanced antioxidant enzyme activities. In addition, histopathological evaluation proved the antileishmanial activity of nanoparticles compared to the positive control. Therefore, we aimed in this study to evaluate the protective effect of silver nanoparticles biosynthesized using Fig and Olive extracts against cutaneous lesions induced by Leishmania major infection through their anti-inflammatory, antioxidant activities and faster clinical efficacy than standard pentavalent antimonial treatment.

Fungal Pigments: Potential Coloring Compounds for Wide Ranging Applications in Textile Dyeing

Synthetic pigments/non-renewable coloring sources used normally in the textile industry release toxic substances into the environment, causing perilous ecological challenges. To be safer from such challenges of synthetic colorants, academia and industries have explored the use of natural colorants such as microbial pigments. Such explorations have created a fervent interest among textile stakeholders to undertake the dyeing of textile fabrics, especially with fungal pigments. The biodegradable and sustainable production of natural colorants from fungal sources stand as being comparatively advantageous to synthetic dyes. The prospective scope of fungal pigments has emerged in the opening of many new avenues in textile colorants for wide ranging applications. Applying the biotechnological processes, fungal pigments like carotenoids, melanins, flavins, phenazines, quinones, monascins, violacein, indigo, etc. could be extracted on an industrial scale. This review appraises the studies and applications of various fungal pigments in dyeing textile fabrics and is furthermore shedding light on the importance of toxicity testing, genetic manipulations of fungal pigments, and their future perspectives under biotechnological approaches.

Metabolites of a Drechslera sp. endophyte with potential as biocontrol and bioremediation agent

Endophytic fungi have several well-established beneficial effects on plant health and growth, and are a huge source of bioactive compounds. The endophyte Drechslera sp. strain 678, isolated from the roots of an Australian native grass Neurachne alopecuroidea, demonstrated efficacy against four plant pathogens (Pythium ultimum, Rhizoctonia solani, Botrytis cinerea, Alternaria alternata). In addition, strain 678 was capable of degrading a common additive used in gasoline, known as methyl tertiary-butyl ether (MtBE). Thus, the organic extracts obtained from the culture filtrate of strain 678 were studied. Metabolomic analysis revealed the presence of two major bioactive metabolites, monocerin and an alkynyl substituted epoxycyclohexenone derivative, which showed good antifungal activity. The Drechslera sp. strain 678 and its compounds show promise for applications in biocontrol and bioremediation activities in agriculture or as a remediation option for MtBE contamination in soil.

Metabolites from the Dark Septate Endophyte Drechslera sp. Evaluation by LC/MS and Principal Component Analysis of Culture Extracts with Histone Deacetylase Inhibitors

Secondary metabolites from the cultures of the dark septate fungal endophyte (DSE) Drechslera sp., isolated from the roots of rye grass (Lollium sp.) and cultured under different experimental conditions, are described here for the first time. The use of suberoylanilidehydroxamic acid (SAHA) and other histone deacetylase inhibitors as epigenetic modifiers in the culture medium was evaluated by LC/MS and LC/MS/MS. Several differences in the metabolite production were detected by means of supervised principal component analysis (PCA) of LC/MS data. The presence of the compounds in the culture medium or in the mycelium was compared. In order to confirm their structure, many of these natural products were isolated from a larger scale culture. These metabolites were characterized as prenylhydroxybenzoic acids and chromans, two compounds, one of each class were previously undescribed, prenylquinoids, diketopiperazines and macrosphelides. Some of the compounds, which were released to the medium, showed good antifungal activity, suggesting that these compounds could protect Lollium from fungal phytopatogens. The use of SAHA as an additive of the cultures also induced the release of hexosylphytosphyngosine to the culture medium. The biotransformation of the inhibitors was observed in addition to the production of antifungal metabolites, showing the ability of this endophytic strain to control xenobiotics.

