Influence of Lentinus edodes and Agaricus blazei extracts on the prevention of oxidation and retention of tocopherols in soybean oil in an accelerated storage test

This study aimed to evaluate the influence of the methanol extracts of mushrooms Lentinus edodes and Agaricus blazei on the retention of tocopherols in soybean oil, when subjected to an accelerated storage test. The following treatments were subjected to an accelerated storage test in an oven at 60 A degrees C for 15 days: Control (soybean oil without antioxidants), TBHQ (soybean oil + 100 mg/kg of TBHQ), BHT (soybean oil + 100 mg/kg of BHT), L. edodes (soybean oil + 3,500 mg/kg of L. edodes extract) and A. blazei (soybean oil + 3,500 mg/kg of A. blazei extract). The samples were analyzed for tocopherols naturally present in soybean oil and mass gain. The results showed, the time required to reach a 0.5% increase in mass was 13 days for TBHQ and 15 days for A. blazei. The content of tocopherols for TBHQ was 457.50 mg/kg and the A. blazei, 477.20 mg/kg.

Avaliação dos efeitos do cogumelo do sol (Agaricus blazei) sobre o colesterol plasmático em coelhos com hipercolesterolemia induzida

Prophylactic or therapeutic treatments administered with medicinal plants and natural products are used in popular medicine of diverse people since prehistoric times to the present days. Species with medicinal properties are increasingly studied in an attempt to understand their possible effects on organisms and their functioning. This study aimed to analyze the effect of the mushroom Agaricus blazei (aqueous extract) in rabbits subjected to experimental hypercholesterolemia. The animals were divided into two groups (control and treated with the mushroom) whose experimental protocol was divided into three phases: Phase 1, the animals were fed a normal diet to evaluate the physiological level of cholesterol; phase 2, the animals were fed a supplemented diet to induce hypercholesterolemia and in phase 3, the animals of control group continued to take high-cholesterol diet and the animals of treated group high-cholesterol diet including treatment with the mushroom. Weekly, after fasting of 14 hours, blood samples were collected from the animals and its plasma was stored for later measurement of plasmatic cholesterol. In the first phase, the cholesterol level was, on average, 31,30  7,34 mgdL-1. In the second phase, there was a significant increase (p<0,05) in cholesterol level of both groups. During the last phase of the experiment, the mushrooms didn’t cause reduction in plasmatic cholesterol of treated rabbits, however, prevent disease progression, maintaining the cholesterol level established at the beginning of treatment, whereas, in the control group, total serum cholesterol increased significantly at this stage

Avaliação dos efeitos renais do extrato aquoso de Agaricus blazei Murrill em ratos Wistar in vivo

O Agaricus balzei Murrill (ABM), comumente conhecido como cogumelo-do-sol, tornou-se popular, devido sua utilização no tratamento de diversas doenças, uma vez que a populaçao em geral lhe atribui diversos efeitos benéficos. Sendo assim, o cogumelo em questão é bastante estudado pelos pesquisadores, na tentativa de validar esses possíveis efeitos medicinais. O presente trabalho pretendeu avaliar os efeitos renais e adicionalmente os parâmetros cardiovasculares, analisando os efeitos do extrato aquoso de ABM em ratos Wistar in vivo. Estes estudos foram realizados em gaiolas metabólicas e os animais divididos em dois grupos: controle (n=8), onde os ratos recebiam uma picada para simular a injeção e experimental (n=10),onde os ratos recebiam 1mL de extrato aquoso à 2% por via intraperitoneal, ao longo do período tratado. Foram avaliados: o fluxo urinário de 24h, carga excretada de sódio (Qe Na+) e carga excretada de potássio (Qe K+) durante o período basal (30dias) e o período tratado (60 dias). Já os parâmetros cardiovasculares foram mensurados (com o sistema BIOPAC), ao fim do período de 60dias de tratamento. Por meio destas análises foi possível registrar uma queda aguda de pressão arterial nos ratos do grupo experimental, durante 15min, nesses ratos. Também foram observadas as respostas barorreflexas e a resposta bradicárdia foi menos acentuadas no grupo experimetal após a administração de fenilefrina (5μg/kg) em comparação ao grupo controle (p<0,05). Os resultados de fluxo urinário de 24h, Qe Na+ e Qe K+ demostraram que o extrato aquoso de ABM foi capaz de promover um aumento significativo (p<0,05) de 36%, 20% e 22%, respectivamente. Os resultados aqui apresentados, indicam que esse extrato tem princípios ativos natriuréticos e, além disso, o extrato apresentou uma redução acentuada após 15min da injeção... (Resumo completo, clicar acesso eletrônico abaixo)

