Micetismos: Parte 3: Síndromes tempranos gastrointestinales / Mycetisms Part 3: Early Gastrointestinal Syndromes

En esta Parte 3 de la serie de cuatro artículos sobre micetismos se analizan los síndromes tempranos con síntomas gastrointestinales que se caracterizan por presentar un período de latencia muy corto, de menos de 6 horas después de la ingestión de los macromicetos. Los restantes síndromes tempranos con sintomatología compleja serán tratados en la Parte 4 de la serie. Actualmente se conocen más de 200 especies responsables de síndromes gastrointestinales, pero en este trabajo se abordarán solamente diez ejemplos que involucran los géneros Boletus [Boletus satanas (o Rubroboletus satanas) y Boletus venenatus (o Neoboletus venenata)], Hypholoma, Agaricus (Agaricus xanthodermus), Omphalotus, Lactarius, Russula, Entoloma, Chlorophyllum (Chlorophyllum molybdetes) y Leucoprinus (Leucoprinus birnbaumii). Las toxinas involucradas en estos casos presentan gran variedad estructural, desde proteínas hasta terpenoides, en particular sesquiterpenoides y triterpenoides, vinilglicina, fenol y azocompuestos, pero todas generan la misma sintomatología. Estas sustancias y otros componentes químicos de los hongos suelen ser indigestos, con una susceptibilidad variable entre los consumidores. El tratamiento es de apoyo y es estrictamente para esos casos con cuadros más graves de deshidratación. Normalmente, los casos evolucionan favorablemente después de 12 a 48 horas. Se analizan los síntomas, las toxinas involucradas, los mecanismos de acción, cuando se conocen y las especies causantes de los micetismos.

This part 3 of the series of four articles on mushroom poisoning refers to early-onset gastrointestinal syndromes, which are characterized by a very short latency period of less than 6 hours after mushroom ingestion. The remaining early-onset syndromes with complex symptoms will be treated in Part 4 of the series. Currently, more than 200 species responsible for gastrointestinal syndromes are known, but in this paper only ten examples will be addressed involving the genera Boletus [e.g., Boletus satanas (or Rubroboletus satanas), and Boletus venenatus (or Neoboletus venenata)], Hypholoma, Agaricus (e.g., Agaricus xanthodermus), Omphalotus, Lactarius, Russula, Entoloma, Chlorophyllum (e.g., Chlorophyllum molybdetes), and Leucoprinus (e.g., Leucoprinus birnbaumii). The toxins involved in these cases have a great structural variety, from proteins to terpenoids, in particular sesquiterpenoids and triterpenoids, vinylglycine, phenol, and azocompounds, but all show the same symptoms. These substances and other mushroom chemical constituents are usually indigestible, with varying consumer susceptibility. The treatment is supportive and is strictly for those cases with more severe dehydration. Usually, the cases progress favourably after 12 to 48 hours.The symptoms, toxins involved, mechanisms of action when known, and the species of mushrooms responsible for the mycetisms are analysed.

Nesta parte 3 da série de quatro artigos sobre intoxicação por cogumelos são analisadas as síndromes precoces com sintomas gastrointestinais que se caracterizam por apresentar um período de latência muito curto, de menos de 6 horas, após a ingestão de cogumelos. As síndromes precoces restantes com sintomatologia complexa serão tratadas na Parte 4 da série. Atualmente, são conhecidas mais de 200 espécies responsáveis por síndromes gastrointestinais, mas neste trabalho serão abordados apenas dez exemplos que envolvem os gêneros Boletus [Boletus satanas (ou Rubroboletus satanas) e Boletus venenatus (ou Neoboletus venenata)], Hypholoma, Agaricus (Agaricus xanthodermus), Omphalotus, Lactarius, Russula, Entoloma, Chlorophyllum (Chlorophyllum molybdetes) e Leucoprinus (Leucoprinus birnbaumii). As toxinas envolvidas nestes casos têm uma grande variedade estrutural, desde proteínas até terpenóides, em particular sesquiterpenóides e triterpenóides, vinilglicina, fenol e azo compostos, mas todas apresentam a mesma sintomatologia. Essas substâncias e outros constituintes químicos dos cogumelos costumam ser indigestos, com uma suscetibilidade variável entre aqueles que os consomem. O tratamento é de suporte e é rigorosamente para esses casos com quadros mais graves de desidratação. Normalmente, os casos evoluem favoravelmente após 12 a 48 horas. São analisados os sintomas, as toxinas envolvidas, os mecanismos de ação, quando conhecidos, e as espécies de cogumelos responsáveis pelas intoxicações.

