**Acknowledgements**

We would like to thank the Director General of Health of Malaysia for his permission to publish this article and the Director of Institute for Medical Research (IMR), Kuala Lumpur for the support of this project. This work was financially supported by the NKEA AGRICULTURE (EPP#1), NKEA Research Grant Scheme (NRGS) (Grant No: NH1014D060). The author also thanks Dr.Aswir (IMR), Dr. Hussin (IMR) and Dr. Lee Han Lim (IMR) for critically reviewing this paper and technical support from Perkin Elmer Sdn Bhd. (Malaysia). The previous support of Islam Development Bank (IDB) for training in FTIR and 2DIR under the Merit Fellowship is gratefully acknowledged.
