UCSI University              
English    |    中文    |    Русский    |    العربية
ePayment   |    LMS Sign In   |    UCSI Group   |    UCSI University Trust
Home Current Students Alumni Staff Parents
Home  > Faculty of Applied Sciences > Student Testimonials > Postgraduate Students
Postgraduate Students
In another milestone for the Faculty of Applied Sciences, three of its graduate students have earned the first master’s degree by research offered by UCSI University. Receiving their Master in Applied Sciences by Research from the faculty in August 2013 these students, who are the pioneering batch of the programme, are also UCSI University scholarship holders. Their success is testament to our research capabilities and we wish them the heartiest congratulations upon their graduation in October 2013.

The following are highlights of their research experience and findings:
Tan Yuen Ping

Thesis title: Antioxidant, antityrosinase, antibacterial and anti-quorum sensing activities of selected ulam herbs in Malaysia

Research experience: “My greatest joy was the successful isolation of methyl gallate with potent anti-QS properties from cashew leaves. The research work was novel and completed on time. Three manuscripts have been submitted for publication in international refereed journals. I owe much of this success to my outstanding supervisor for whom I have great respect.”

Research findings: Out of six species of fresh ulam herbs screened for antioxidant, antityrosinase and antibacterial activities, Anacardium occidentale (cashew) leaves had the highest values. Piper betle (betel) leaves displayed negative tyrosinase inhibition, suggesting tyrosinase enhancement effect and melanogenic or skin-darkening properties. Cashew leaves possessed the strongest antibacterial activity while broad-spectrum inhibition was observed in betel leaves. Both species showed substantial quorum sensing (QS) inhibition against Chromobacterium violaceum.

Blanching and microwave treatment had variable effects on the antioxidant, antityrosinase and antibacterial properties of the herbs, which included significant loss, significant gain or unchanged. From the methanol leaf extract of cashew, methyl gallate (MG) was isolated by column chromatography, and identified by NMR and MS analyses. QS inhibition of MG was 14.5 ± 0.1 mm for mean diameter of violacein inhibition zone, and 0.006 mg/disc for minimum violacein inhibitory dose. Using reversed-phase HPLC, the content of MG was quantified as 183 ± 18 mg/100 g of leaves. This is the first report of QS inhibition in cashew and betel leaves. MG systematically isolated from cashew leaves had shown to possess potent anti-QS properties. Its anti-QS properties and toxicity warrants further research before MG can be considered as an anti-pathogenic drug.

Thesis title: Optimisation of ultrasonic-assisted extraction of kenaf seed and the antioxidant and cytotoxic activity and purification of phenolic compounds in the extract

Research experience: “I was successful in determining the antioxidant and cytotoxic activity of kenaf seed extract which has not been done before. Manuscripts have been submitted for publication in international refereed journals. I would like to thank my supervisor for her guidance along my research path.”

Research findings: Kenaf (Hibiscus cannabinus L.) is a valuable fibre and medicinal plant from the family Malvaceae. Over the last few years, kenaf plants have received significant attention in Malaysia. The conversion of the National Tobacco Board to the National Kenaf and Tobacco Board shows the Malaysian government’s commitment to develop the kenaf industry. However, the kenaf seed has always been considered by the industry as an agricultural waste. Therefore, it is justified to investigate the potential health function of the kenaf seed.

Based on antioxidant activities, the best parameter (ethanol concentration and extraction time) for extracting phenolic-enriched kenaf seed extract (KSE) obtained by pulsed ultrasonic-assisted extraction (PUAE) was 80% ethanol for 15 min. From cytotoxicity tests, KSE showed most effective inhibition towards cervical cancer (HeLa), followed by breast cancer (MCF-7), lung cancer (SK-LU1) and colon cancer (HCT-116) cells. KSE was stable in the gastric phase but highly sensitive to the conditions in the intestinal phase. The major phenolic acids presented in the purified KSE were sinapic acid, ferulic acid, catechin and tannic acid. In conclusion, the antioxidant and cytotoxic properties of KSE are worth further investigation before it can be used by the food and pharmaceutical industries as additives or supplements.
NG Shy Kai

Thesis title: Production of microencapsulated kenaf (Hibiscus cannabinus L.) seed oil with improved oxidative stability and bioavailability

Research experience: “The novelty of my research was to transform kenaf seed oil that is in liquid form into solid form, and enhanced its oxidative stability and bioavailability. I am glad that three manuscripts from my research work have been accepted for publication in international journals. This motivates me to obtain more research findings.”

Research findings: Kenaf seed oil was employed for microencapsulation in combination with coating materials including maltodextrin, sodium caseinate and emulsifier (soy lecithin). Different inlet air temperatures (160°C, 180°C and 200°C) at fixed total solid content of 30% and different total solid content in feed emulsion (20%, 30% and 40%) at 160°C were used for spray drying. The effects of these different parameters on the characterisation and oxidative stability were studied. The most oxidative stable microencapsulated kenaf seed oil (MKSO) was chosen and was compared with bulk (unencapsulated) kenaf seed oil in terms of their changes of fatty acids profile and bioactive compounds, such as phytosterols, tocopherols and phenolic acids upon accelerated storage. The controlled release behavior of MKSO in different pH medium and simulated gastrointestinal system was investigated. Phytochemical screening of kenaf seed oil and MKSO was done prior to in vivo study. Hypercholesterolemia diets were administered to the Sprague Dawley rats to determine the anti-hypercholesterolemic effects of both oil samples.

Results showed that both parameters and emulsion formulations significantly (p < 0.05) affected the characterisation and oxidative stability of MKSO. The best parameter and formulation were inlet air temperature of 160°C and 40% total solid content in feed emulsion, respectively. There was a significant decrease (p < 0.05) in bioactive compounds in bulk kenaf seed oil while the bioactive compounds in MKSO were maintained in a stable condition upon accelerated storage. The presence of phytochemicals and bioactive compounds facilitated the anti-hypercholesterolemic effects of both oil samples. This suggested the suitability of MKSO to be used as food supplements.
Site Map | Privacy Policy | Security Policy | © Copyright 2012. UCSI Education Sdn. Bhd. (185479-U). All rights reserved. A member of UCSI Group.
Facebook   Picasa   Twitter   Youtube   Instagram   Pinterest   Pinterest