Production of Lignocellulolytic Enzymes and Biomass of Trametes versicolor from Agro-Industrial Residues in a Novel Fixed-Bed Bioreactor with Natural Convection and Forced Aeration at Pilot Scale

Solid-state fermentation requires the development of more efficient cultivation systems for its industrial application. The objective of this work was to evaluate the effect of aeration regime on the production of biomass and several lignocellulolytic enzymes (laccase, manganese peroxidase, endoxylanase, β-glucosidase, and total cellulases) by Trametes versicolor in a novel fixed-bed solid-state pilot-scale bioreactor. Three regimes were assessed: natural convection, low aeration level (10 min every 6 h at 10 L/h air flowrate), and high aeration level (1 h every 6 h at 10 L/h air flowrate). The mushroom was grown on a medium based on lignocellulosic residues. The design of the bioreactor, as well as the control of aeration, humidity, and temperature of the beds, allowed T. versicolor to grow properly on the medium, reaching a maximum biomass production of 204.7 mg/g dry solid (ds). The influence that aeration regime had on the production of lignocellulolytic enzymes was determined. Low level of forced aeration favored obtaining the highest titers of laccase (6.37 U/g ds) compared to natural convection and high aeration level. The greatest lignin degradation was also verified for low aeration regime. For the first time, pilot scale cultivation of T. versicolor was reported in a fixed-bed bioreactor.

Biodegradation of Anthracene Compound by Two Species of Filamentous Fungi

Isolation and identification fungi of Emericella nidulans and Aspergillus flavus from a pinkish and yellowish artificial clay, by using potato dextrose agar (PDA). Results revealed that E. nidulans was the best for degrading anthracene (92.3%) with maximum biomass production (3.7gm/l), compared to A. flavus with the rate of degradation (89%) and biomass production of (1.2gm/l), when methylene blue was used as redox indicator after incubating in a shaker incubator 120rpm at 30Co for 8days. Results indicated that E. nidulans has a high ability of anthracene degradation with the rate of (84%), while A. flavus showed the lower level with (77%) by using HPLC.

Pengaruh Ketebalan Media Budidaya Cacing Sutra (Tubifex sp.) Menggunakan Lumpur Limbah Budidaya Lele

This research aims to know the influence of the thickness of catfish culture waste on silk worm (Tubifex sp.) biomass. The research was conducted with culturing Tubifex sp. in different thickness media of the waste as treatments. The treatments consist of the waste 2, 4, 8 and 12 cm thickness of medium with 6 cm depth. The stock densities 150 g/m3 with average weight 0.0062+0.00032 g. The parameter that analyzed is biomass and population of Tubifex sp.. Data analyzed by analysis of variance and posthoc test is Duncan’s Multiple Range Test. The result shows that diversification of medium thickness gives the real influence (P<0.05) to Tubifex sp. biomass. The highest biomass 1745.14±143.77 g/m3 and population 233,848.46±19265.61 ind./m3 on the treatment with 8 cm thickness. The relationship between treatment and biomass production of Tubifex sp. is quadratic relationship with y = -30.405x2 + 552.18x – 823.55. The optimum thickness of medium that results maximum biomass production is 9.1 cm.

Eficiencia del uso del fósforo en diez genotipos de frijol común (Phaseolus vulgaris L.)

Ten common bean genotypes (Jamapa, APN18, Carioca, Río Tibají, Porrillo, Pot 51, Bat 271, Bolita 42, Calima y CC25-9N) were grown in an intensively aereated nutritive solution with 5 weekly doses of phosphorus (0; 62,5; 125; 187,5 and 1875 mM/plant) and 2 mM of N in the form of KNO3. The objective was to evaluatefoliar biomass and its P content, as well as, to calculate the P Use Efficiency (PUE) parameter based on these and relate them with the concentration levels with which plants were nourished. The optimum requirement level obtained fromboth biomass and PUE criteria ranged between 62,5 - 187,5 mM/plant/week; this supported differences for P nutrition within the genera. Pot 51 showed the lowest requirement and Carioca the highest for optimum yielding; but Bat 271 exhibited the highest efficiency index even at a suboptimum level. Among these genotypes, CC25-9N showed the lowest efficiency and Porrillo showed no variation for this parameter. It may be concluded that the highest efficiency point coincided in 80 % of the cases with the maximum biomass production point.

Utilization of Dairy Wastewater for Pollutants Removal and High Lipid Biomass Production by a Newly Isolated Microalgal Strains Chloromonas playfairii and Desmodesmus opoliensis

Two new unicellular microalgal species from milk processing unit situated at Anand, India were screened and tested for their growth rate and nutrient removal capability under dairy wastewater at outdoor conditions in a simple column aeration photobioreactor. Results of 18s rRNA sequence analysis indicated that these strains have a close relationship with Chloromonas playfairii and Desmodesmus opoliensis named as SBC 2 and SBC 3, respectively. Both the strains removed more than 92% of ammonical nitrogen and 99% of total phosphorus, whereas COD and BOD reductions were found to be more than 95%. Maximum biomass production was 1.7 and 1.2 g L-1 and lipid content was 15 and 12%, respectively from SBC 2 and SBC 3 after 15 d cultivation. This study demonstrates the potential of algae based biofuel production by coupling wastewater treatment with microalgae cultivation for high lipid containing biomass production using Chloromonas playfairii and Desmodesmus opoliensis.Int J Appl Sci Biotechnol, Vol 3(4): 699-707

TRANSIENT MODELING AND SIMULATION OF COMPACT PHOTOBIOREACTORS

In this paper, a mathematical model is developed to make possible the simulation of microalgae growth and its dependency on medium temperature and light intensity. The model is utilized to simulate a compact photobioreactor response in time with physicochemical parameters of the microalgae Phaeodactylum tricornutum. The model allows for the prediction of the transient and local evolution of the biomass concentration in the photobioreactor with low computational time. As a result, the model is expected to be a useful tool for simulation, design, and optimization of compact photobioreactors. Numerical solutions of the mathematical model are presented for the visualization of biomass concentration and total production. Several simulations were performed with temperatures ranging from 274 K to 300 K , and the maximum biomass production was achieved with an operating temperature of 294 K.

Biomass Production and Pigment Accumulation in Kale Grown Under Increasing Photoperiods

Consumption of fruit and vegetable crops rich in lutein and β-carotene carotenoids is associated with reduced risk of cancers and aging eye diseases. Kale (Brassica oleracea L. var. acephala D.C.) ranks highest for lutein concentrations and is an excellent source of dietary carotenoids. Kale plants were grown under varied photoperiods to determine changes in the accumulation of fresh and dry biomass, chlorophyll a and b, and lutein and β-carotene carotenoids. The plants were cultured in a controlled environment using nutrient solutions under photoperiod treatments of 6, 12, 16, or 24 hours (continuous). Fresh and dry mass production increased linearly as photoperiod increased, reaching a maximum under the 24-hour photoperiod. Maximum accumulation of lutein, β-carotene, and chlorophyll b occurred under the 24-h photoperiod at 13.5, 10.4, and 58.6 mg/100 g fresh mass, respectively. However, maximum chlorophyll a (235.1 mg/100 g fresh mass) occurred under the 12-hour photoperiod. When β-carotene and lutein were measured on a dry mass basis, the maximum accumulation was shifted to the 16-hour photoperiod. An increase in photoperiod resulted in increased pigment accumulation, but maximum concentrations of pigments were not correlated with maximum biomass production.