ABSTRACT
BACKGROUND: H2S is proved to be functioning as a signaling molecule in an array of physiological processes in the plant and animal kingdom. However, the H2S synthesis pathway and the responses to cold conditions remain unclear in postharvest mushroom. RESULTS: The biosynthesis of H2S in the Agaricus bisporus mushroom tissues exhibited an increasing tendency during postharvest storage and was significantly triggered by cold treatment. The cystathionine clyase (AbCSE) and cystathionine b-synthase (AbCBS) genes were cloned and proved responsible for H2S biosynthesis. Furthermore, transcriptional and posttranscriptional regulation of AbCSE and AbCBS were crucial for the enzyme activities and subsequent H2S levels. However, the AbMST was not involved in this process. Moreover, the AbCSE and AbCBS genes displayed low identity to the characterized genes, but typical catalytic domains, activity sites, subunit interface sites, and cofactor binding sites were conserved in the respective protein sequences, as revealed by molecular modeling and docking study. The potential transcription factors responsible for the H2S biosynthesis in cold conditions were also provided. CONCLUSIONS: The H2S biosynthetic pathway in postharvest mushroom was unique and distinct to that of other horticultural products.
Subject(s)
Agaricus/chemistry , Cystathionine beta-Synthase/metabolism , Cystathionine gamma-Lyase/metabolism , Hydrogen Sulfide/chemical synthesis , Crop Production , Agaricus campestris , Cold Temperature , Food StorageABSTRACT
Los antioxidantes son esenciales en el cuerpo humano para prevenir el daño oxidativo. Estas sustancias pueden obtenerse de diferentes fuentes como frutas, plantas y hongos. En Guatemala, diversas especies de hongos comestibles son comercializadas y consumidas, sin embargo su actividad antioxidante no ha sido documentada en el país. El objetivo de este estudio fue determinar la actividad antioxidante de extractos acuosos y etanólicos obtenidos de diez especies de basidiomicetos comestibles (Agaricus aff. bisporus, Agaricus brunnescens, Armilla-riella polymyces, Amanita garabitoana, Boletus edulis, Cantharellus lateritius, Laccaria amethystina, Lactarius deliciosus, Neolentinus ponderosus y Pleurotus ostreatus). Se utilizó un método cualitativo por cromatografía en capa fina (CCF) y tres ensayos macrométricos in vitro de cuantificación de fenoles totales, reducción del radical 1,1-difenil-2-pricrilhidrazilo (DPPH) y decoloración del radical catiónico del reactivo ácido 2,2-azinobis-(acido-3-etilbenzotiazolina-6-sulfónico)(ABTS). Los extractos acuosos mostraron mayor actividad antioxidante que los extractos etanólicos en todas las técnicas cuantitativas realizadas. La especie que mostró mayor actividad antioxidante en ambos extractos fue B. edulis, cuyos resultados en el extracto acuoso fueron: fenoles totales 93.46 ± 18.17 mg/g, DPPH CI 50 0.93 mg/mL (IC95% 0.65-1.28) y en ABTS CI50 0.96 mg/mL (IC 95% 0.63-1.35); los resultados en el extracto etanólico fueron: Fenoles totales 42.70 ± 3.48 mg/g, DPPH CI50 2.75 mg/mL (IC 95% 2.46-3.07) y 4.13 mg/mL (IC 95% 2.67-5.88). Se evidencia de esta forma que las especies de basidiomicetos estudiadas presentan actividad antioxidante por lo cual pueden ser una fuente potencial de antioxidantes naturales.
Antioxidants are essential in the body to prevent oxidative damage. These antioxidant substances are obtained from different sources such as fruits, plants and mushrooms. In Guatemala, diverse species of mushrooms are commercialized and consumed, however their antioxidant activity has not been documented in Guatemala. The goal of this study aimed to determine the antioxidant activity of aqueous and ethanolic extracts obtained from edible basidiomycetes species: Agaricus aff. bisporus, A. brunnescens, Armillariella polymyces, Amanita garabitoana, Boletus edulis, Cantharellus lateritius, Laccaria amethystina, Lactarius deliciosus, Neolentinus ponderosus and Pleurotus ostreatus. Thin layer chromatography (TLC) was used as a qualitative method to determine the presence of antioxidant activity, subsequently, three in vitro macrometric assays were used: the quantification of total phenolics, reduction of 1,1-diphenyl-2-pricrilhidrazil (DPPH) radical, and discoloration of the acid reagent 2.2 -azinobis-(acid-3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation. Aqueous extracts exhibited higher antioxidant activity than ethanolic in all the quantitative techniques used. The specie that showed greater antioxidant activity in both extracts was B. edulis, whose results of aqueous extract were as follows: Total phenolics 93.46 ± 18.17 mg/g , DPPH IC50 0.93 mg/mL (CI95% 0.65-1.28) and ABTS IC50 0.96 mg/mL (CI95% 0.63-1.35); results of ethanolic extract were: Total phenolics 42.70 ± 3.48 mg/g, DPPH IC50 2.75 mg/mL (CI95% 2.46-3.07) and ABTS IC50 4.13 mg/mL (CI95% 2.67-5.88). Based in the result of the study all the basidiomycetes species that were evaluated have antioxidant activity, therefore, are potential sources of natural antioxidants.
Subject(s)
Humans , Male , Female , Agaricus campestris , Functional Food , AmanitaABSTRACT
Pleurotus sp "Florida" foi cultivado no município de Uberlândia, MG, durante o período de setembro de 1989 a abril de 1991, sendo os dados de produtividade obtidos de abril a setembro de 1990. Para o início do cultivo, as sementes foram obtidas no Instituto de Botânica de Säo Paulo e a partir dos cogumelos produzidos em Uberlândia foi mantido um banco de micélio em BDA e spawn feito com arroz em casca cozido. Para o substrato definitivo foi utilizada cana-de-açúcar triturada, mantida em compostagem por oito dias. Durante o cultivo, a temperatura oscilou entre 15,6 e 30,6ºC e a umidade relativa do ar foi mantida em torno de 90 por cento. A produçäo média foi de 9,9 por cento de cogumelos por quilo de composto utilizado. O teor médio de proteínas do cogumelo produzido foi de 16,78 por cento, de carboidratos 52,43 por cento e de minerais 4,34 por cento, em relaçäo ao peso seco