Chemical, enzymatic and cellular antioxidant activity studies of Agaricus blazei Murrill

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Efeito de fungos contaminantes na produtividade de dois isolados de Agaricus blazei em duas formulações de composto

The effect of the contaminant fungi Trichoderma sp. and Chaetomium olivacearum on the cultivation of the ABL 99/30 and ABL 04/49 isolates of A. blazei in two compost formulations made up with tyfton (Cynodom dactylon) and oat (Avena sativa) was evaluated. The experimental design was a totally randomized 2 x 2 x 3 factorial design with 6 repetitions. The experimental unit consisted of 12-12.5 kg of wet compost. During the spawning, 150 g of Trichoderma sp. and C. olivacearum were added to the compost. The experiment was carried out in a climatized room, with humidity between 75-90% and temperature of 28º C. The productivity averages of the ABL 99/30 isolate of A. blazei were higher than those of ABL 04/49 and Trichoderma sp. and C. olivacearum negatively influenced the production of A. blazei. The different composts (based on tyfton and oat straw) did not influence the production of basidiomata.

Use of spent compost in the cultivation of Agaricus blazei

Two compost formulations, based on Braquiaria straw (Brachiaria sp.), a conventional one and a spent one, were tested in the cultivation of ABL 99/30 and ABL 04/49 strains of Agaricus blazei. The experimental design was in a completely randomized factorial scheme with four treatments (two strains of A. blazei x two types of compost) and 30 repetitions. Each experimental unit consisted of a box with 10 to 10.5 kg of moist fresh compost. According to the results obtained, the loss of organic matter of the composts was affected by the A. blazei strain and the type of compost used. The traditional compost lost a higher organic matter content compared to the spent compost, and the ABL 99/30 strain caused a higher loss of organic matter in the composts compared to the ABL 04/49 strain. Yield, biological efficiency, mass and number of basidiomata produced were similar between the conventional and the spent compost, as well as the chemical analysis of the produced basidiomata. However, the A. blazei strains showed some differences among each other, the basidiomata of strain ABL 04/49 obtained a higher percentage of crude protein in their composition, compared to the ABL 99/30, in both composts. Thus, the utilization of spent compost in the cultivation of A. blazei did not impair the basidiomata yield nor their nutritional value, demonstrating it to be a good option to be used as an ingredient in the compost formulation for the A. blazei cultivation.

Avaliação in vitro do crescimento micelial de cinco linhagens de Agaricus blazei em duas temperaturas

The objective of the work was to evaluate the in vitro mycelial growth of five A. blazei strains (ABL-05/53, ABL-04/49, ABL-03/44, ABL-99/30 and ABL-02/51) when submitted to the temperatures of 20 and 25 ºC. In a laminar flow chamber, discs of the strains were inoculated in the middle of Petri’s plates containing CA (compost-agar) medium and incubated in BOD. After 48 hours, measurements of the mycelial growth began, with the help of a ruler with scale in millimeters, by means of four equidistant measurements, until the moment when the fungal colony reached near the edges of the Petri’s plate in one of the treatments. The experimental design was totally randomized, in 5 x 2 factorial design. Each treatment consisted of seven repetitions, corresponding to one Petri’s plate, totalizing seventy experimental units. We verified that A. blazei growth is influenced by incubation temperature, being that the temperature of 25 ºC was more favorable for the mycelial growth of all A. blazei strains tested, with attention for ABL-04/49 and ABL-03/44 strains, which obtained the highest averages for mycelial growth under this temperature condition at the end of the cultivation cycle.