Wild Edible Mushrooms Depict a Dissimilar Biogeographical Distribution in Humid Forests of Cameroon

For millennia, wild edible mushrooms (WEM) had always been considered as substantial food and medicinal sources, for local communities, both Bantu and indigenous peoples. However, few information and sparse data are available on useful mushrooms of Cameroon. A study was undertaken to update the checklist of WEM in humid forests of Cameroon. From mushroom excursions, surveys and inventories, thousand fungal specimens were collected in situ, described and identified using key features and references. Wild edible mushrooms were recruited in three trophic groups. They denoted a dissimilar national biogeographical distribution. Saprophytes and Termitomyces were encountered throughout the country; ectomycorrhizal mushrooms occurred in forest clumps, only in three regions: South, Southeast and Southwest. 117 WEM were listed belonging to 17 families and 43 genera, including nearly 22 Termitomyces, 32 ectomycorrhizal and 63 saprophyte species. 15 WEM were also claimed to have medicinal properties. This vast mushroom diversity related to various specific habitats and ecological niches. Five fungal groups were considered as excellent edible. Amanita and Boletus species were seldom consumed. Most mushroom species were harvested solely for home consumption, with the exception of Termitomyces, the only marketed mushroom. In fine, the diversity of WEM was high but poorly known and valorized. To fulfill the Nagoya convention, it is recommended to pursue mycological inventory of macrofungi in Cameroon, including the use of molecular tools and to cultivate local wild edible saprophyte mushrooms.

Diversidad de hongos micorrícicos en bosques de Pinus caribaea en Poptún, Guatemala / Diversity of mycorrhizal fungi in Pinus caribaea forests in Poptún, Guatemala

Pinus caribaea var. hondurensis (Sénéc.) W. H. Barrett & Golfari es una especie mesoamericana cuyo hábitat natural en Guatemala se está reduciendo aceleradamente por deforestación, aumento de ganadería y producción de cultivos de subsistencia. Además, los hongos ectomicorrícicos asociados, fundamentales para su supervivencia, han sido muy poco estudiados. Este es un estudio descriptivo que contiene información acerca de la diversidad de hongos micorrícicos recolectados en rodales de P. caribaea del municipio de Poptún, Petén, durante los años 1997-1998 y 2013- 2016, del uso de algunos de esos hongos como inóculo micorrícico, de identificación molecular de dos especies de Lactarius y de importantes aspectos etnomicológicos locales. Se encontró que existen especies endémicas, como Boletus guatemalensis, predominancia de boletales y russulales, diversidad fúngica semejante a la del sureste del país, poco uso de hongos comestibles silvestres y el primer registro de Amanita persicina (anteriormente A. muscaria var. persicina) en las tierras bajas mayas de Guatemala, con importantes aportes etnomicológicos. Aunque la diversidad debe ser mucho mayor a la encontrada, es aconsejable proseguir las recolectas, la identificación taxonómica de las especies locales y promover la conservación y reforestación con esta singular especie de pino a nivel municipal

Pinus caribaea var. hondurensis (Sénéc.) W. H. Barrett & Golfari is a Mesoamerican species whose natural habitat in Guatemala is being quickly reduced by deforestation, increase of livestock and subsistence crops. The mycorrhizal fungi associated with them, fundamental for their survival, had not been studied before. In this study it is presented a short report of the ectomycorrhizal fungi diversity collected in the stands of P. caribaea in the village of Poptún, Petén, between the years 1997-1998 and 2013-2016. Endemic species, such as Boletus guatemalensis, and predominance of boletales and russulales, were found. The fungal diversity presents more similarities to the one found in the southeast of the country, compared to the diversity of the west highlands. The first record of Amanita persicina (previously A. muscaria var. persicina) in the Mayan lowlands of Guatemala is reported, as well as related important ethnomycological findings. Nevertheless, it is expected higher diversity in the area, therefore, further research is recommended, regarding the taxonomic identification of the different species and the conservation and reforestation of the area with this pine species

