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The first objective of this study was the measurement of physical properties of P(3HB-co-3HV) copolymers with different (hydroxybutyrate) HB to (hydroxyvalerate) HV ratios produced by (TRY2) isolated from activated sludge. The 3HV PHBV copolymers were 0.05, 22.6, 39.2, 54.1, and 69.1 mol%, respectively. The second objective was to study possible waste-water treatment and production of PHAs at the same time by (TRY2) and spp. (TOB17) (both were isolated from activated sludge), recombinant , and a combination of the above three bacteria. The results were satisfactory; the maximum COD and TOC of the sewage sludge reduced were 53.5% and 67.5%, respectively.

The dilute-acid hydrolysis of sugarcane bagasse was optimized using a statistical experimental design resulting in hydrolysates containing 57.25 g/L of xylose, which were fermented with a high inoculum concentration (10 g/L of the yeast IM/UFRJ 50088). The addition of urea reduced the time of conversion (C) to 75 h (without nitrogen source addition > 127 h), and, consequently, improving the rates of xylitol bioproduction. Fermentator experiments, using the optimized conditions, resulted in enhanced conversion rates, reducing to 30 h. The stability of the yeast in the hydrolysate was also verified in a 480-h cultivation.

The effects of the addition of lysozyme and forced aeration on the rheological properties and production of hyaluronic acid by were investigated. Lysozyme was added to the culture broth in two pulses during the exponential and stationary phases of a fermentation carried out in a rotary shaker (150 rpm), using 200 mL Erlenmeyer flasks. The effect of aeration was evaluated by feeding air into a 2.5 L fer-mentor at a 2 vvm rate. The effects were analyzed in terms of concentration, viscosity, viscoelasticity, and molecular weight of the hyaluronic acid produced.

The biorefinery is a key concept used in the strategies and visions of many industrial countries. The potential for Canadian biorefineries based on lingo-cellulosic forest and agricultural residues is examined. The sector is described in terms of research interests, emerging companies, and established corporate interests. It is found that the Canadian biorefining sector currently has an emphasis on specific bioproduct generation, and the process elements required for a true sugar-based process are in the research phase. A Canadian national strategy should focus on increasing forest industry participation, and increasing collaboration with the provinces, particularly in western Canada.

The production of chemicals from lignocellulosics continues to be an active area of research. Improved economics for lignocellulosic-based chemical production processes can be realized through the integration of these processes into existing bioprocessing facilities that are often described as biorefineries. The focus of some of the most recent work in this area is the topic of session 5. Research described by the speakers in this session illustrates the capturing of additional value from low value coproducts and alternative products from several industries. Examples from the talks include the production of fuels such as ethanol and biodiesel from industrial processing co-products; increased value from feed fibers as provided in the talk on the corn processing industry; multiple products and co-products from woody biomass and sugarcane fiber lignins; and syngas from glycerol obtained as a byproduct from vegetable oil processing to biodiesel. While many of the presentations provided an overview of the employment of separation technologies to biomass feedstocks, one presentation directly highlighted the impediments to the production of polyols by chemical catalysis of lignocellulosic feedstocks. Since a similar problem exists in microbial biocatalyst inhibition by lignocellulosic hydrolysates, the development of innovative pretreatment, hydrolysis and separation technologies to overcome microbial inhibition and catalyst poisoning will be essential for progress in this area.

Kudzu () foliage has been touted as a possible energy crop. High-performance liquid chromatography and mass spectrometry analysis of the methanolic kudzu foliage extracts confirmed the presence of robinin (kaempferol-3--robinoside-7--rhamnoside). Robinin accounted for 0.65 ± 0.16% (dry basis) of kudzu biomass. Fast performance liquid chromatography (FPLC) was employed to fractionate robinin from the crude extract. The antioxidant capacity of robinin was evaluated by an oxygen radical absorbance capacity (ORAC) assay. The ORAC values of pure standard were compared with those of the extract fractions. One milligram of the FPLC-fractionated robinin generated an ORAC value of 5.15 ± 2.00 umol/mg of Trolox, whereas 1 mg of pure robinin generated an ORAC value of 12.34 ± 0.45 µmol/mg of Trolox. Because of its antioxidant properties, robinin may be a flavonoid worth extracting prior to energy production.

Japanese beech ( Blume), its cell wall components, and model compounds were treated by supercritical water (380°C, 100 MPa) for 5 s using a batch-type reactor to investigate the production behavior of low molecular weight organic acids. It was found that cellulose and hemicellulose were decomposed to formic acid, pyruvic acid, glycolic acid, acetic acid, and lactic acid, whereas lignin was barely decomposed to such organic acids under the given conditions. However, after prolonged treatment (380°C, 100 MPa, 4 min) of lignin, some organic acids were recovered owing perhaps to the decomposition of the propyl side chain of lignin. It was additionally revealed that the predominant organic acid recovered was acetic acid, which might be derived from the acetyl group of hemicellulose in Japanese beech.

In recent years, the concept of producing biodiesel from renewable lipid sources has regained international attention. In Brazil, a national program was launched in 2002 to evaluate the technical, economic, and environmental competitiveness of biodiesel in relation to the commercially available diesel oil. Several research projects were initiated nationwide to investigate and/or optimize biodiesel production from renewable lipid sources and ethanol derived from sugarcane (ethyl esters). Once implemented, this program will not only decrease our dependence on petroleum derivatives but also create new market opportunities for agribusiness, opening new jobs in the countryside, improving the sustainability of our energy matrix, and helping the Brazilian government to support important actions against poverty. This article discusses the efforts to develop the Brazilian biodiesel program in the context of technical specifications as well as potential oilseed sources.

Sugarcane bagasse and straw can be converted into pulps, oils, controlled-release formulations, chelating agents, and composites. This article reviews bagasse and straw conversion efforts in Brazil. Laboratory-scale processes were developed aiming at the integral use of these biomass byproducts. Organosolv pulping and oxidation of lignin are the most promising processes for the rational use of sugarcane residues. Fungal pretreatment and spec-troscopic characterization are also discussed.

Cyclohexanone monooxygenase (CHMO) catalyzing Baeyer-Villiger oxidation converts cyclic ketones into optically pure lactones, which have been used as building blocks in organic synthesis. A recombinant BL21(DE3)/pMM4 expressing CHMO originated from sp. NCIB 9871 was used to produce e-caprolactone through a simultaneous biocatalyst production and Baeyer-Villiger oxidation (SPO) process. A fed-batch process was designed to obtain high cell density for improving production of ε-caprolactone. The fed-batch SPO process gave the best results, 10.2 g/L of ε-caprolactone and 0.34 g/(L · h) of productivity, corresponding to a 10.5- and 3.4-fold enhancement compared with those of the batch SPO, respectively.