Antitumor activity of extract and isolated compounds from Drechslera rostrata and Eurotium tonophilum

Total extracts of Drechslera rostrata and Eurotium tonophilum in addition of two isolated compounds from their cultures [di-2-ethylhexyl phthalate (H1) and 1,8-Dihydroxy-3-methoxy-6-methyl-anthraquinone (H2)] were tested for their antitumor activity using four human carcinoma cell lines. Antitumor activity was assessed by performing MTT assay to check the % cell viability. The % viability of HCT-116 (colon carcinoma), HeLa (cervical carcinoma), HEp-2 (larynx carcinoma) and HepG-2 (hepatocellular carcinoma) cells decreased after treatment with Drechslera rostrata and Eurotium tonophilum extracts, these effects were ranged from 059.0 ±  0.1 to 217.0  ±  0.3 µg/ml on all types of cancer cells. The best activity was recorded for Eurotium tonpholium extract (054.5 ± 0.3, 059.0 ± 0.5 and 059.0 ± 0.1 for HEp-2, Hela, and HepG-2 respectively). The isolated compounds (H1&H2) were found to be responsible about the activities because they recorded the lowest IC₅₀ on tested cell lines with range of 9.5-20.3 μg/ml. Vinblastine sulphate was used as a reference standard and showed in vitro anticancer activity. This study demonstrated that all extracts and isolated compounds have antitumor activity against HCT-116, HeLa, HEp-2 and HepG-2 cells.

Biological activities of the red algae Galaxaura rugosa and Liagora hawaiiana butters

The biological activities; antimicrobial, antioxidant and anticancer, of the red algae Galaxaura rugosa and Liagora hawaiiana were determined. The total ethanol, lipoidal matters, chloroform, n-butanol, aqueous extracts and powder of both algae showed and bacterial and antifungal activities. However, the chloroform extract of Galaxaura rugosa showed antibacterial activity against Klebsiella pneumoniae (24 mm, 0.15 mg/ml) higher than gentamycin (23 mm, 0.49 mg/ml). Moreover, the total ethanol, lipoidal matter and chloroform extracts showed antifungal activity (21, 22 and 25 mm, 1.25, 0.312 and 0.156 mg/ml) similar to the antibiotic Ketoconazole activity (23, 24 and 27 mm, 1.25, 0.312 and 0.156 mg/ml) against Aspergillus fumigatus, A. niger and Candida trobicalis, respectively. A good antioxidant activity (80.96%, IC₅₀ = 27.8 µg/ml) was provided by Galaxaura rugosa. The anticancer activity results revealed that the lipoidal matters of Galaxaura rugosa and Liagora hawaiiana possessed antitumor activity (IC₅₀ = 15 ± 1.7 and 21.2 ± 1.6, respectively) against lung carcinoma (A-549) better than vinblastine sulfate (IC₅₀ = 24.6 ± 0.7). Although, the lipoidal matters of Galaxaura rugosa and Liagora hawaiiana antitumor activity against cervical carcinoma (HeLa) and intestinal carcinoma (CACO-2) (IC₅₀ = 10.2 ± 0.6 and 12.2 ± 0.6, respectively) preferable than vinblastine sulfate (IC₅₀ = 59.7 ± 2.1 and 30.3 ± 1.4, respectively).

Anticandidal Activity of Extracts and a Novel Compound, Amnomopin, Isolated From Petriella setifera