Decolorization technique optimization for Boletus edulis polysaccharides and the antioxidant activity / 中成药

AIM To optimize the decolorization technique for Boletus edulis polysaccharides and to evaluate the antioxidant activity.METHODS With decolorization temperature,resin consumption,polysaccharide concentration and decolorization time as influencing factors,decolorization rate and polysaccharide recovery rate as evaluation indices,orthogonal test was applied to optimizing the decolorization technique on the basis of single factor test.Then the antioxidant activity was determined by Fe2+ chelating power,hydroxyl free radical scavenging activity and reducing power tests.RESULTS The optimal conditions were determined to be 30 ℃ for decolorization temperature,7.5 g/100 mg polysaccharides for S8 resin consumption,1 g/L for polysaccharide concentration,and 2 h for decolorization time,the decolorization rate and polysaccharide recovery rate were 89.34％ and 49.26％,respectively.The polysaccharides demonstrated strong Fe2+ chelating power and hydroxyl free radical scavenging activity with weak Fe3+ reduction power.CONCLUSION This stable and reliable method can be used for the decolorization for Boletus edulis polysaccharides with good antioxidant activity.

Actividad antioxidante de extractos de diez basidiomicetos comestibles en Guatemala / Antioxidant activity of extracts of ten edible basidiomycetes in Guatemala

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 basidiomycete’s 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 basidiomycete’s species that were evaluated have antioxidant activity, therefore, are potential sources of natural antioxidants.

ITS Primers with Enhanced Specificity to Detect the Ectomycorrhizal Fungi in the Roots of Wood Plants

With universal primer ITS1-F, the specific DHJ2 primer was developed to detect the Ectomycorrhizal (ECM) root tips in soil and to identify the species of ECM fungi, as based on DNA sequences of rDNA stored in GeneBank of NCBI. This primer was designed with the common sites of rDNA of Amanita and Boletus, and was also designed with several DNA programs provided by NCBI. The DNA fragments synthesized by PCR were calculated to be 1,000 to 1,200 bps of DNA located to 18s to 28s rDNA to contain two variable sites of ITS, indicating much diversities for specific species or ecotypes of ECM fungi. The primer DHJ2 reacted with the genomic DNA's extracted from the tissues of basidiocarp at the rate of 73 of 80 fungi collected produced single bands with a 1,100 bps length. The DNA fragment synthesized with the genomic DNA that extracted from eight ECM tips of Pinus densiflora was confirmed and analysized to the rDNAs of ECM in full sequences, and informed to be a ECM fungal species in the forest.

Observations on the Ectomycorrhizal Roots Collected from the Bases of the Basiodiocarps in Chungbuk

Various types of ectomycorrihzal root were observed from the bases of the basidiocarps collected from the four different soils of WalAk Mt., JoRyeong Mt, MinJuJi Mt. and hills near Korea National University of Education; The dichotomous ectomycorrihzal roots were mainly found to be from the interactions of the Pinus roots with the basidiocarps of Boletus and Amanita species. The black single bat-like ectomycorrihzal roots with the darken rhizomorphic mycelia were mainly found to be from the interactions of the Quercus roots with the basidiocarps of Russula species. The pyramid and the monopodial-pinnate ectomycorrihzal roots were also found to be from the interactions of the Pinus and deciduous tree roots with the basidiocarps of Russula and Boletus species. The distinguished structures of the mantle and Hartig net in the cortex layers were observed to be from the roots related to the genus of Pinus in the anatomical sections. However, the aggregated (premeated) structures of mantle and Hartig net in the cortex layer were found to be in the black and bat-like ectomycorrihzal roots. The structures of cross section in the ectomycorrihzal roots, especially the roots related to the host-plants of Pinus, were observed to be different from those according to the fungal species of the basidiocarps collected. The ectomycorrihzal root not reported or confirmed by the anatomical sections were newly found to be from the bases of the basidocarps of Amanita castanopsidis, Boletus laetissimus, B. violaceofuscus, B. speciosus, Clitopilus prunulus, Leccinum rugosiceps, Russula. alboareolata, R. bella, Strobilomyces confusus, Tylropilus neofelleus, and T. plumbeoviolaceus. From the observations mentioned above, the various types of ectomycomhzal roots were speculated to be formed between the different host plants and the different species of basidiocarps.