The unsteady blood flow in the stenosed porous artery subjected to a magnetic field was studied analytically. Oscillating
pressure gradient and periodic body acceleration were imposed on the flow field. The effects of the magnetic field and
the permeability of the stenosed artery on the blood velocity were studied. The results showed that the magnetic field
affected the flow field significantly which can be beneficial for some practical problems.
MeSH terms: Arteries; Permeability; Pressure; Porosity; Magnetic Fields
Flavonoid is an industrially-important compound due to its high pharmaceutical and cosmeceutical values. However,
conventional methods in extracting and synthesizing flavonoids are costly, laborious and not sustainable due to small
amount of natural flavonoids, large amounts of chemicals and space used. Biotechnological production of flavonoids
represents a viable and sustainable route especially through the use of metabolic engineering strategies in microbial
production hosts. In this review, we will highlight recent strategies for the improving the production of flavonoids
using synthetic biology approaches in particular the innovative strategies of genetically-encoded biosensors for in
vivo metabolite analysis and high-throughput screening methods using fluorescence-activated cell sorting (FACS).
Implementation of transcription factor based-biosensor for microbial flavonoid production and integration of systems
and synthetic biology approaches for natural product development will also be discussed.
Nepenthes, locally known as ‘periuk kera’ in Malaysia, is a fascinating species due to uniqueness in their morphology
in having pitcher organ for carnivorous diet. The pitcher plant has been used for cooking traditional delicacies and
as traditional remedies to treat illness. Hence, this species might possess beneficial health properties. This study
aimed to compare the antioxidant activity of the pitcher extracts from Nepenthes ampullaria, Nepenthes rafflesiana
and their hybrid, Nepenthes × hookeriana. The samples were extracted using methanol:chloroform:water (3:1:1)
via sonication assisted extraction and the extracts were subjected to three different antioxidant assays, namely
2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing power (FRAP) and total phenolic content (TPC). Extract from N.
ampullaria exhibited the strongest radical scavenging activity (0.148 ± 0.04 mg/mL) with the highest ferric reducing
power (0.009 ± 0.003 mg GA/mg dry weight) among the three species, whereas that of N. rafflesiana possessed the
highest phenolic content (0.057 ± 0.017 mg GA/mg dry weight). However, the antioxidant capacities of the pitcher
extracts were not significantly different (p>0.05) between the three species and were much lower than the gallic acid
as a standard reference.
In this study oil palm empty fruit bunches (EFB) fibres was used to synthesize biophenolic resin (BPR) at a different
formaldehyde/liquefied empty fruit bunches (F/LEFB) molar ratio which is 1.0, 1.5 and 2.0. The higher molar ratio of F/
LEFB used has resulted in an increased of viscosity and solid content of BPR resin. The first decomposition of BPR resin
occured around 86 to 130°C due to the evaporation of low molecular weight substance which were water, free phenol
and formaldehyde. Glass fibre reinforced biophenolic composite (BPC) and glass fibre reinforced biophenolic elastomer
composite (BPEC) was successfully fabricated using BPR resin. The impact strength and flexural strain of BPEC were
higher than that of BPC. The impact strength of BPEC 1.5 was the highest at 47.71 kJm-2. However, the flexural strength
of BPEC was lower compared with BPC, which the highest flexural strength was obtained by BPC 1.0 at 65.18 MPa. The
cross-sectional image from scanning electron microscope (SEM) of BPEC and BPC confirmed the presence of epoxidized
natural rubber (ENR) improved the compatibility between glass fibre and BPR resin.
Basal stem rot disease of oil palm caused by Ganoderma boninense is one of the most devastating diseases in oil palm
plantation resulting in low yield, loss of palm stands and shorter replanting cycle. To-date, there is no effective treatment
for Ganoderma infected palms. Control measures, either chemical or cultural approaches, show varying degrees of
effectiveness. The application of biological control agents which is environmental-friendly could be an attractive solution
to overcome the problem. Earlier, we had isolated a mycoparasite, Scytalidium parasiticum, from the basidiomata of
Ganoderma boninense. In vitro assay and nursery experiment showed that this fungus could suppress Ganoderma infection
and reduce disease severity. However, metabolites which might contribute to the antagonistic or mycoparasitic effect
remain unknown. In the current study, optimization of fungal sample processing, extraction, and analytical procedures
were conducted to obtain metabolites from the maize substrate colonized by mycoparasitic ascomycetous Scytalidium
parasiticum. This technique capable of producing sexual spores in sac-like organs. Untargeted metabolomics profiling
was carried out by using Liquid Chromatography Time of Flight Mass Spectrometry (LC-ToF-MS). We found that
S. parasiticum in both liquid- and solid-state cultivation gave higher metabolite when extracted with 60% methanol with
1% formic acid in combination with homogenisation methods such as ultrasonication and grinding. The findings from
this study are useful for optimisation of metabolite extraction from other fungi-Ganoderma-plant interactions.
