Ensayo de citotoxicidad de extractos de Pleurotusostreatus en diferentes líneas celulares para aplicaciones inmunonutricionales

Introducción: Los bioderivados propuestos como candidatos a ingredientes alimentarios suelen requerir ciertas evaluaciones para las aplicaciones inmunonutricionales Los hongos comestibles-medicinales son un surtidor de compuestos con estas potencialidades. Entre ellos, las setas Pleurotus ostreatus contienen metabolitos bioactivos, con importantes usos en la industria alimenticia y en la práctica terapéutica de la industria médico-farmacéutica. Los ensayos de citotoxicidad in vitro constituyen métodos valiosos para evaluarproductos de origen natural, como los extractos fúngicos. Objetivo: Evaluar la citotoxicidad de dos extractos obtenidos de la seta Pleurotus ostreatus en diferentes líneas celulares. Método: Se obtuvieron extractos hidrosolubles a partir del micelio y de los cuerpos fructíferos de Pleurotus ostreatus en laboratorios del Centro de Estudios de Biotecnología Industrial de la Universidad de Oriente. Se evaluó la citotoxicidad de los bioproductos por el ensayo de reducción del colorante resazurina sobre tres líneas celulares en el Laboratorio de Microbiología, Parasitología e Higiene (LMPH) de la Universidad de Amberes, Bélgica. Se utilizaron células no adherentes THP-1 (pre-monocitos de leucemia humana), células adherentes Caco-2 (epitelio de adenocarcinoma de colon humano) y células adherentes RAW 264.7 (macrófagos murinos). Resultados: Los extractos de Pleurotus ostreatus no resultaron citotóxicos para ninguna de las líneas celulares estudiadas humanas o murina, ya que no ocasionaron daños sobre la viabilidad de las célulasepiteliales del sistema gastrointestinal, nisobrelas células del sistema inmune empleadas. Conclusiones: Este resultado demuestra que ambos bioderivados fúngicos pueden ser aplicados con seguridad en estudios inmunonutricionales.

Introduction: Bioderivatives proposed as candidates for food ingredients usually require certain evaluations for immunonutritional applications. Edible-medicinal mushrooms are a source of compounds with these potentials. Among them, Pleurotus ostreatus mushrooms contain bioactive metabolites, with important uses in the food industry and in the therapeutic practice of the medical-pharmaceutical industry. In vitro cytotoxicity assays are valuable methods to evaluate products of natural origin, such as fungal extracts. Objective: To evaluate the cytotoxicity of two extracts obtained from the Pleurotus ostreatus mushroom in different cell lines. Method: Water-soluble extracts were obtained from the mycelium and fruiting bodies of Pleurotus ostreatus in laboratories of the Center for Industrial Biotechnology Studies of the Universidad de Oriente. The cytotoxicity of the bioproducts was evaluated by the resazurin dye reduction assay on three cell lines at the Laboratory of Microbiology, Parasitology and Hygiene (LMPH) of the University of Antwerp, Belgium. Non-adherent THP-1 cells (human leukemia pre-monocytes), Caco-2 adherent cells (human colon adenocarcinoma epithelium) and RAW 264.7 adherent cells (murine macrophages) were used. Results: Pleurotus ostreatus extracts were not cytotoxic for any of the human or murine cell lines studied, since they did not cause damage to the viability of the epithelial cells of the gastrointestinal system, nor to the immune system cells used. Conclusions: This result demonstrates that both fungal bioderivatives can be safely applied in immunonutritional studies.

Introdução: Bioderivados propostos como candidatos a ingredientes alimentícios geralmente requerem determinadas avaliações para aplicações imunonutricionais. Pleurotus ostreatus contêm metabólitos bioativos, com importantes utilizações na indústria alimentícia e na prática terapêutica da indústria médico-farmacêutica. Ensaios de citotoxicidade in vitro são métodos valiosos para avaliar produtos de origem natural, como extratos de fungos. Objetivo: Avaliar a citotoxicidade de dois extratos obtidos do cogumelo Pleurotus ostreatus em diferentes linhagens celulares. Método: Extratos hidrossolúveis foram obtidos do micélio e dos corpos frutíferos de Pleurotus ostreatus nos laboratórios do Centro de Estudos de Biotecnologia Industrial da Universidade de Oriente. A citotoxicidade dos bioprodutos foi avaliada pelo ensaio de redução do corante resazurina em três linhagens celulares no Laboratório de Microbiologia, Parasitologia e Higiene (LMPH) da Universidade de Antuérpia, Bélgica. Foram utilizadas células THP-1 não aderentes (pré-monócitos de leucemia humana), células aderentes Caco-2 (epitélio de adenocarcinoma do cólon humano) e células aderentes RAW 264.7 (macrófagos murinos). Resultados: Os extratos de Pleurotus ostreatus não foram citotóxicos para nenhuma das linhagens celulares humanas ou murinas estudadas, pois não causaram danos à viabilidade das células epiteliais do sistema gastrointestinal, nem às células do sistema imunológico utilizadas. Conclusões: Este resultado demonstra que ambos os bioderivados fúngicos podem ser aplicados com segurança em estudos imunonutricionais.

