Showing papers on "Termitomyces clypeatus published in 2015"

Major, Minor and Toxic Minerals and Anti-Nutrients Composition in Edible Mushrooms Collected from Ethiopia

Abstract: Major (Na, K, Ca, Mg, P), minor (Mn, Cu, Fe, Zn) and toxic (Pb, Cd) minerals composition of twelve edible mushrooms (Pleurotus ostreatus, Lentinula edodes, Agaricus bisporus #1 (fresh), Agaricus bisporus #2 (canned), Agaricus campestris, Laetiporus sulphureus, Termitomyces clypeatus, Termitomyces microcarpus #1, Termitomyces microcarpus #2, Termitomyces aurantiacus, Termitomyces letestui and Termitomyces species) collected from three regions of Ethiopia were analyzed. The samples were further investigated for their antinutrients (phytate and condensed tannin) to determine bioavailability of minerals. All the results are expressed in dry basis (db). The major minerals concentration (mg/g) ranged: Na (0.41-34.8), K (3.66-42.4), Ca (0.29-6.45), Mg (0.57-2.12) and P (0.71-2.82). The minor (mg/kg) ranged: Fe (32.5-6835.9), Zn (26.6-87.6), Cu (5.69-45.9) and Mn (0.96-138.6). The toxic metal lead was detected (1.52-18.0 mg/kg), indicating most of the mushrooms samples exceeded the weekly tolerance limit set for Pb with more proportion in wild than cultivated mushrooms. Cadmium was detected only in A.campestris (4.08 mg/kg). The anti-nutrients (mg/100 g) were significantly varied with phytate ranged from 31.3 to 242.8 and condensed tannin from 4.81 to 31.7. The calculated molar ratio between phytate and Fe, Zn and Ca was above the suggested critical values indicating the bioavailability of Fe, Zn and Ca to be high. In conclusion, the results imply that the edible mushrooms have high concentrations of essential minerals with lower anti-nutrients that make them bioavailable to the human body. Although, the consumption of some contaminated mushrooms should be avoided.

Biomass of Termitomyces clypeatus for chromium(III) removal from chrome tanning wastewater

Abstract: Chrome tanning wastewater generated during leather processing is one of the major source of aquatic contamination which has deleterious effect on the environment. To deal this problem, many types of biosorbents have been used so far. In this study, fugal biomass of Termitomyces clypeatus, a byproduct of enzyme, and fermentation industry have been employed for Cr(III) removal from chrome tanning effluent. The maximum metal uptake (q e) of 24.84 mg g−1 was obtained with an optimum pH and temperature of 4 and 60 °C for an initial metal concentration of 100 ppm at an adsorbent dosage of 2 g L−1. Adsorption process was best fitted by pseudo-second-order kinetic model. Sorption process obeys Freundlich adsorption isotherm model, rather than Langmuir. The presence of functional groups and morphological changes on the biomass responsible for metal uptake was confirmed by FT-IR and scanning electron microscopy–energy dispersive X-ray spectroscopy analyses.

Bioremediation by alkaline protease (AkP) from edible mushroom Termitomyces clypeatus: optimization approach based on statistical design and characterization for diverse applications

Abstract: BACKGROUND Bioremediation using enzymes has become an attractive approach for removing hazardous chemicals from the environment. The present study investigated the production, optimization and applications of an extracellular alkaline protease (AkP) from the edible mushroom Termitomyces clypeatus focusing on bioremediation. RESULTS For optimized enzyme production, the variables significantly influencing the protease activity were screened through the 11 factorial Plackett–Burman design. The optimum values of the selected variables and their mutual interactions were determined through response surface methodology using the Box–Behnken experimental design. Overall a 10-fold increase in enzyme activity (1830 U mL-1) was obtained which closely matched the yield predicted by the statistical model (1778.63 U mL-1) with R2 = 0.9819. AkP could efficiently dehair the goat skin, detached bird feather vanes from its shaft and reduce BOD, COD and pH of tannery waste effluent. The AkP also demonstrated bactericidal property against Staphylococcus aureus as detected by MIC and flow cytometry analyses. CONCLUSION As an ecofriendly alternative, the enzyme showed significant promise for bioremediation and industrial applications through time-saving bioprocesses. This is first report of alkaline protease from T. clypeatus or from a fungal source with wide-ranging application potential. © 2014 Society of Chemical Industry

Enhancement of extracellular cellobiase activity by reducing agents in the filamentous fungus Termitomyces clypeatus

Abstract: Extracellular cellobiase activity of Termitomyces clypeatus increased from 2.9 U ml−1 to 4.4 and 4.1 in presence of dithiothreitol (DTT) and β-mercaptoethanol (ME), respectively, with a decrease in Km from 0.4 to 0.3 mM (DTT) and 0.35 mM (ME). Catalysis was further enhanced if the reduced enzyme was alkylated and activity increased from 11.4 U ml−1 (control) to 15.2 (DTT+N-ethylmaleimide) and 15.3 (DTT+iodoacetamide) using p-nitrophenyl-β-d-glucopyranoside and from 14.6 U ml−1(control) to 21.9 (DTT+N-ethylmaleimide) and 18.7 (DTT+iodoacetamide) using cellobiose. The reduced enzyme showed 17 % lesser glucose inhibition. CD and tryptophan fluorescence showed no change in secondary structure was caused by DTT up to 50 mM. Cysteine content of the enzyme was 24 %. It is postulated that reduction of disulphide bonds allows better substrate affinity for cellobiase. The studies describe a novel and simple method to increase cellobiase activity for industrial applications.