Herta Stutz Dalla Santa

Spore production of Beauveria bassiana from agro-industrial residues

The purpose of this work was to produce Beauveria bassiana by Solid-State Fermentation using agro-industrial residues and optimizing the cultivation conditions. Refused potatoes, coffee husks and sugar-cane bagasse were tested. The blend of refused potatoes and sugar-cane bagasse (60-40%) with particle size in the range of 0.8-2 mm was used in the fermentation experiments. In Erlenmeyer flasks the best spore production was achieved with the following conditions: incubation temperature 26o C; initial pH 6.0; inoculum concentration 107 spores.g-1.dw and initial moisture 75%. In the column type reactor using forced aeration under the optimized conditions, the maximum production (1.07x1010spores.g-1.dw) was obtained at the 10th day of fermentation. The respirometric analyses of the fermentation showed a strong correlation between fungal growth and spore production.

Medicinal mushroom Ganoderma lucidum (Leyss: Fr) Karst. triggers immunomodulatory effects and reduces nitric oxide synthesis in mice.

This study investigated the effect of Ganoderma lucidum supplementation on lymphocytes and peritoneal macrophages from mice. Our results show that G. lucidum in vivo was able to increase interferon-gamma (IFN-gamma) concentration but reduced CD3(+) and CD8(+) spleen lymphocytes. Ex vivo, IFN-gamma; and interleukin-10 levels were increased and the tumor necrosis factor-alpha (TNF-alpha) level was reduced by peritoneal macrophages from mice fed with G. lucidum. In the absence of stimuli nitric oxide production was reduced in mice fed with G. lucidum, and with lipopolysaccharide stimulation nitric oxide production was increased but was lower than control values (P < .05). G. lucidum was grown by solid-state culture in wheat grain, and a chow containing 10% G. lucidum mycelium was formulated (G10). Swiss male mice were divided into two groups, termed G10 and control groups according to the diet, and were fed for 3 months. Peritoneal macrophages were obtained and investigated with regard to phagocytosis, lysosomal volume, hydrogen peroxide, superoxide anion, and cytokines ex vivo. In the plasma we investigated concentrations of cytokines, and in the spleen we determined subsets of CD3(+), CD4(+), CD8(+), and CD19(+) lymphocytes.

Use of starter cultures isolated from native microbiota of artisanal sausage in the production of Italian sausage

The most promising microorganisms for use as starter cultures are those isolated from the native microbiota of traditional fermented products. The aim of this study was to evaluate the use of lactic acid bacteria selected from the native microbiota of sausages produced by spontaneous fermentation as starter cultures for the production of sausage. Strains of Lactobacillus plantarum 503 and 341 have the potential for use as starter cultures in the manufacture of Italian sausage type. The population of lactic acid bacteria in sausages was >8 log CFU.g-1 during fermentation, which caused the pH to decrease to <4.5. This decrease in pH and the water activity of < 0.90 of sausages ensures the safety and preservation of this product. Sausages produced with these lactic cultures fulfill the requirements for microbiological quality and composition of Italian sausage type. Our results suggest the possibility of using these starter cultures for the production of sausages with peculiar characteristics that contribute to the identity of the product.

Microbiota of sausages obtained by spontaneous fermentation produced in the South of Brazil

The study of the ecology of fermented sausage is fundamental to understand the physical and chemical changes that happen during fermentation and maturation. The aim of the present study was to determine the microbiological characteristics of sausages produced by spontaneous fermentation. Fifty samples of sausages produced in the South of Brazil by different small manufacturers were analyzed for the following microbiota: aerobic mesophilic bacteria; Micrococcaceae; mold and yeast; lactic acid bacteria; total and fecal coliforms; coagulase-positive Staphylococcus, and Salmonella. In most samples (72%), the count of lactic bacteria was higher than 6 log 10 cfu.g -1 , and the samples with the highest counts were above 8 log 10 cfu.g -1 . The counts of Micrococcaceae in most samples were between 5 log 10 and 7 log 10 cfu.g -1 . With respect to the presence of molds and yeasts, there was a significant variation among the samples with counts ranging from 2 log 10 cfu.g -1 and 6 log 10 cfu.g -1 . From the data obtained, it was possible to conclude that 24% of the analyzed samples did not comply with the current law in Brazil since the levels of fecal coliforms or coagulase-positive Staphylococcus exceeded the maximum limit allowed.