Einige Bemerkungen über den Agaricus salignus Pers.

Von Dr. 0. W. F. Wenderoth

Water-, pH- and temperature relations of germination for the extreme xerophiles Xeromyces bisporus (FRR 0025), Aspergillus penicillioides (JH06THJ), and Eurtotium halophilicum (FRR 2471)

Water activity, temperature and pH are determinants for biotic activity of cellular systems, biosphere function and, indeed, for all life processes. This study was carried out at high concentrations of glycerol, which concurrently reduces water activity and acts as a stress protectant, to characterize the biophysical capabilities of the most extremely xerophilic organisms known. These were the fungal xerophiles: Xeromyces bisporus (FRR 0025), Aspergillus penicillioides (JH06THJ) and Eurotium halophilicum (FRR 2471). High-glycerol spores were produced and germination was determined using 38 media in the 0.995–0.637 water activity range, 33 media in the 2.80–9.80 pH range and 10 incubation temperatures, from 2 to 50°C. Water activity was modified by supplementing media with glycerol+sucrose, glycerol+NaCl and glycerol+NaCl+sucrose which are known to be biologically permissive for X. bisporus, A. penicillioides and E. halophilicum respectively. The windows and rates for spore germination were quantified for water activity, pH and temperature; symmetry/asymmetry of the germination profiles were then determined in relation to supra- and sub-optimal conditions; and pH- and temperature optima for extreme xerophilicity were quantified. The windows for spore germination were ~1 to 0.637 water activity, pH 2.80–9.80 and > 10 and < 44°C, depending on strain. Germination profiles in relation to water activity and temperature were asymmetrical because conditions known to entropically disorder cellular macromolecules, i.e. supra-optimal water activity and high temperatures, were severely inhibitory. Implications of these processes were considered in relation to the in-situ ecology of extreme conditions and environments; the study also raises a number of unanswered questions which suggest the need for new lines of experimentation.

Lipid profile and glycemic response of rats fed on a semi-purified diet supplemented with Agaricus brasiliensis mushroom.

A busca por hábitos alimentares saudáveis tem incentivado o estudo de novas fontes alimentares. Destacam-se os cogumelos comestíveis, como os do gênero Agaricus. Este trabalho avaliou a influência da ração semi-purificada, suplementada com o cogumelo Agaricus brasiliensis no perfil de lipídios, em ratos. Foi realizado experimento com 28 ratos machos Wistar, em 32 dias. Os animais foram separados em quatro grupos de sete dos quais o primeiro recebeu dieta AIN-93 (CAS), o segundo recebeu dieta AIN-93 adicionada de 1% de colesterol (CAS + COL) e o terceiro e o quarto grupos foram alimentados com dieta AIN-93 suplementada com cogumelos sem (COG) e com (COG + COL) adição de colesterol a 1%, respectivamente. No 32.º dia, amostras foram coletadas para análises de colesterol, triglicerídeos, colesterol hepático da gordura hepática. O estudo mostrou que Agaricus brasiliensis influenciou o perfil lipídico, diminuindo o colesterol total (-16%) e os triglicérides (- 26,9%), além de aumentar o HDL (+ 60,2%). É possível afirmar que nutrientes contidos em Agaricus brasiliensis são moduladores do perfil lipídico de ratos, diminuindo a deposição de lipídios hepáticos e aumentando a sua eliminação fecal. A curva glicêmica mostrou declínio significativo entre quinze e sessenta minutos em ratos alimentados com dieta contendo o cogumelo.

