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Lim S.-H.,Industrial Biotechnology Research Center | Lim S.-H.,Chungnam National University | Ryu J.-M.,Biotechnology Process Engineering Center | Lee H.,Biotechnology Process Engineering Center | And 3 more authors.
Bioresource Technology | Year: 2011

A strain of Saccharomyces cerevisiae, KCCM50549, was found to efficiently ferment the inulin-containing carbohydrates in Jerusalem artichoke without acidic or enzymatic pretreatment prior to fermentation. S. cerevisiae KCCM50549 could utilize almost completely the fructo-oligosaccharides present in Jerusalem artichoke (up to degree of polymerization (DP) of 15), in contrast to the other S. cerevisiae strain such as NCYC625 that fermented the fructo-oligosaccharides with DP of up to around six. Inulin-fermenting S. cerevisiae KCCM50549 produced c.a. 1.6 times more ethanol from Jerusalem artichoke compared with S. cerevisiae NCYC625. Direct ethanol fermentation of Jerusalem artichoke flour at 180. g/L without any supplements or pretreatments by S. cerevisiae KCCM50549 in a 5. L jar fermentor yielded 36.2. g/L of ethanol within 36. h. The conversion efficiency of inulin-type sugars to ethanol was 70% of the theoretical ethanol yield. © 2010 Elsevier Ltd.


PubMed | University Putra Malaysia, University of Malaya and Industrial Biotechnology Research Center
Type: Journal Article | Journal: Biosensors | Year: 2016

A phenolic biosensor based on a zirconium oxide/polyethylene glycol/tyrosinase composite film for the detection of phenolic compounds has been explored. The formation of the composite film was expected via electrostatic interaction between hexacetyltrimethylammonium bromide (CTAB), polyethylene glycol (PEG), and zirconium oxide nanoparticles casted on screen printed carbon electrode (SPCE). Herein, the electrode was treated by casting hexacetyltrimethylammonium bromide on SPCE to promote a positively charged surface. Later, zirconium oxide was mixed with polyethylene glycol and the mixture was dropped cast onto the positively charged SPCE/CTAB. Tyrosinase was further immobilized onto the modified SPCE. Characterization of the prepared nanocomposite film and the modified SPCE surface was investigated by scanning electron microscopy (SEM), Electrochemical Impedance Spectroscopy (EIS), and Cyclic voltamogram (CV). The developed biosensor exhibits rapid response for less than 10 s. Two linear calibration curves towards phenol in the concentrations ranges of 0.075-10 M and 10-55 M with the detection limit of 0.034 M were obtained. The biosensor shows high sensitivity and good storage stability for at least 30 days.


Hashim P.,University Putra Malaysia | Sidek H.,Industrial Biotechnology Research Center | Helan M.H.M.,Industrial Biotechnology Research Center | Sabery A.,Industrial Biotechnology Research Center | And 2 more authors.
Molecules | Year: 2011

Leaves of Centella asiatica (Centella) were analysed for their triterpene composition and bioactivity such as collagen enhancement, antioxidant, anticellulite and UV protection capacity properties. Triterpenes of Centella were measured using HPLCPAD on an Excil ODS 5 μm (C18) column for the simultaneous determination of asiatic acid, madecassic acid, asiaticoside and madecassoside. Centella was found to contain significant amounts of madecassoside (3.10 ± 4.58 mg/mL) and asiaticoside (1.97 ± 2.65 mg/mL), but was low in asiatic and madecassic acid. The highest collagen synthesis was found at 50 mg/mL of Centella extracts. The antioxidant activity of Centella (84%) was compared to grape seed extract (83%) and Vitamin C (88%). Its lipolytic activity was observed by the release of glycerol (115.9 μmol/L) at 0.02% concentration. Centella extracts exhibited similar UV protection effect to OMC at 10% concentration. In view of these results, the potential application of Centella in food and pharmaceutical industries is now widely open. © 2011.


Shankar R.,University of Technology Malaysia | Madihah M.S.,University of Technology Malaysia | Shaza E.M.,University of Technology Malaysia | Nur Aswati K.O.,University of Technology Malaysia | And 2 more authors.
Carbohydrate Polymers | Year: 2014

The production of pullulanase by Bacillus flavothermus KWF-1 in batch and fed batch culture were compared using 2 L bioreactor. In batch culture, 0.0803 U/mL of pullulanase activity with specific activity of 0.0213 U/mg was produced by controlling the agitation speed and temperature at 200 rpm and 50 C, respectively. Fed batch production was studied by feeding the culture with different sago starch concentrations in various feeding modes for enhanced pullulanase production. Exponential feeding mode at dilution rate of 0.01/h was the preeminent strategy for enhanced pullulanase production of 0.1710 U/mL with specific activity of 0.066 U/mg. It had shown an increment of pullulanase production and specific activity by 2.1 and 3.1-fold, respectively when compared to batch culture. Increment of pullulanase activity in exponential feeding mode improved hydrolyzation of sago starch into maltotriose and panose by 4.5 and 2.5-fold respectively compared to batch system. © 2013 Elsevier Ltd.


