Evaluation of Conditions to Improve Biomass Production by Submerged Culture of Ganoderma sp.

In the present investigation, the conditions for in vitro submerged culture of a native strain of Ganoderma sp. were evaluated. Different culture medium ingredients, inoculum concentrations, inoculation methods, configuration, and airflows were evaluated to improve biomass production. The addition of thiamine and olive oil to the culture medium increased biomass production, as well as inoculating 6.6 g/L since there are no significant differences in biomass growth according to inoculum origin (pre-inoculum, discs or with spores). The best configuration of the 3 L stirred tank bioreactor was using three impellers and a porous air diffuser of 0.25 volume per volume per minute (vvm), the dry biomass concentration was 22.6 g/L after 12 days of cultivation at 30 °C, much higher than other investigations. This study provides relevant information for pilot-scale production of this fungus for future secondary metabolites. The culture medium was optimized, and it was defined that the concentration and origin of the inoculum did not influence the growth of Biomass, but the aeration and the configuration of the system allowed the establishment of protocols for the cultivation of Ganoderma sp.

Evaluation of the Use of Elicitors for the Production of Antioxidant Compounds in Liquid Cultures of Ganoderma curtisii from Costa Rica.

The use of substances or conditions as elicitors can significantly increase the production of secondary metabolites. In this research, the effects of different elicitors on the production of antioxidant secondary metabolites were evaluated in a strain of Ganoderma sp. The elicitors tested were pH changes in different growth phases of the fungus (pH 3, 5.5 and 8), different concentrations of peptone as a nitrogen source (1 g/L and 10 g/L), and the addition of chemical agents to the culture medium (ethanol, growth regulators, and salts). The alkaline pH during the stationary phase and the high availability of nitrogen were effective elicitors, producing cultures with higher antioxidant activity (37.87 g/L and 43.13 g/L dry biomass) although there were no significant differences with other treatments.

Emetine and cephaeline content in plants of Psychotria ipecacuanha in Costa Rica / Contenido de emetina y cefaelina en plantas de Psychotria ipecacuanha en Costa Rica / Emetina e conteúdo de cephaelina em plantas de Psychotria ipecacuanha na Costa Rica

Abstract The objective of this study was to identify the emetic metabolites in different parts of the P. ipecacuanha, a plant with emetic properties. Partial phytochemical analysis was performed to determine the presence of emetine and cephaeline in leaves, stems and roots. Both alkaloids were detected in the three plant parts analyzed. Highest alkaloid content was found in roots (8.55 mg/g), followed by stems (4.05 mg/g), and the lowest was found in leaves (2.4 mg/g). The cephaeline content (8.35 mg/g) was higher than that of emetine (6.65 mg/g) in all the three organs analyzed. Toxicity analysis of the crude extract showed a LD50 of 500 mg/kg.

Resumen El objetivo de este estudio fue identificar los metabolitos eméticos en diferentes partes de P.ipecacuanha, una planta con propiedades eméticas. Se realizó un análisis fitoquímico parcial, donde se determinó la presencia de emetina y cefalina en hojas, tallos y raíces. Ambos alcaloides se detectaron en las tres partes de la planta analizadas. El mayor contenido de alcaloides se encontró en las raíces (8.55 mg/g), seguido de los tallos (4.05 mg /g), y el más bajo se encontró en las hojas (2.4 mg/g). El contenido de cefalina (8,35 mg/g) fue mayor que el de emetina (6,65 mg/g) en los tres órganos analizados. El análisis de toxicidad del extracto crudo mostró una DL50 de 500 mg/kg.

Resumo O objetivo deste estudo foi identificar os metabólitos eméticos em diferentes partes do P. ipecacuanha, uma planta com propriedades eméticas. Foi realizada análise fitoquímica parcial para determinar a presença de emetina e cefelina nas folhas, caules e raízes. Ambos os alcalóides foram detectados nas três partes da planta analisadas. O maior teor de alcalóides foi encontrado nas raízes (8,55 mg/g), seguido dos caules (4,05 mg/g), e o menor foi encontrado nas folhas (2,4 mg/g). O conteúdo de cefhaelina (8,35 mg/g) foi superior ao de emetina (6,65 mg/g) nos três órgãos analisados. A análise de toxicidade do extrato bruto mostrou um LD50 de 500 mg/kg.

Seasonality effect on the composition of oxindole alkaloids from distinct organs of Uncaria tomentosa from the Caribbean region of Costa Rica.

Uncaria tomentosa (Willd.) D.C. (Rubiaceae), commonly known as "Uña de Gato" or "Cat's Claw", is a tropical vine from the rainforest used in traditional medicine and spread through Central and South America, including Costa Rica. There is an increasing demand for medicinal extracts with biological activity attributed mainly to oxindole alkaloids (OA), where the ratio between tetracyclic (TOA) and pentacyclic oxindole alkaloids (POA) determines its feasibility for medicinal applications. The ratio is affected by distinct factors including the dynamics of environmental conditions during seasons. The purpose of the study was to assess the seasonality effect in oxindole alkaloids content in relation to plant organs from U. tomentosa grown in the Caribbean region of Costa Rica. Young leaves followed by mature leaves presented the highest amount of total OA during seasons; for these, isoryncophylline, pteropodine and isomitraphylline, were the predominant OA. The POA/TOA ratio of both leaf materials was nearly 1:1 (3.2 mg g-1: 3.1 mg g-1). Bark and root material showed a pentacyclic chemotype in all seasons with a ratio of 6:1 (6.7 mg g-1: 1.3 mg g-1) with pteropodine and isomitraphylline as the predominant POA. The POA content presented seasonality with a significant increase from rainy to dry season in young leaves, bark and roots. In contrast, TOA amount remained virtually unchanged in all plant parts. Humidity and temperature between the studied seasons were constant except for precipitation, reflecting that differences of water content had an effect in the POA amounts. Further studies of abiotic factors, like water stress, could explain the variation of POA content due to seasonality.