Multiplication of microbes below 0.690 water activity: implications for terrestrial and extraterrestrial life

Since a key requirement of known life forms is available water (water activity; aw), recent searches for signatures of past life in terrestrial and extraterrestrial environments have targeted places known to have contained significant quantities of biologically available water. However, early life on Earth inhabited high-salt environments, suggesting an ability to withstand low water-activity. The lower limit of water activity that enables cell division appears to be ∼ 0.605 which, until now, was only known to be exhibited by a single eukaryote, the sugar-tolerant, fungal xerophile Xeromyces bisporus. The first forms of life on Earth were, though, prokaryotic. Recent evidence now indicates that some halophilic Archaea and Bacteria have water-activity limits more or less equal to those of X. bisporus. We discuss water activity in relation to the limits of Earth's present-day biosphere; the possibility of microbial multiplication by utilizing water from thin, aqueous films or non-liquid sources; whether prokaryotes were the first organisms able to multiply close to the 0.605-aw limit; and whether extraterrestrial aqueous milieux of ≥ 0.605 aw can resemble fertile microbial habitats found on Earth.

Is there a common water-activity limit for the three domains of life?

Archaea and Bacteria constitute a majority of life systems on Earth but have long been considered inferior to Eukarya in terms of solute tolerance. Whereas the most halophilic prokaryotes are known for an ability to multiply at saturated NaCl (water activity (a_w) 0.755) some xerophilic fungi can germinate, usually at high-sugar concentrations, at values as low as 0.650–0.605 a_w. Here, we present evidence that halophilic prokayotes can grow down to water activities of <0.755 for Halanaerobium lacusrosei (0.748), Halobacterium strain 004.1 (0.728), Halobacterium sp. NRC-1 and Halococcus morrhuae (0.717), Haloquadratum walsbyi (0.709), Halococcus salifodinae (0.693), Halobacterium noricense (0.687), Natrinema pallidum (0.681) and haloarchaeal strains GN-2 and GN-5 (0.635 a_w). Furthermore, extrapolation of growth curves (prone to giving conservative estimates) indicated theoretical minima down to 0.611 a_w for extreme, obligately halophilic Archaea and Bacteria. These were compared with minima for the most solute-tolerant Bacteria in high-sugar (or other non-saline) media (Mycobacterium spp., Tetragenococcus halophilus, Saccharibacter floricola, Staphylococcus aureus and so on) and eukaryotic microbes in saline (Wallemia spp., Basipetospora halophila, Dunaliella spp. and so on) and high-sugar substrates (for example, Xeromyces bisporus, Zygosaccharomyces rouxii, Aspergillus and Eurotium spp.). We also manipulated the balance of chaotropic and kosmotropic stressors for the extreme, xerophilic fungi Aspergillus penicilloides and X. bisporus and, via this approach, their established water-activity limits for mycelial growth (~0.65) were reduced to 0.640. Furthermore, extrapolations indicated theoretical limits of 0.632 and 0.636 a_w for A. penicilloides and X. bisporus, respectively. Collectively, these findings suggest that there is a common water-activity limit that is determined by physicochemical constraints for the three domains of life.

Biological control of Bradysia matogrossensis (Diptera : Sciaridae) in mushroom cultivation with predatory mites

Larvae of Sciaridae flies (Diptera) cause considerable damage to the mushroom Agaricus blazei (Murrill) ss. Heinemann in Brazil. Brazilian growers have had considerable difficulties in controlling this pest. The objective of this work was to test the effect of the predatory Laelapidae mite Stratiolaelaps scimitus (Womersley) as a control agent of Bradysia matogrossensis (Lane) in cultures of A. blazei. The work corresponded to an evaluation of the efficiency of that predator when released in boxes containing each about 15 L of commercial mushroom compost naturally infested with the pest. The results showed a significant effect of that predator on the population of B. matogrossensis. The release of either 665 or 1330 S. scimitus per box significantly reduced the pest population to levels that, according to grower's experience, apparently could not cause considerable damage. The positive results obtained warrant the conduction of complementary studies to determine the lowest rates of the predator that could still produce acceptable levels of control.

Isolation and mycelial growth of Diehliomyces microsporus: effect of culture medium and incubation temperature

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)