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Ph.D. Department of Biochemistry, 1990. Obafemi Awolowo University, ILE – IFE, Nigeria MSc. Department of Biochemistry, 1986. University of Nairobi, Kenya MSc. Department of Biochemistry, 1983. Faculty of Chemistry Donestk State University, USSR Language Certificate :Varonezh State University, USSR, 1977 Preparatory Faculty 1986 Pharmacia/ICIPE Certificate in biochemical separation techniques
Biotechnology and industrial products formulary
Biosensors in: Handbook of Food Safety Engineering - 2011
Food safety engineering is an emerging multidisciplinary field of applied physical sciences combining engineering knowledge and skills with food microbiology and safety. It aims to develop various processing techniques and hurdles in complex processes that are capable of addressing food safety challenges, with minimum alteration in food quality and nutritional value. Although in today’s competitive market, the food industry has strived to provide a wide variety of products with enhanced shelf-life, functionality and quality attributes in order to meet versatile consumer demands, concerns about food safety is still overwhelming among consumers, retailers, and the food industry. Such concerns accentuate the rapid developments in the specialisation of food safety engineering, as in recent years, it has become clear that engineering approaches and methods play a critical role in the development and application of rapid and reliable techniques for microbial pathogen detection and inactivation. Therefore there is an urgent need for a book devoted to this emerging area.
In order to meet the market demands, it is timing to publish Handbook of Food Safety Engineering. The book is divided into four parts, which begins with Part I detailing the principles of food safety including microbial growth and modelling, followed by Part II covering new food safety detection methods. Part III and Part IV discussing various traditional and novel thermal and non-thermal processing techniques for microbial inactivation. The book is concluded with Part IV on food safety management systems such as GMP, SSOP, HACCP and ISO22000.
As the first book in the subject area, Handbook of Food Safety Engineering is written by the most active international peers in the subject area with both academic and professional credentials. The book is intended to provide the engineer and technologist working in research, development, and operations in the food industry with critical and readily accessible information on the art and science of the emerging food safety engineering. The book should also serve as an essential reference source to undergraduate and postgraduate students and researchers in universities and research institutions.
Handbook of Food Safety Engineering
Enrichment of PUFA in Nile perch free fatty acids by selective enzymatic esterification and subsequent analysis using HPLC-ELSD - 2011
PUFA from oil extracted from Nile perch viscera were enriched by selective enzymatic esterification of the free fatty acids (FFA) or by hydrolysis of ethyl esters of the fatty acids from the oil (FA-EE). Quantitative analysis was performed using RP-HPLC coupled to an evaporative light scattering detector (RP-HPLC-ELSD). The lipase from Thermomyces lanuginosus discriminated against docosahexaenoic acid (DHA) most, resulting in the highest DHA/DHA-EE enrichment while lipase from Pseudomonas cepacia discriminated against eicosapentaenoic acid (EPA) most, resulting in the highest EPA/EPA-EE enrichment. The lipases discriminated between DHA and EPA with a higher selectivity when present as ethyl esters (EE) than when in FFA form. Thus when DHA/EPA were enriched to the same level during esterification and hydrolysis reactions, the DHA-EE/EPA-EE recoveries were higher than those of DHA/EPA-FFA. In reactions catalysed by lipase from T. lanuginosus, at 26 mol% DHA/DHA-EE, DHA recovery was 76% while that of DHA-EE was 84%. In reactions catalysed by lipase from P. cepacia, at 11 mol% EPA/EPA-EE, EPA recovery was 79% while that of EPA-EE was 92%. Both esterification of FFA and hydrolysis of FA-EE were more effective for enriching PUFA compared to hydrolysis of the natural oil and are thus attractive process alternatives for the production of products highly enriched in DHA and/or EPA. When there is only one fatty acid residue in each substrate molecule, the full fatty acid selectivity of the lipase can be expressed, which is not the case with triglycerides as substrates.
European Journal of Lipid Science and Technology. 29 MAR 2011 DOI: 10.1002/ejlt.201000560Read More..
