In order to decolourise olive oil mill wastewaters (OOMW) efficiently, production and differentia... more In order to decolourise olive oil mill wastewaters (OOMW) efficiently, production and differential induction of ligninolytic enzymes by the white rot Coriolopsis polyzona, were studied by varying growth media composition and/or inducer addition. Among various possible inducers, veratryl alcohol appeared to be the most efficient to enhance specific productions of lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase by a factor of 18.5, 20.8 and 55, respectively. Ligninolytic enzymes were better produced in glucose based medium with a low nitrogen level (2.2 mM) under O 2 atmosphere. The addition of 5 mM veratryl alcohol resulted in a maximal production of LiP, whereas maximal MnP and laccase were obtained at 10 mM. LiP production was totally repressed in presence of 100 lM Mn 2+ . The extrapolation of these conditions on OOMW based media was carried out at different effluent dilutions and the possible role of the different ligninolytic enzymes in OOMW decolourisation was studied. A better effluent decolourisation was obtained under LiP induction condition (5 mM veratryl alcohol) than when LiP was repressed (100 lM Mn 2+ ). Furthermore, high levels of laccase had a detrimental effect on OOMW decolourisation concomitant to the formation of soluble polymeric aromatic compounds.
The use of probiotics has become widely accepted as a natural means to promote health for both hu... more The use of probiotics has become widely accepted as a natural means to promote health for both humans and animals. Today, probiotics are used as health supplements in food and feeds and they are replacing the use of antibiotic growth promotors or chemical supplements. Under the right conditions the claims made for probiotic preparations can be realized. The development of suitable technology for probiotic production, taking into account viability and stability, is a key area of research for industrial production. Production of probiotics should be based on the microbial criteria, and the ability to withstand stress during processing and storage of products is important. Thermophilic/thermotolerant probiotics are of great interest in this area as they can have all the desired characteristics. This review makes an overview of probiotic selection studies including new technologies for isolation/identification, adhesion and immune response. The importance of multistrain cultures is also stressed. The development of suitable probiotics in food and feed needs good proof of their efficacy and function in order to be accepted as a valuable product.
In order to decolourise olive oil mill wastewaters (OOMW) efficiently, production and differentia... more In order to decolourise olive oil mill wastewaters (OOMW) efficiently, production and differential induction of ligninolytic enzymes by the white rot Coriolopsis polyzona, were studied by varying growth media composition and/or inducer addition. Among various possible inducers, veratryl alcohol appeared to be the most efficient to enhance specific productions of lignin peroxidase (LiP), manganese peroxidase (MnP) and laccase by a factor of 18.5, 20.8 and 55, respectively. Ligninolytic enzymes were better produced in glucose based medium with a low nitrogen level (2.2 mM) under O 2 atmosphere. The addition of 5 mM veratryl alcohol resulted in a maximal production of LiP, whereas maximal MnP and laccase were obtained at 10 mM. LiP production was totally repressed in presence of 100 lM Mn 2+ . The extrapolation of these conditions on OOMW based media was carried out at different effluent dilutions and the possible role of the different ligninolytic enzymes in OOMW decolourisation was studied. A better effluent decolourisation was obtained under LiP induction condition (5 mM veratryl alcohol) than when LiP was repressed (100 lM Mn 2+ ). Furthermore, high levels of laccase had a detrimental effect on OOMW decolourisation concomitant to the formation of soluble polymeric aromatic compounds.
The use of probiotics has become widely accepted as a natural means to promote health for both hu... more The use of probiotics has become widely accepted as a natural means to promote health for both humans and animals. Today, probiotics are used as health supplements in food and feeds and they are replacing the use of antibiotic growth promotors or chemical supplements. Under the right conditions the claims made for probiotic preparations can be realized. The development of suitable technology for probiotic production, taking into account viability and stability, is a key area of research for industrial production. Production of probiotics should be based on the microbial criteria, and the ability to withstand stress during processing and storage of products is important. Thermophilic/thermotolerant probiotics are of great interest in this area as they can have all the desired characteristics. This review makes an overview of probiotic selection studies including new technologies for isolation/identification, adhesion and immune response. The importance of multistrain cultures is also stressed. The development of suitable probiotics in food and feed needs good proof of their efficacy and function in order to be accepted as a valuable product.
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