Obtaining monokaryotic and dikaryotic mycelial cultures of two Amazonian strains of Geastrum (Geastraceae, Basidiomycota)

The high diversity of the genus Geastrum and the difficulty of obtaining mycelial cultures impairs the study of the ecophysiology and the exploration of the biotechnological potential of the taxon. In this study, different culture media were tested to obtain mycelial cultures for G. lloydianum and G. subiculosum collected in the Brazilian Amazon. Data on spore germination, and isolation of monokaryotic cultures and in vitro sexual reproduction are presented, as well as a brief morphological description of the cultures obtained. For both species, Potato Dextrose Agar (PDA) was the most promising of the tested culture media. The highest growth in agar culture ever recorded for this genus is reported (4.9 mm per week for G. lloydianum and 7.5 mm for G. subiculosum). In the PDA culture medium, spores germinated after 35-40 days of incubation and the isolation of monokaryotic cultures of the two species, as well as in vitro sexual crosses, were successfully performed. (AU)

Use of P450 cytochrome inhibitors in studies of enokipodin biosynthesis

Enokipodins A, B, C, and D are antimicrobial sesquiterpenes isolated from the mycelial culture medium of Flammulina velutipes, an edible mushroom. The presence of a quaternary carbon stereocenter on the cyclopentane ring makes enokipodins A-D attractive synthetic targets. In this study, nine different cytochrome P450 inhibitors were used to trap the biosynthetic intermediates of highly oxygenated cuparene-type sesquiterpenes of F. velutipes. Of these, 1-aminobenzotriazole produced three less-highly oxygenated biosynthetic intermediates of enokipodins A-D; these were identified as (S)-(-)-cuparene-1,4-quinone and epimers at C-3 of 6-hydroxy-6-methyl-3-(1,2,2-trimethylcyclopentyl)-2-cyclohexen-1-one. One of the epimers was found to be a new compound.

Daldinia eschscholtzii (Ascomycota, Xylariaceae) isolated from the Brazilian Amazon: taxonomic features and mycelial growth conditions / Daldinia eschscholzii (Ascomycota, Xylariaceae) isolado na Amazônia brasileira: características taxonômicas e condições de crescimento micelial

The Amazon has a high diversity of fungi, including species of the genus Daldinia (Ascomycota, Xylariaceae), which produce secondary metabolites with recognized nematicidal and antimicrobial activity. The ecological role of Daldinia is important, as stromata serve as refuges to many insects and arthropodes, and the fungi contribute to the degradation of vegetable organic matter. The aim of this study was to analyze the taxonomic features and mycelial growth conditions in vitro of a Daldinia specimen collected in the Brazilian Amazon. Morphological and molecular studies of the fungus identified it as D. eschscholtzii. To evaluate mycelial growth, we cultivated the fungus at 20, 25, 30, 35, and 40 °C in malt extract-peptone agar (MEPA), malt extract-peptone (MEP), potato dextrose (PD), and minimum medium (MM). The best mycelial growth occurred at 35 °C, although the greatest amount of biomass was obtained at 25 °C and 30 °C. PD proved to be the best medium for biomass production.

A Amazônia apresenta alta diversidade de fungos, incluindo Daldinia (Ascomycota, Xylariaceae), cujas espécies produzem metabólitos secundários com reconhecida atividade antimicrobiana e nematicida. O papel ecológico é importante, visto que estromas servem de abrigo para muitos insetos e artrópodes, além de contribuir na degradação da matéria orgânica vegetal. O objetivo desse estudo foi analizar as características taxonômicas e as condições do crescimento micelial in vitro de um espécime de Daldinia coletado na Amazônia brasileira. Estudos morfológicos e moleculares do fungo o indetificaram como D. eschscholtzii. Para avaliação do crescimento micelial o fungo foi cultivado nas temperaturas de 20, 25, 30, 35 e 40 °C e nos meios de cultura extrato de malte-peptona ágar (EMPA), extrato de malte-peptona (EMP), batata dextrose (BD) e meio mínimo (MM). O melhor crescimento micelial ocorreu a 35 °C, entretanto, a maior quantidade de biomassa foi obtida a 25 e 30 °C. O meio BD provou ser o melhor meio para produção de biomassa.

