straw Dotaz Zobrazit nápovědu
- MeSH
- klasifikace * MeSH
- lidé MeSH
- reprodukční systém - fyziologické jevy * MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
The pretreatment methods for enhancing biogas production from oat straw under study include hot maceration, steam explosion, and pressure shockwaves. The micropore area (9, 55, and 64 m(2) g(-1)) inhibitor formations (0, 15, and 0 mL L(-1)) as well as the overall methane yields (67, 179, and 255 CH4 VS t(-1)) were robustly analyzed. It was confirmed that the operating conditions of the steam explosion must be precisely tailored to the substrate. Furthermore, it was beneficial to prepend the hot maceration before the steam explosion and the pressure shockwaves. The second alternative may give increased methane yields (246 in comparison to 273 CH4 VS t(-1)); however, the application of pressure shockwaves still faces limitations for deployment on a commercial scale.
In this work hydrothermally pretreated wheat straw was used for production of bioethanol by Saccharomyces cerevisiae and carotene-enriched biomass by red yeasts Rhodotorula glutinis, Cystofilobasidium capitatum and Sporobolomyces roseus. To evaluate the convertibility of pretreated wheat straw into ethanol, simultaneous saccharification and fermentation of S. cerevisiae was performed under semi-anaerobic conditions. The highest ethanol production efficiency of 65-66% was obtained following pretreatment at 200°C without the catalytic action of acetic acid, and at 195 and 200°C respectively in the presence of catalyst. Red yeast strain S. roseus produced 1.73-2.22 mg g(-1) of ergosterol on the filter cake, 1.15-4.17 mg g(-1) of ergosterol and 1.23-1.56 mg g(-1) of β-carotene on pretreated wheat straw hydrolysates and also the highest amount of carotenoids and ergosterol on untreated wheat straw (1.70 and 4.17 mg g(-1), respectively).
- MeSH
- biomasa * MeSH
- biopaliva mikrobiologie MeSH
- bioreaktory mikrobiologie MeSH
- biotechnologie metody MeSH
- ergosterol biosyntéza MeSH
- ethanol metabolismus MeSH
- glukosa metabolismus MeSH
- hydrolýza účinky léků MeSH
- karotenoidy metabolismus MeSH
- kvasinky účinky léků růst a vývoj metabolismus MeSH
- odpadní produkty analýza MeSH
- pšenice účinky léků MeSH
- sacharidy chemie MeSH
- teplota * MeSH
- voda farmakologie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
An investigation was carried out using rice straw as a low-cost substrate to study the optimization of xylanase production using a newly identified endospore-forming bacterium, Bacillus altitudinis RS3025. The highest xylanase activity was achieved using 2% rice straw (pretreated with 2% NaOH at 100 °C) at pH 7.0, 37 °C temperature, and with 72-h incubation time. Under the optimized conditions, xylanase activity reached 2518.51 U/mL, which was 11.56-fold higher than the activity under the initial conditions using untreated rice straw as substrate. Enzymatic hydrolysis of the rice straw using crude xylanase of B. altitudinis RS3025 demonstrated the hydrolyzation efficiency of the rice straw waste, especially alkaline rice straw. The highest level of released reducing sugars was 149.78 mg/g substrate. The study demonstrated the successful utilization of rice straw waste for high-level xylanase production using B. altitudinis RS3025 and reducing sugar production using low-cost crude enzyme, which has the advantages of reducing the processing cost and environmental concerns associated with rice straw waste management.
- MeSH
- Bacillus * metabolismus MeSH
- celulasa * MeSH
- fermentace MeSH
- hydrolýza MeSH
- rýže (rod) * metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- Publikační typ
- abstrakt z konference MeSH
- MeSH
- celulosa metabolismus MeSH
- herbicidy MeSH
- houby fyziologie účinky léků MeSH
- pšenice mikrobiologie MeSH
- půdní mikrobiologie MeSH
- Publikační typ
- srovnávací studie MeSH
Dating of clay bricks (adobe) and plasters is a relevant topic not only for building historians in the Pannonian region. Especially in vernacular architecture in this region, clay with straw amendments is a dominant construction material. The paper presents the potential of the molecular decay of these amendments to establish prediction tools for age based on infrared spectroscopic measurements. Preliminary results revealed spectral differences between the different plant parts, especially culms, nodes, and ear spindles. Based on these results, a first prediction model is presented including 14 historic samples. The coefficient of determination for the validation reached 62.2%, the (RMSE) root mean squared error amounted to 93 years. Taking the limited sample amount and the high material heterogeneity into account, this result can be seen as a promising output. Accordingly, sample size should be increased to a minimum of 100 objects and separate models for the different plant parts should be established.
- MeSH
- časové faktory MeSH
- jíl chemie MeSH
- konstrukční materiály analýza MeSH
- spektrální analýza MeSH
- stopové prvky analýza MeSH
- Publikační typ
- časopisecké články MeSH
The present study was set to develop a robust and economic biorefinery process for continuous co-production of ethanol and xylitol from rice straw in a membrane bioreactor. Acid pretreatment, enzymatic hydrolysis, detoxification, yeast strains selection, single and co-culture batch fermentation, and finally continuous co-fermentation were optimized. The combination of diluted acid pretreatment (3.5 %) and enzymatic conversion (1:10 enzyme (63 floating-point unit (FPU)/mL)/biomass ratio) resulted in the maximum sugar yield (81 % conversion). By concentrating the hydrolysates, sugars level increased by threefold while that of furfural reduced by 50 % (0.56 to 0.28 g/L). Combined application of active carbon and resin led to complete removal of furfural, hydroxyl methyl furfural, and acetic acid. The strains Saccharomyces cerevisiae NCIM 3090 with 66.4 g/L ethanol production and Candida tropicalis NCIM 3119 with 9.9 g/L xylitol production were selected. The maximum concentrations of ethanol and xylitol in the single cultures were recorded at 31.5 g/L (0.42 g/g yield) and 26.5 g/L (0.58 g/g yield), respectively. In the batch co-culture system, the ethanol and xylitol productions were 33.4 g/L (0.44 g/g yield) and 25.1 g/L (0.55 g/g yield), respectively. The maximum ethanol and xylitol volumetric productivity values in the batch co-culture system were 65 and 58 % after 25 and 60 h, but were improved in the continuous co-culture mode and reached 80 % (55 g/L) and 68 % (31 g/L) at the dilution rate of 0.03 L per hour, respectively. Hence, the continuous co-production strategy developed in this study could be recommended for producing value-added products from this hugely generated lignocellulosic waste.
- MeSH
- biomasa MeSH
- bioreaktory * MeSH
- biotransformace MeSH
- celulosa metabolismus MeSH
- dusík metabolismus MeSH
- ethanol metabolismus MeSH
- fermentace * MeSH
- hydrolýza MeSH
- kinetika MeSH
- kyseliny sírové metabolismus MeSH
- kyslík metabolismus MeSH
- rýže (rod) metabolismus mikrobiologie MeSH
- Saccharomyces cerevisiae metabolismus MeSH
- xylitol metabolismus MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