Anti-infective, cytotoxic and antioxidant activity of Ziziphus oxyphylla and Cedrela serrata

Objective: To search for the most active antimicrobial and antioxidant sub-fractions related to traditional use of Ziziphus oxyphylla (Z. oxyphylla) and Cedrela serrata (C. serrata) in Pakistan against infectious and liver diseases. Methods: Factions of different polarity were tested in vitro for their antiprotozoal, antimalarial, antibacterial and antifungal activity against different pathogens. Cytotoxicity on MRC-5 cell lines (human lung fibroblasts) as well as, in vitro radical scavenging activity was evaluated using the 1, 1-diphenyl-2-picrylhydrazyl radical assay. Results: The highest antiprotozoal activity was observed for the CHCl3 fractions of Z. oxyphylla roots and leaves, and C. serrata bark. The CHCl3 and EtOAc fractions of Z. oxyphylla roots, the CHCl3 fraction of Z. oxyphylla leaves, the EtOAc and the residual MeOH: H2O fraction of C. serrata bark showed antibacterial activity against Staphylo-coccus aureus. The same residual MeOH: H2O fraction of C. serrata bark was active against Candida albicans. The highest antioxidant activity was observed for the more hydrophilic EtOAc fractions of Z. oxyphylla leaves, C. serrata bark and leaves, and the residual MeOH:H2O fraction of C. serrata bark. Conclusions: This study supports at least in part the traditional uses of these plants for antimicrobial purposes and against liver diseases.

In vitro antimicrobial assessment of Cuban propolis extracts

Propolis is a resinous mixture of different plant exudates collected by honeybees. Currently, propolis is widely used as a food supplement and in folk medicine. We have evaluated 20 Cuban propolis extracts of different chemical types, brown (BCP), red and yellow (YCP), with respect to their in vitro antibacterial, antifungal and antiprotozoal properties. The extracts inhibited the growth of Staphylococcus aureus and Trichophyton rubrum at low µg/mL concentrations, whereas they were not active against Escherichia coli and Candida albicans. The major activity of the extracts was found against the protozoa Leishmania, Trypanosoma and Plasmodium, although cytotoxicity against MRC-5 cells was also observed. The BCP-3, YCP-39 and YCP-60 extracts showed the highest activity against P. falciparum, with 50% of microbial growth (IC50) values of 0.2 µg/mL. A positive correlation between the biological activity and the chemical composition was observed for YCP extracts. The most promising antimicrobial activity corresponds to YCP subtype B, which contains acetyl triterpenes as the main constituents. The present in vitro study highlights the potential of propolis against protozoa, but further research is needed to increase selectivity towards the parasite. The observed chemical composition-activity relationship of propolis can contribute to the identification of the active principles and standardisation of this bee product.

In vitro anti-microbial activity of the Cuban medicinal plants Simarouba glauca DC, Melaleuca leucadendron L and Artemisia absinthium L

In the present study, an extensive in vitro antimicrobial profiling was performed for three medicinal plants grown in Cuba, namely Simarouba glauca, Melaleuca leucadendron and Artemisia absinthium. Ethanol extracts were tested for their antiprotozoal potential against Trypanosoma b. brucei, Trypanosoma cruzi, Leishmania infantum and Plasmodium falciparum. Antifungal activities were evaluated against Microsporum canis and Candida albicans whereas Escherichia coli and Staphylococcus aureus were used as test organisms for antibacterial activity. Cytotoxicity was assessed against human MRC-5 cells. Only M. leucadendron extract showed selective activity against microorganisms tested. Although S. glauca exhibited strong activity against all protozoa, it must be considered non-specific. The value of integrated evaluation of extracts with particular reference to selectivity is discussed.