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Bioethanol and biodiesel are currently the dominant bio-based fuels in transportation. Due to its superiority over ethanol, biobutanol has a great potential to become a replacement or additive compound of gasoline and diesel in the future. In this article, history, legislation, and demand for biofuels in general are described. Biobutanol production via acetone–butanol–ethanol fermentation and the latest research achievements in feedstock and process development are briefly pointed out. Novel catalytic approaches for ethanol-to-butanol process complementary to fermentation is shortly highlighted in the end.

There is a demand for the increased production and usage of biofuels from both environmental and a political point of view. Biobutanol has great potential to become a novel replacement fuel for gasoline and diesel or an additive compound of these fuels in the future. This chapter reveals the superior fuel properties of butanol over ethanol, including better energy content, usability, safety, and easier distribution of the fuel. Traditional biochemical (acetone-butanol-ethanol fermentation) and chemical production processes of butanol are reviewed. In addition, the novel production routes of biobutanol are highlighted. Challenges in the implementation of feasible biochemical production processes of butanol in industrial scale include cost of raw materials, low product yield from fermentation, and expensive processing techniques. Process development techniques and different methods in order to increase the yield of fermentative butanol production by means of for instance new processing technologies and metabolic engineering are discussed.

Lactoferrin (Lf) is a molecule naturally present in bovine milk that affects the availability and transport systems of iron. Lf also binds endotoxin (lipopolysaccharide, LPS) of Gram-negative bacteria and modulates the immunological response. In the present study, concentrations of bovine Lf (bLf) and citrate in milk were determined in early (EL) and late (LL) lactating dairy cows, using an experimentally induced endotoxin mastitis model and a crossover design. Nine clinically healthy Finnish Ayrshire cows were challenged twice with 100 μg endotoxin infused into one udder quarter. Milk samples were collected from the challenged and control quarters of each cow before and after endotoxin infusion during 3 d, and bLf and citrate concentrations were measured. In all cows, clinical signs of mastitis were seen at both times of challenge, but the response was more severe in EL than in LL. Concentration of bLf in the milk started to rise approximately 8 h after endotoxin infusion and was still higher than normal on the third day, especially in the late-lactating cows. In milk of the LL group, concentrations of bLf were significantly higher than in the EL group. In contrast, concentrations of citrate were higher in milk of the EL cows compared with the LL cows. Concentration of bLf and citrate varied substantially among cows. The molar ratio of citrate to bLf before and after challenge was significantly higher during the EL period. The results of this study partly explain why cows in early lactation are more susceptible to intramammary infections and why mastitis is more severe in them.

A polymorphism in the human prostate-specific glandular kallikrein (hKLK2) gene was described by direct sequencing (by PCR) of genomic DNAs isolated from prostatic cancer tissue, benign prostatic hyperplasia tissue, and blood leukocyte specimens. Results showed two forms of human prostate-specific glandular kallikrein protein (hK2), a consequence of a change from C to T at base 792 in the hK2 coding region. Producing the two forms as recombinant proteins in insect cells demonstrated that Arg226-hK2 (CC genotype) is an active protein and Trp226-hK2 (TT genotype) is inactive. Polymorphism studies of 36 patients with prostatic diseases identified only 1 with the TT genotype. The same kind of polymorphism was not detected in the human prostate-specific antigen (hKLK3) gene. Arg226-hK2 possessed only trypsin-like enzyme activity, whereas recombinant human prostate-specific antigen (hPSA) had only chymotrypsin-like activity. Monoclonal and polyclonal antibodies raised against hPSA purified from seminal plasma detected both active and inactive hK2. Thus, because inactive as well as stable hK2 protein may be present, a lack of trypsin-like activity in hPSA standards is not enough to confirm that the materials are free of hK2 contamination.

In this study manganese peroxidase (MnP) enzymes from selected white-rot fungi were isolated and compared for potential future recombinant production. White-rot fungi were cultivated in small-scale in liquid media and a simplified process was established for the purification of extracellular enzymes. Five lignin degrading organisms were selected (Bjerkandera sp., Phanerochaete (P.) chrysosporium, Physisporinus (P.) rivulosus, Phlebia (P.) radiata and Phlebia sp. Nf b19) and studied for MnP production in small-scale. Extracellular MnP activity was followed and cultivations were harvested at proximity of the peak activity. The production of MnPs varied in different organisms but was clearly regulated by inducing liquid media components (Mn2+, veratryl alcohol and malonate). In total 8 different MnP isoforms were purified. Results of this study reinforce the conception that MnPs from distinct organisms differ substantially in their properties. Production of the extracellular enzyme in general did not reach a substantial level. This further suggests that these native producers are not suitable for industrial scale production of the enzyme. The highest specific activities were observed with MnPs from P. chrysosporium (200 U mg-1), Phlebia sp. Nf b19 (55 U mg-1) and P. rivulosus (89 U mg-1) and these MnPs are considered as the most potential candidates for further studies. The molecular weight of the purified MnPs was estimated to be between 45–50 kDa.