Percepção e compreensão dos conceitos contidos na Escala Brasileira de Insegurança Alimentar, em comunidades indígenas no estado do Amazonas, Brasil / Perception and comprehension of concepts of the Brazilian Food Insecurity Scale in indigenous communities in the state of Amazonas, Brazil

OBJETIVO: Este estudo teve como objetivo avaliar a percepção e a compreensão de conceitos e terminologia da segurança e insegurança alimentar, especialmente os que compõem a Escala Brasileira de Insegurança Alimentar, no contexto da realidade sócio-cultural indígena. MÉTODOS: Foram utilizados recursos de pesquisa qualitativa para a abordagem das comunidades indígenas Cacau, Flexeira e Mamori, situadas na bacia hidrográfica do Médio Juruá, nos municípios de Envira e Eirunepé (AM), baseando-se em metodologia já previamente utilizada no Brasil e adaptada ao presente contexto, em uma reunião com especialistas da área. Em seguida foram organizados grupos focais, com 18 participantes das três comunidades indígenas. RESULTADOS: A fome apareceu como situação vivenciada por muitos dos participantes dos grupos focais das três comunidades estudadas. Os conceitos e as terminologias como segurança alimentar, fome e comida boa foram bem compreendidos, no entanto, comida variada, comida suficiente e estratégia para evitar problemas com comida foram conceitos não compreendidos por eles. A rotina de vida desses povos baseia-se nas relações familiares que permitem trocas, diferindo de outros grupos focais da área urbana e rural, conduzidos como parte da validação da Escala Brasileira de Insegurança Alimentar, nos quais a dificuldade de acesso aos alimentos era conseqüência da falta de recursos financeiros. CONCLUSÃO: São necessários novos e aprofundados estudos, qualitativos e quantitativos, para o desenvolvimento de um instrumento de mensuração de insegurança alimentar que reflita a realidade desses povos, ao mesmo tempo em que busquem fornecer resultados comparáveis com aqueles de outros povos indígenas e mesmo os obtidos pela Escala Brasileira de Insegurança Alimentar em outras populações. Será necessário um instrumento que contemple a questão da troca, o aspecto coletivo, a importância e o uso do ambiente nas experiências de segurança ou insegurança...

OBJECTIVE: The objective was to evaluate the perception and comprehension of concepts and terminology related to food security and insecurity, especially those that comprise the Brazilian Food Insecurity Scale, in the context of indigenous socio-cultural reality. METHODS: Qualitative research techniques were used in Cacau, Flexeira and Mamori indigenous communities located in the Médio Juruá watershed, in the municipalities of Envira and Eirunepé (AM). The methods were based on a methodology used previously in Brazil and adapted to the present context in a meeting of specialists familiar with these indigenous communities. Next, focus groups were organized in each one of the three communities, with a total of 18 participants. RESULTS: Hunger appeared as a phenomenon experienced frequently by the participants. Many of the concepts and terms, such as "food security", "hunger", and "good food", were well-understood, but others, such as "varied food", "sufficient food" "strategies to avoid problems with food" were not. Everyday life depends on family relations that allow exchanges, which differs from studies conducted previously in urban and rural areas, where difficulties related to access to food were due to lack of financial resources. The subject of trading, or exchanges, appeared often during the focus groups, as well as a collective aspect of the experience of food security that had not emerged previously in focus groups conducted as part of the Brazilian Food Insecurity Scale validation. CONCLUSION: More in-depth qualitative and quantitative studies are needed to develop a food security measurement instrument that reflects the reality of these indigenous communities while, at the same time, provides results that are comparable to other indigenous communities as well as to results obtained using the Brazilian Food Insecurity Scale in other populations. To apprehend the situation of food security in these grups is necessary an instrument...