A novel triterpenoidal compound named 'amnomopin' (3β-diglucoside-5,12-28-oic acid), which is named IUPAC as 3-O-(2' ➔ 1″diglucoside)1,2,3,4,4a,5,6,6a,6b,7,9,10,11,12,12a,12b,13,14b-octadecahydro-10-hydroxy-2,2,6a,6b,9,9,12a-heptamethylpicene-4a-carboxylic acid, was isolated from the extract Petriella setifera. The total alcoholic extract of P. setifera showed a great activity against clinically isolated Candida species, including Candida albicans, Candida dubliniensis, Candida famata, Candida glabrata, Candida inconspicua, Candida kefyr, Candida krusei, Candida norvegensis, Candida parapsilosis and Candida tropicalis. Also, the new compound amnomopin was active against all the investigated Candida species. The highest anticandidal activity of P. setifera extract was obtained against C. kefyr (22.6 ± 1.5 mm), C. albicans and C. norvegensis (21.3 ± 0.63 mm) and C. krusei (20.6 ± 1.5 mm). Moreover, the minimum inhibitory concentrations of both the total extract and the isolated compound were low. The minimum inhibitory concentration of the compound isolated from P. setifera was 0.49 μg/mL against C. kefyr, 0.98 μg/mL against C. albicans and C. norvegensis and 1.95 μg/mL against C. krusei. The oral dosing of the extract and the isolated compound did not show any significant effect on the activity of alanine aminotransferase, aspirate aminotransferase and the levels of blood urea and serum creatinine. Copyright © 2017 John Wiley & Sons, Ltd.

An 8-hydroxyquinoline-containing polymeric micelle system is effective for the treatment of murine tegumentary leishmaniasis

The current treatment of leishmaniasis has been hampered due to the high toxicity of the available drugs and long duration protocols, which often lead to its abandonment. In the present study, a poloxamer 407-based delivery system was developed, and a molecule, 8-hydroxyquinoline (8-HQN), was incorporated with it, leading to an 8-HQN/micelle (8-HQN/M) composition. Assays were performed to evaluate the in vitro antileishmanial activity of 8-HQN/M against Leishmania amazonensis stationary promastigotes. The cytotoxicity in murine macrophages and in human red cells, as well as the efficacy of the treatment in macrophages infected by parasites, was also assessed. This product was also evaluated for the treatment of murine tegumentary leishmaniasis, using L. amazonensis-infected BALB/c mice. To evaluate the in vivo efficacy of the treatment, the average lesion diameter (area) in the infected tissue, as well as the parasite load at the site of infection (skin), spleen, liver and draining lymph nodes were examined. Non-incorporated micelle (B-8-HQN/M) and the free molecule (8-HQN) were used as controls, besides animals that received only saline. The parasite burden was evaluated by limiting dilution and quantitative real-time PCR (qPCR) techniques, and immunological parameters associated with the treatments were also investigated. In the results, the 8-HQN/M group, when compared to the others, presented more significant reductions in the average lesion diameter and in the parasite burden in the skin and all evaluated organs. These animals also showed significantly higher levels of parasite-specific IFN-γ, IL-12, and GM-CSF, associated with low levels of IL-4 and IL-10, when compared to the saline, 8-HQN/M, and B-8-HQN groups. A predominant IL-12-driven IFN-γ production, against parasite proteins, mainly produced by CD4⁺ T cells, was observed in the treated animals, post-infection. In conclusion, 8-HQN/M was highly effective in treating L. amazonensis-infected BALB/c mice and can be considered alone, or combined with other drugs, as an alternative treatment for tegumentary leishmaniasis. Graphical Abstract Therapeutic scheme and immunological and parasitological parameters developed in the present study.

Anthraquinones and Derivatives from Marine-Derived Fungi: Structural Diversity and Selected Biological Activities

Anthraquinones and their derivatives constitute a large group of quinoid compounds with about 700 molecules described. They are widespread in fungi and their chemical diversity and biological activities recently attracted attention of industries in such fields as pharmaceuticals, clothes dyeing, and food colorants. Their positive and/or negative effect(s) due to the 9,10-anthracenedione structure and its substituents are still not clearly understood and their potential roles or effects on human health are today strongly discussed among scientists. As marine microorganisms recently appeared as producers of an astonishing variety of structurally unique secondary metabolites, they may represent a promising resource for identifying new candidates for therapeutic drugs or daily additives. Within this review, we investigate the present knowledge about the anthraquinones and derivatives listed to date from marine-derived filamentous fungi's productions. This overview highlights the molecules which have been identified in microorganisms for the first time. The structures and colors of the anthraquinoid compounds come along with the known roles of some molecules in the life of the organisms. Some specific biological activities are also described. This may help to open doors towards innovative natural substances.