Ujang Z.,Industrial Biotechnology Research Center | Rashid A.H.A.,Industrial Biotechnology Research Center | Suboh S.K.,Industrial Biotechnology Research Center | Halim A.S.,Universiti Sains Malaysia | Lim C.K.,Skin Research and Innovation Center
Journal of Applied Biomaterials and Functional Materials | Year: 2014

Background: The physical and biological characteristics of oligochitosan (O-C) film, including its barrier and mechanical properties, in vitro cytotoxicity and in vivo biocompatibility, were studied to assess its potential use as a wound dressing. Methods: Membrane films were prepared from water-soluble O-C solution blended with various concentrations of glycerol to modify the physical properties of the films. In vitro and in vivo biocompatibility evaluations were performed using primary human skin fibroblast cultures and subcutaneous implantation in a rat model, respectively. Results: Addition of glycerol significantly influenced the barrier and mechanical properties of the films. Water absorption capacity was in the range of 80%-160%, whereas water vapor transmission rate varied from 1,180 to 1,618 g/m2 per day. Both properties increased with increasing glycerol concentration. Tensile strength decreased while elongation at break increased with the addition of glycerol. O-C films were found to be noncytotoxic to human fibroblast cultures and histological examination proved that films are biocompatible. Conclusion: These results indicate that the membrane film from O-C has potential application as a wound-dressing material. © 2014 Società Italiana Biomateriali.


Lim S.J.,National University of Malaysia | Wan Aida W.M.,National University of Malaysia | Maskat M.Y.,National University of Malaysia | Mamot S.,National University of Malaysia | And 2 more authors.
Food Hydrocolloids | Year: 2014

The objective of this research was to screen and isolate fucoidan from Malaysian seaweeds and subsequently determine its antioxidant capacity. A screening test employing a colorimetric method was conducted on five types of Malaysian brown and red seaweeds. It was found that Sargassum binderi contained the highest fucoidan content (6.16±0.08%). Thus, fucoidan was isolated from S. binderi (yield 7.5%, purity 89.63%) for the determination of its antioxidant capacity. The isolated fucoidan was identified using high performance anion exchange chromatography (HPAEC) and attenuated total reflectance Fourier transform infra-red (ATR-FTIR) spectroscopy. The antioxidant assays performed were total phenolic content (TPC), free-radical scavenging activity (DPPH), reducing power, superoxide anion scavenging activity (SOA) and hydroxyl radical scavenging activity (OH). The antioxidant capacity of the extracted fucoidan (Fsar) was compared with those of a commercial food-grade fucoidan (Fysk) and of BHA, BHT and ascorbic acid. All the antioxidant assays performed showed either Fsar has significantly higher (p<0.05) or do not differ significantly (p>0.05) in activities compared to that of Fysk. At the same time, both Fsar and Fysk showed significant (p<0.05) antioxidant capacity in terms of superoxide anion and hydroxyl radical scavenging activities compared to those of the synthetic antioxidants. This shows that Fsar has the potential to be commercialised as a functional food product or as bioingredients with high antioxidative properties. © 2014 Elsevier Ltd.


PubMed | National Blood Center, Universiti Sains Malaysia and Industrial Biotechnology Research Center
Type: Controlled Clinical Trial | Journal: Thrombosis research | Year: 2015

Von Willebrand disease (vWD) is the second least common hemostatic disorder in Malaysia, and it has a low prevalence. This study examined the underlying platelet thrombogenicity cascades in the presence of different formulations of chitosan-derivatives in vWD patients. This paper aimed to determine the significant influence of chitosan biomaterial in stimulating the platelet thrombogenicity cascades that involve the von Willebrand factor, Factor 8, Thromboxane A2, P2Y12 and Glycoprotein IIb/IIIa in vWD.Variable chitosan formulations of N,O-Carboxymethylchitosan (NO-CMC) and Oligo-Chitosan (O-C) were tested. Fourteen vWD subjects voluntarily participated in this study after signing informed consent forms. The patients demographic profiles, family history, type of vWD, clinical symptoms and laboratory profiles were recorded and analyzed. Enzyme-linked immunosorbent assay, flow cytometry and Western blot tests were used to determine the level of the chitosan-adhered-platelet-mechanisms.The study revealed that most patients were predominantly affected by vWD type I. The O-C group of chitosans scaffold pores is sufficient to allow for nutrients and cells. The O-C-stimulated-mediators are capable of initiating the platelet actions and were detected to expedite the blood coagulation processes. The oligo-group of chitosans was capable of amplifying and triggering more platelet activators pathways via the studied mediators. The present findings suggest that the ability of each type of chitosan to coagulate blood varies depending on its chemical composition.The oligo group of chitosans is potentially capable of triggering platelet thrombogenicity cascades by activating platelets in vWD patients to form a platelet plug for hemostasis process.


