427 research outputs found
Purification of an Exopolygalacturonase from Penicillium viridicatum RFC3 Produced in Submerged Fermentation
An exo-PG obtained
from Penicillium viridicatum in
submerged fermentation was purified to
homogeneity. The apparent molecular weight of
the enzyme was 92 kDa, optimum pH and
temperature for activity were pH 5 and
50–55°C. The exo-PG showed a profile of an
exo-polygalacturonase, releasing galacturonic acid by hydrolysis
of pectin with a high degree of esterification (D.E.). Ions
Ca2+ enhanced the stability of enzyme and its activity by 30%. The Km was 1.30 in absence of Ca2+ and 1.16 mg mL−1 in presence of this ion. In relation to the Vmax the presence of this ion increased from 1.76 to 2.07 μmol min−1mg−1
Agaricus blazei, supstrat za proizvodnju β-1,3-glukanaze s pomoću Trichoderma harzianum Rifai
Extracellular β-1,3-glucanase was produced by Trichoderma harzianum Rifai cultivated in the Agaricus blazei (Agaricus brasiliensis) extract as a substrate in submerged fermentation. A 2²-central composite factorial design was developed using the time of culture (x1/day) and Agaricus blazei extract concentration (x2/(g/L)) as variables, and the results were analyzed using response surface methodology (RSM). The results showed that the Agaricus blazei extract concentration was the most important variable in the production of β-1,3-glucanase, and the maximum β-1,3-glucanase activity (0.77 U/mL) was obtained in one day of cultivation. The β-glucan present in the cell wall of Agaricus blazei mushroom proved to be a good substrate for inducing the production of specific β-1,3-glucanase by Trichoderma harzianum Rifai.Ekstrakt gljive Agaricus blazei (Agaricus brasiliensis) upotrijebljen je kao supstrat za proizvodnju β-1,3-glukanaze submerznim uzgojem plijesni Trichoderma harzianum Rifai. Centralno složeni 22 faktorijalni dizajn razvijen je primjenom ovih varijabla: vrijeme uzgoja (x1/dan) i koncentracija ekstrakta Agaricus blazei (x2/(g/L)), a rezultati su analizirani metodom odzivnih površina (RSM). Rezultati pokazuju da je koncentracija ekstrakta Agaricus blazei najvažnija varijabla za proizvodnju β-1,3-glukanaze, a maksimalna je aktivnost enzima od 0,77 U/mL dobivena nakon prvoga dana uzgoja. β-Glukan u staničnoj stijenci gljive Agaricus blazei dobar je supstrat za proizvodnju specifične β-1,3-glukanaze s pomoću Trichoderma harzianum Rifai
Zukunft Haldenlandschaft im Aachener Revier : 10 Haldenentwürfe von Studierenden
Microbial β-glucosidases have been used for the enhancement of wine aroma. Nevertheless, few enzymes are active in the conditions of winemaking. In this work, the production of a β-glucosidase by an Aureobasidium pullulans strain (Ap-β-gl) isolated from grape ecosystems was evaluated. The maximum enzymatic synthesis using submerged fermentation was after 96 h of growth in complex media containing 20 g/L of cellobiose as the sole carbon source. The crude enzyme (Ap-β-gl) showed optimal pH at 5.5 and two peaks of optimum temperature (at 45 and 70 C). It showed a wide range of pH stability, stability at low temperatures, and tolerance to ethanol, showing suitable characteristics for winemaking conditions. The hydrolysis of glycosidic terpenes by Ap-β-gl was studied, and its ability to efficiently release free terpenols was demonstrated by gas chromatography/mass spectrometry. The enzymatic treatment notably increased the amount of monoterpenes, showing good prospects for its potential application for the development of aroma in wines. © 2012 Springer Science+Business Media New York
Chemical composition and antioxidant activity of dried powder formulations of Agaricus blazei and Lentinus edodes
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.Capes-Carolina Foundation (Brazil) for the scholarship of doctoral sandwich (A.A.J. Carneiro), held at the Faculty of Pharmacy, University of Salamanca, Spain in partnership with the Polytechnic Institute of Bragança, Portugal. A.A.J. Carneiro is thankfull to FAPESP and CNPq (Brazil) for financial support and for the scholarship (Brazil). CIMO is grateful to strategic project PEst-OE/AGR/UI0690/2011 for financial support. L. Barros thanks to FCT, POPH-QREN and FSE for her grant (SFRH/BPD/4609/2008). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Dueñas thanks the Spanish “Ramón y Cajal” Programme for a contract
Agaricus blazei and Lentinus edodes dried formulations: chemical composition and antioxidant activity
A balanced diet is one of themainstays ofiherapyfor the prevention of the oxidative stress, which if cannot beeliminated, at leastcan be controlled. Food antioxidants may help
intrinsic antioxidant mechanisms to fight against oxidative stress. Several mushroom species have been pointed out as sources of antioxidant compounds, besides their nimportant nutritional value. Agaricus blazei and Lentimrs 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 analysed
by chromatographic methods) and antioxidant activity (free radical scavenging activity,
reducing power and lipid peroxidation inhibition) of dried powder formulations of Agaricus blazei (APF) and Lentimrs edodes (LPF) from São Paulo, Brazil were evaluated.141
Powder formulations of both species revealed the presence of essential nutrients such as
proteins, carbohydrates and unsaturated limy acids. Furthermore, they present low fat
content (<2 g/100 g) and can be used in low-caloric diets, just like the mushroom fruiting
bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 μg/l 00 g and 770 μg/l 00 g, respectively) than LPF (32 μg/ l 00 g and 690 μg/100 g).Both formulations might be used as antioxidant sources to prevent
diseases related to oxidative stress
Industrial sustainability of microbial keratinases: production and potential applications
ReviewKeratinases are proteolytic enzymes with a particular ability to cleave peptide bonds in keratin, and in other proteins. Due to
their broad-spectrum of activity, keratinases are considered viable substitutes for chemical and thermal treatments of proteinrich
industrial by-products. Among these protein residues, special attention has been given to keratinous materials (feathers,
hair, horns, etc.), which disposal through harsh conditions methods, such as acid/alkaline hydrolysis or incineration, is not
considered ecologically safe. Microbial keratinolytic enzymes allow for keratin degradation under mild conditions, resulting
in keratin hydrolysates containing undamaged amino acids and peptides. In this review article, we offer perspectives
on the relevance of these unique biocatalysts and their revolutionary ascent in industries that generate keratin-rich wastes.
Additionally, we share insights for applications of keratinases and protein hydrolysates in agriculture, animal feed, cosmetics,
phamaceuticals, detergent additives, leather processing, and others. Due to the scientific importance of keratinases and
their potential use in green technologies, searching for bacterial and fungal species that efficiently produce these enzymes
may contribute to the sustainability of industriesinfo:eu-repo/semantics/publishedVersio
Effect of Metal Ions, Chemical Agents and Organic Compounds on Lignocellulolytic Enzymes Activities
Lignocellulolytic enzymes have been extensively studied due to their potential for industrial applications such as food, textile, pharmaceutical, paper, and, more recently, energy. The influence of metal ions, chemical agents, and organic compounds on these enzyme activities are addressed in this chapter, based on data available in the scientific literature
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