Enzymatic Synthesis of Lipophilic Rutin and Vanillyl Esters From Fish By Products. Accepted - 2011
Lipase-catalyzed synthesis of lipophilic phenolic antioxidants was carried out with a concentrate of n-3 polyunsaturated fatty acids (PUFAs), recovered from oil extracted from Salmon (Salmon salar) by-products. Vanillyl alcohol and rutin were selected for the esterification reaction and obtained esters yields were 60 and 30 %, respectively. The antioxidant activities of the esters were compared with those of commercial butylated hydroxytoluene (BHT) and α-tocopherol using DPPH radical scavenging and thiobarbituric acid assays. In DPPH assay, rutin esters showed better activity than vanillyl esters and on the contrary in lipophilic medium, vanillyl esters were found to be superior to rutin esters. In bulk oil system, the antioxidant activities of rutin and vanillyl derivatives were lower than that of BHT and α-tocopherol but in emulsion, they showed better activity than α-tocopherol. By attaching PUFAs to natural phenolics, the PUFAs are protected against oxidation while PUFA improves the hydrophobicity of the phenolic which could enhance its function in lipid systems.
J. Agric. Food Chem. 2011
The ‘LipoYeasts’ project: using the oleaginous yeast Yarrowia lipolytica in combination with specific bacterial genes for the bioconversion of lipids, fats and oils into high-value products - 2011
The oleochemical industry is currently still dominated
by conventional chemistry, with biotechnology only
starting to play a more prominent role, primarily with
respect to the biosurfactants or lipases, e.g. as detergents,
or for biofuel production. A major bottleneck
for all further biotechnological applications is the
problem of the initial mobilization of cheap and vastly
available lipid and oil substrates, which are then
to be transformed into high-value biotechnological,
nutritional or pharmacological products. Under the
EU-sponsored LipoYeasts project we are developing
the oleaginous yeast Yarrowia lipolytica into a versatile
and high-throughput microbial factory that, by
use of specific enzymatic pathways from hydrocarbonoclastic
bacteria, efficiently mobilizes lipids
by directing its versatile lipid metabolism towards
the production of industrially valuable lipid-derived
compounds like wax esters (WE), isoprenoid-derived
compounds (carotenoids, polyenic carotenoid ester),
polyhydroxyalkanoates (PHAs) and free hydroxylated
fatty acids (HFAs). Different lipid stocks (petroleum,
alkane, vegetable oil, fatty acid) and combinations
thereof are being assessed as substrates in combination
with different mutant and recombinant strains of
Y. lipolytica, in order to modulate the composition and
yields of the produced added-value products.
Microbial Biotechnology. 1751-7915.Read More..
Enzymatic enrichment of omega-3 polyunsaturated fatty acids in Nile perch (Lates niloticus) viscera oil - 2010
Oil was extracted from fatty material obtained from Nile perch viscera using the protease Protex 30L. Enrichment of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the glyceride fraction was carried out by hydrolysis of extracted oils with lipases from Candida rugosa, Thermomyces lanuginosus and Pseudomonas cepacia. The unusual fatty acid distribution of the oil influenced the apparent lipase specificity to a large extent. In the unhydrolysed oil, only 16% of EPA was in sn-2 position while 51% of palmitic acid was located in this position of the triacylglycerol (TAG) molecules. Non-regioselective lipase from C. rugosa was the most effective in combined enrichment of both EPA and DHA. This was partly because it was able to hydrolyse off palmitic acid from the sn-2 position, which 1-, 3-specific lipases were unable to do. Hydrolysis with C. rugosa lipase enriched EPA from 3 to 6 mol% and DHA from 9 to 23 mol%, with recoveries of 42 and 55%, respectively. The 1-, 3-specific lipase from T. lanuginosus was ineffective in enriching EPA, but gave best DHA enrichment, 38 mol% with a recovery of 39%. DHA was rather equally distributed in sn-1, -2 and -3 positions of TAG. The results show that both the fatty acid specificity and regiospecificity of the lipase as well as the fatty acid distribution of the oil should be considered when choosing the strategy for fatty acid enrichment.
European Journal of Lipid Science and Technology. Volume 112, Issue 9, pages 977–984, September 2010Read More..