BUKU ABSTRAK - Universiti Putra Malaysia

Development, Optimisation and Validation of RP-HPLC-FL Method for Simultaneous
Determination of Aflatoxins, Ochratoxin A and Zearalenone in Cereals
Prof. Dr. Jinap Selamat
Anosheh Rahmani
Faculty of Food Science and Technology, University Putra Malaysia,
43400 UPM Serdang, Selangor, Malaysia.
+603-8946 8393; jinap@food.upm.edu.my
This research has been conducted to develop a reverse phase high performance liquid chromatography
fluorescence detection (RP-HPLC-FL) method for simultaneous determination of six mycotoxins (aflatoxin B1,
B2, G1 and G2, ochratoxin A and zearalenone) in cereals. The developed method was then optimized using
fractional factorial design (FFD) followed by response surface methodology (RSM). The optimal conditions were
41% and 60% organic solvent at the start and end of gradient mobile phase, 1.92 and 0.2 methanol/acetonitrile
ratio at the start and end of gradient, respectively, 0.1% acid concentration in aqueous phase, at 1 ml/min flow
rate and column temperature of 40oC. In addition, the efficiency of three extraction solvents and three clean-up
procedures (OASIS HLB, MycoSep and multi-functional immunoaffinity column) were compared in spiked rice
sample. The highest recovery of mycotoxins was obtained by using methanol water (80:20 v/v) as extraction
solvent mixture and multi-functional immunoaffinity column as clean-up method. Application of best solvent
extraction in combination with optimization of IAC produced recovery rates of 87, 104, 93, 97, 94 and 97% for
aflatoxin B1, B2, G1, G2, OTA and ZEA, respectively. Application of optimized simultaneous determination
method on spiked cereal samples showed 74-104 % recovery for all six mycotoxins and acceptable precision
in all cereals include of rice, barley, oat, maize and wheat. Validation of the optimized HPLC- FL method was
carried out through determination of selectivity, sensitivity, linearity and precision. Finally, in order to confirm the
performance and validity of HPLC method for simultaneous determination of mycotoxins on real cereal samples,
a total of 61 samples of cereals were randomly collected from supermarket and analyzed by HPLC and liquid
chromatography tandem mass spectroscopy (LC-MS/MS). The results clearly demonstrated high correlation
between HPLC and LC-MS/MS determinations. The results also showed low occurrence of these mycotoxins in
commercial cereals marketed in Malaysia.
Keywords: Mycotoxin determination; high performance, liquid, chromatography fluorescence detection (RP-HPLC-FL), cereal
Defatted Kenaf Seed as a Potential Source of Protein in Food Industry
Prof. Dr. Maznah Ismail
Siti Farhana Fathy and Abdalbasit Adam Mariod
Institute of Bioscience, University Putra Malaysia,
43400 UPM Serdang, Selangor, Malaysia.
+603-8947 2115; maznahis@medic.upm.edu.my
Kenaf (Hibiscus Cannabinus L.), family malvaceae has been receiving an increasing attention from
manufacturers due to its broad applications in fiber board, biocomposite materials and animal feed. There are
however many by-products of Kenaf that are not used such as its seeds, leaf and roots. Worldwide, many research
have concentrated on finding various sources of plant proteins that may help in increasing the nutritional value of
food products at low cost. Kenaf seed, after oil extraction using systemic fluid extraction (SFE), leaves defatted
sample as a waste by-product. The relatively ample protein concentrates obtained from defatted Kenaf seed
suggested that defatted Kenaf seed could be used as a new source of protein. In this study, two varieties of defatted
Kenaf seed, QP3 and V36 were used. Results show that protein concentrates of QP3 had a great potential to serve
as an excellent source of edible protein owing to its high water absorption capacity (4.99 g/g) and oil absorption
capacity (8.71 g/g). High water absorption of proteins helps to reduce moisture loss in food products while high
oil absorption is essential in the formulation of food systems like sausages, cake batters, mayonnaise and salad
dressings. Protein concentrates of QP3 also have higher foaming capacity and stability compared to V36 thus
can form an excellent base for high sugar food systems like cake batters, beverages, whipped toppings, frozen
desserts and confections. On the other hand, V36, due to its high content in its protein concentrates (81.4%),
has the potential to replace other protein source. Hence, protein concentrates obtained from defatted Kenaf seed
QP3, and V36 exhibit satisfactory functional properties as required in food processes, and therefore has a bright
prospect of applications in the food industry.
Keywords: Hibiscus cannabinus, defatted, protein concentrates, oil absorption, water absorption, foaming properties
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Food