Iridoid glucoside and antifungal phenolic compounds from Spathodea campanulata roots / Iridóide glicosilado e derivados fenólicos antifúngicos isoladosdas raízes de Spathodea campanulata

The chemical study of Spathodea campanulata (Bignoniaceae) roots peels afforded an iridoid glucoside(ajugol) and two phenolic derivatives (p-hydroxy-benzoic acid and methyl p-hydroxy-benzoate). Thecompounds were characterized upon spectral data interpretation. Bioactivities of the constituents wereevaluated against fungus Cladosporium herbarum.

O estudo químico das cascas das raízes de Spathodea campanulata (Bignoniaceae) conduziu ao isolamentode um irióide glicosilado (ajugol) e dois derivados fenólicos (ácido p-hidroxi-benzóico e p-hidroxi-benzoato demetila). Os compostos foram identificados com base na interpretação dos seus dados espectrais. A atividadebiológica destes constituintes foi avaliada contra o fungo Cladosporium herbarum

Antifungal activity of essential oil isolated from Ocimum gratissimum L. (eugenol chemotype) against phytopathogenic fungi

An investigation of antifungal activity of the essential oil obtained by steam-distillation (1.1 percent w/w) of the aerial parts of Ocimum gratissimum and of an ethanolic extract from the steam-distillation residue was carried out using the agar diffusion method. The results revealed that the essential oil inhibited the growth of all fungi tested, including the phytopathogens, Botryosphaeria rhodina, Rhizoctonia sp. and two strains of Alternaria sp., while the extract from the residue was inactive. The essential oil was subjected to TLC bioautography used to detect fungitoxic constituents. The compound that showed antifungal activity was isolated and identified as eugenol. GC/MS analysis showed that eugenol was the main constituent of the essential oil studied. The antifungal activity of eugenol was evaluated against a species of Alternaria isolated from tomato (A1) and Penicillium chrysogenum. The minimal inhibitory concentrations of eugenol were 0.16 and 0.31 mg/disc for Alternaria sp. (A1) and P. chrysogenum, respectively.

O óleo essencial resultante da destilação por arraste a vapor das partes aéreas de Ocimum gratissimum e o extrato etanólico obtido do resíduo da destilação foram avaliados quanto à atividade antifúngica, utilizando-se o método de difusão em agar. O óleo essencial inibiu o crescimento de todos os fungos testados, incluindo os fitopatogênicos Botryosphaeria rhodina e duas espécies de Alternaria sp, enquanto que o extrato do resíduo da destilação não apresentou atividade. O óleo essencial foi, então, submetido ao método de bioautografia em TLC para detecção do composto ativo. O componente ativo foi isolado e identificado através da análise por cromatografia gasosa acoplada à espectrometria de massas como o eugenol, constituinte majoritário do óleo estudado. Ensaios de atividade antifúngica revelaram a atividade do eugenol contra Alternaria isolada de tomate (A1) e Penicillium chrysogenum. As concentrações inibitórias mínimas foram 0,16 mg/disco e 0,31 mg/disco para Arternaria sp (A1) e P. chrysogenum, respectivamente.

Antibacterial activity of Lentinula edodes grown in liquid medium

The antibacterial activity of 35 isolates of Lentinula edodes, a shiitake mushroom, against Bacillus subtilis was evaluated by diffusion technique in agar with a semi-solid overlay. All isolates inhibited B. subtilis and the isolate Le1 promoted the formation of the largest inhibition zone. L. edodes Le1 also presented antibacterial activity against foodborne pathogens and food contaminant bacteria, particularly Gram-positive species. The antibacterial activity of the culture filtrate after 18-25 days of cultivation of L. edodes in broth at 25§C was high. The inhibitory activity was observed only in the organic layer when the culture filtrate was partitioned between ethyl acetate and water, suggesting that the inhibitory substances have low polarity. The silica gel thin-layer zone at Rf values of 0.63-0.80, developed in chloroform - acetone - ethyl acetate - methanol = 40:5:5:2, was responsible for the antibacterial activity against B. subtilis. The inhibitory activity of L. edodes was detectable in the culture filtrate after heat treatment at 100§C for 10 min and after storage at 4§C for 120 days.