PubMed | University Putra Malaysia, National University of Malaysia and Industrial Biotechnology Research Center
Type: | Journal: Biosensors & bioelectronics | Year: 2015

A novel optical detection system consisting of combination of uricase/HRP-CdS quantum dots (QDs) for the determination of uric acid in urine sample is described. The QDs was used as an indicator to reveal fluorescence property of the system resulting from enzymatic reaction of uricase and HRP (horseradish peroxidase), which is involved in oxidizing uric acid to allaintoin and hydrogen peroxide. The hydrogen peroxide produced was able to quench the QDs fluorescence, which was proportional to uric acid concentration. The system demonstrated sufficient activity of uricase and HRP at a ratio of 5U:5U and pH 7.0. The linearity of the system toward uric acid was in the concentration range of 125-1000 M with detection limit of 125 M.


PubMed | National Blood Center Jalan Tun Razak, Universiti Sains Malaysia and Industrial Biotechnology Research Center
Type: Journal Article | Journal: International journal of clinical and experimental medicine | Year: 2015

Chitosan-derived biomaterials have been reported to adhere when in contact with blood by encouraging platelets to adhere, activate and aggregate at the sites of vascular injury, thus enhanced wound healing capacity. This study investigated platelet morphology changes and the expression level of transforming growth factor-1 (TGF-1) and platelet-derived growth factor-AB (PDGF-AB) in the adherence of two different types of chitosans in von Willebrand disease (vWD): N,O-carboxymethylchitosan (NO-CMC) and oligo-chitosan (O-C). Fourteen vWD voluntary subjects were recruited, and they provided written informed consent. Scanning electron microscopy and enzyme-linked immunosorbent assay test procedures were employed to achieve the objective of the study. The results suggest that the O-C group showed dramatic changes in the platelets behaviors. Platelets extended filopodia and generated lamellipodia, leading to the formation of grape-like shaped aggregation. The platelet aggregation occurred depending on the severity of vWD. O-C was bound to platelets on approximately 90% of the surface membrane in vWD type 1; there was 70% and 50% coverage in vWD type II and III, respectively. The O-C chitosan group showed an elevated expression level of TGF-1 and PDGF-AB. This finding suggests that O-C stimulates these mediators from the activated platelets to the early stage of restoring the damaged cells and tissues. This study demonstrated that the greater expression level of O-C assists in mediating the cytokine complex networks of TGF-1 and PDGF-AB and induces platelet activities towards wound healing in vWD. With a better understanding of chitosans mechanisms of action, researchers are able to accurately develop novel therapies to prevent hemorrhage.


PubMed | University Putra Malaysia, University of Kuala Lumpur, University of Malaya and Industrial Biotechnology Research Center
Type: | Journal: Journal of ethnopharmacology | Year: 2016

Piper betle L. (PB) belongs to the Piperaceae family. The presence of a fairly large quantity of diastase in the betel leaf is deemed to play an important role in starch digestion and calls for the study of weight loss activities and metabolite profile from PB leaf extracts using metabolomics approach to be performed. PB dried leaves were extracted with 70% ethanol and the extracts were subjected to five groups of rats fed with high fat (HF) and standard diet (SD). They were then fed with the extracts in two doses and compared with a negative control group given water only according to the study protocol. The body weights and food intakes were monitored every week. At the end of the study, blood serum of the experimental animal was analysed to determine the biochemical and metabolite changes. PB treated group demonstrated inhibition of body weight gain without showing an effect on the food intake. In serum bioassay, the PB treated group (HF/PB (100mg/kg and 500mg/kg)showed an increased in glucose and cholesterol levels compared to the Standard Diet (SD/WTR) group, a decrease in LDL level and increase in HDL level when compared with High Fat Diet (HF/WTR) group. For metabolite analysis, two separation models were made to determine the metabolite changes via group activities. The best separation of PCA serum in Model 1 and 2 was achieved in principle component 1 and principle component 2. SUS-Plot model showed that HF group was characterized by high-level of glucose, glycine and alanine. Increase in the -hydroxybutyrate level similar with SD group animals was evident in the HF/PB(500mg/kg) group. This finding suggested that the administration of 500mg/kg PB extracts leads to increase in oxidation process in the body thus maintaining the body weight and without giving an effect on the appetite even though HF was continuously consumed by the animals until the end of the studies and also a reduction in food intake, thus maintaining their body weight although they were continuously consumed HF.

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