Several mushroom species have been pointed out as sources of antioxidant compounds, besides their important nutritional value. Agaricus blazei and Lentinus edodes are among the most studied species all over the world, but those studies focused on their fruiting bodies instead of other presentations like powdered preparations used as supplements. In the present work the chemical composition (nutrients and bioactive compounds) and antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) of dried powder formulations of the mentioned mushroom species (APF and LPF, respectively) were evaluated.Powder formulations of both species revealed the presence of essential nutrients such as proteins, carbohydrates and unsaturated fatty acids. Furthermore, they present low fat content (<2 g/100 g) and can be used in low-caloric diets, just like the mushrooms fruiting bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 µg/100 g and 770 µg/100 g, respectively) than LPF (32 µg/100 g and 690 µg/100 g). Both formulations might be used as antioxidant sources to prevent diseases related to oxidative stress.

Cyclodextrins (CDs) are cyclic oligasaccharides composed by D-glucose monomers joined by alpha-1,4-D glicosidic linkages. The main types of CDs are alpha-, beta- and gamma-CDs consisting of cycles of six, seven, and eight glucose monomers, respectively. Their ability to form inclusion complexes is the most important characteristic, allowing their wide industrial application. The physical property of the CD-complexed compound can be altered to improve stability, volatility, solubility, or bio-availability. The cyclomaltodextrin glucanotransferase (CGTase, EC 2.4.1.19) is an enzyme capable of converting starch into CD molecules. In this work, the CGTase produced by Bacillus clausii strain E16 was used to produce CD from maltodextrin and different starches (commercial soluble starch, corn, cassava, sweet potato, and waxy corn starches) as substrates. It was observed that the substrate sources influence the kind of CD obtained and that this CGTase displays a beta-CGTase action, presenting a better conversion of soluble starch at 1.0%, of which 80% was converted in CDs. The ratio of total CD produced was 0:0.89:0.11 for alpha/beta/gamma. It was also observed that root and tuber starches were more accessible to CGTase action than seed starch under the studied conditions.

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Three mutations, Ser54→Pro, Thr314→Ala, and His415→Tyr, were identified in Aspergillus awamori glucoamylase gene expressed by Saccharomyces cerevisiae. The mutant glucoamylase (GA) was substantially more thermostable than a wild-type GA at 70 °C, with a 3.0 KJ mol(-1) increase in the free energy of thermo-inactivation. The effect of starch from different botanical sources on the production of this GA was measured in liquid fermentation using commercial soluble starch, cassava, potato, and corn as the carbon source. The best substrate for GA production was the potato starch showing an enzymatic activity of 6.6 U/mL. The commercial soluble starch was also a good substrate for the enzyme production with 6.3 U/mL, followed by cassava starch and corn starch with 5.9 and 3.0 U/mL, respectively. These results showed a significant difference on GA production related to the carbon source employed. The mutant GA was purified by acarbose-Sepharose affinity chromatography; the estimated molecular mass was 100 kDa. The mutant GA exhibited optimum activity at pH 4.5 and an optimum temperature of 65 °C.