BUKU ABSTRAK - Universiti Putra Malaysia

Science, Technology & Engineering
Keywords: Heavy metal detector, colorimetric
Xylopia Leaf Oil - A Potential Care Product Ingredient
Assoc. Prof. Dr. Mohd. Puad Abdullah
Siti Humeirah Ab Ghani, Nor Azah Mohd. Ali, Mailina Jamil, Mastura Mokhtar and Muhajir Hamid
Faculty of Biotechnology and Biomolecular Sciences, University Putra Malaysia,
43400 UPM Serdang, Selangor, Malaysia.
+603-8946 7478; puad@biotech.upm.edu.my
The essential oils from the leaves of three local Xylopia species (Xylopia malayana, X. fusca and X. elliptica)
were analysed for their antimicrobial properties, cytotoxic effects and chemical compositions. The antimicrobial
activity was evaluated by using the broth dilution method against eleven strains of microorganism while the
cytotoxic effects were evaluated by the MTT assay. Our data showed that the oils possess moderate to high
degrees of antibacterial and antifungal activities towards all the microorganisms tested, particularly against the
multi-resistant Staphylococcus aureus and dermatophytes fungi. Cytotoxicity test on two human skin-derived cell
lines - Chang liver and CRL-1177, proved that the oils were not toxic to human cells. Using the GC-MS method,
we have identified more than fifty different chemical constituents in the leaf oils, representing 78.8%-94.4% of
the total oil. ?-pinene (42.0%), ?-pinene (15.2%), elemol (11.6%) and bicyclogermacrene (5.2%) were abundant
in Xylopia malayana; germacrene D (17.0%), bicyclogermacrene (12.0%), ?-elemene (11.5%) and ?-pinene
(10.1%) were major constituents in X. fusca; whereas, bicyclogermacrene (11.5%), sabinene (10.6%), ?-pinene
(9.0%), elemol (8.1%) and ?-pinene (5.4%) made the main components of X. elliptica oil. Subject to further
pharmacodynamic and safety evaluations, our findings support the possible use of Xylopia leaf oils as a safer
alternative to synthetic active ingredient for personal care products. In addition, the unique chemical constituents
of the individual oil can be used as a chemotaxonomic guide for the identification of the genus Xylopia.
Keywords: Xylopia species, antimicrobial activity, in vitro cytotoxicity, leaf essential oils
Portable Heavy Metal Detector
Assoc. Prof. Dr. Nor Azah Yusof
Norhisam Misron and Raja Nor Firdaus Kashfi Raja Othman
Faculty of Science, University Putra Malaysia,
43400 UPM Serdang, Selangor, Malaysia.
+603-8946 6782; azah@science.upm.edu.my
The invention is about development of a new rapid, portable, inexpensive detection heavy metal detector
based on color detection system. The detection scheme is based on the color changes of the chromogenic reagent
that reacts with toxic metals. The color changes will be detected by a photodiode or phototransistor sensor. The
photodiode or phototransistor sensor will produce electrical signal which will be processed by a microcontroller.
The microcontroller will display the level of quantity of toxic metal that reflects the safety of that liquid samples.
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