Immunomodulatory and Antitumoral Properties of Ganoderma lucidum and Agaricus brasiliensis (Agaricomycetes) Medicinal Mushrooms

Medicinal mushrooms are used in popular medicine largely as health promoters, mainly because of their antitumor and immunomodulatory activities. Ganoderma lucidum (lingzhi or reishi) and Agaricus brasiliensis are mushrooms that have long been used for medicinal purposes. This study evaluated their immunomodulatory and antitumor effects on mice fed a diet supplemented with G. lucidum and A. brasiliensis mycelia obtained from solid-state fermentation. For 14 weeks the mice were fed chow containing 50% A. brasiliensis and G. lucidum mycelia, using ground wheat as an excipient. The consumption of the supplemented diet inhibited Sarcoma 180 tumor growth and caused important changes in the immune system. The pattern of immune response shifted, increasing CD4+ and CD8+ and decreasing CD19+ cell populations. The restoration of a proper balance between cellular and humoral immunity is an essential process for restraining tumor growth. These results suggest that polysaccharides, such as β-glucans and other mushroom metabolites, possibly promote the T-cell dominance that is imperative to restrain tumor growth.

In Vitro and In Vivo Antitumoral Activity of Exobiopolymers from the Royal Sun Culinary-Medicinal Mushroom Agaricus brasiliensis (Agaricomycetes)

We studied antitumor activity in vitro and in vivo and partial chemical characterization of exobiopolymers (EBPs) of Agaricus brasiliensis produced by submerged cultivation. The EBPs comprised 61.2% total sugar and 22.3% total protein, and the chromatographic profile mainly identified mannose (65.5%), galactose (17.5%), and glucose (13.1%). In vitro analysis revealed a dose with antitumor effectiveness, time-dependent treatment, and 46% inhibition of solid Walker 256 tumors in rats. Metabolic changes were significant in the spleens of the animals; this is possibly related to higher immune activity triggered by the presence of EBPs in the treated group. The increase of nitric oxide production by peritoneal macrophages from animals may be related to the tumor reduction observed, because nitric oxide acts as an important effector pathway in the defense of the organism.

Análise do potencial antioxidante do consumo oral da farinha produzida com micélio de Agaricus brasiliensis em hamsters hipercolesterolêmicos

The main function of antioxidant defense system is to inhibit or reduce the cells damage caused by reactive oxygen species. Some antioxidants occurring in the diet enhance the antioxidant defense of plasma. The antioxidant potential of oral intake of a flour produced with A. brasiliensis mycelium fermented on wheat grains was evaluated in plasma samples from male hypercholesterolemic Syrian Golden hamsters, were divided into four groups: P (standard diet), H (standard hypercholesterolemic diet), C (standard diet + 10 % of wheat flour containing mycelium of A. brasiliensis), and HC (standard diet hypercholesterolemic + 10 % wheat flour containing mycelium of A. brasiliensis). The animals were fed for 40 days and then sacrificed for collecting plasma. The antioxidant capacity analysis showed that the dietary intake of group C induced the most significant increase of antioxidants concentrations in plasmas (0.39 mg.mL-1, expressed in ascorbic acid). The HC group showed higher antioxidant capacity than the H group (p < 0.05), as it inhibited 20.2 % of crocin bleaching, while the H group inhibited 10.4 % only; however the HC group showed a similar antioxidant capacity of P group (16.64 %). It is suggested that the consumption of wheat flour containing mycelium of A. brasiliensis induced the antioxidant protection in animals plasma.