MeSH terms: Methanol; Chromatography, Liquid; Zea mays; Formates; Mass Spectrometry; Spores, Fungal; Plant Stems; Arecaceae; Ganoderma; Metabolomics; Biological Control Agents
In this paper, Taguchi experimental design technique was applied for optimization of chromium (Cr)/silver (Ag)/indium
tin oxide (ITO) SPR sensor for operation in near infrared region. Four factors were considered which include wavelength,
thickness of Cr, thickness of Ag, and thickness of ITO. Finite-difference-time-domain (FDTD) method was used in numerical
analysis for minimum reflectance (Rmin) and full-width-at-half-maximum (FWHM) performance parameters. The results
obtained from the Taguchi method shows that the optimized parameter for Rmin was 785 nm of wavelength, Cr (1 nm),
Ag (40 nm) and ITO (20 nm), whereas the optimized parameter for FWHM was 785 of wavelength, Cr (0 nm), Ag (40 nm)
and ITO (0 nm). In short, the optimum parameters for achieving the desired performance of sensor were successfully
predicted using Taguchi optimization method.
MeSH terms: Chromium; Indium; Paper; Research Design; Silver; Tin Compounds
Sesquiterpenes are a three-isoprene unit compounds which belong to terpenoid family of secondary metabolites. These
volatile compounds are one of the major constituents of essential oils in plants and plays major roles in plant signaling
of defense mechanism. The effects of methyl jasmonate (MeJA) concentrations (100 and 200 μM) on the production
of sesquiterpene compounds after incubation period for 1, 3, and 6 days were investigated in Persicaria minor cell
suspension culture. Headspace Solid-Phase Microextraction (HS-SPME) method was used to absorb volatile compounds
from suspension cells and liquid medium. They were then analyzed through Gas Chromatography-Mass Spectrometry
(GC-MS) to identify sesquiterpene compounds. Among the 15 sesquiterpene compounds identified, α- muurolene was found
in significantly higher concentration in all MeJA treated cultures. The results showed that α-muurolene was detected in
the suspension cells at the highest peak area of 14.17% at 100 μM MeJA treated cultures with 3-day incubation. Analysis
of liquid medium of the treatments identified secretion of α-muurolene into the culture medium, with total peak area of
0.72%. These results showed that sesquiterpene production in MeJA induced P. minor suspension culture depended on
the MeJA concentration and also culture incubation period.
In vivo stability of biomaterial-based bone scaffolds often present a significant drawback in the development of materials
for tissue engineering purpose. Previously developed nanobiocomposite bone scaffold using alginate and nano cockle shell
powder has shown ideal characteristics. However, it showed high degradation rate and reduced stability in an in vivo
setting. In this study, we aim to observe the effect of cross-linking glutaraldehyde (GA) in three different concentrations
of 0.5%, 1% and 2% during the fabrication process as a potential factor in increasing scaffold stability. Microstructure
observations of scaffolds using scanning electron microscope (SEM) showed all scaffolds crossed linked with GA and
control had an ideal pore size ranging from 166.8-203.5 µm. Increase in porosity compared to the control scaffolds
was observed in scaffolds cross-linked with 2% GA which also presented better structural integrity as scored through
semi-quantitative methods. Tested pH values during the degradation period showed that scaffolds from all groups
remained within the range of 7.73-8.76. In vitro studies using osteoblast showed no significant changes in cell viability
but a significant increase in ALP enzyme levels in scaffold cross-linked with 2% GA. The calcium content released from
all scaffold showed significant differences within and between the groups. It can be concluded that the use of GA in the
preparation stage of the scaffold did not affect the growth and proliferation of osteoblast and use of 2% GA showed
improved scaffold structural integrity and porosity.
Microbial fuel cells (MFCs) have a high potential application for simultaneous wastewater treatment and electricity
generation. However, the choice of the electrode material and its design is critical and directly affect their performance.
As an electrode of MFCs, the anode material with surface modifications is an attractive strategy to improve the power
output. In this study, stainless steel (SS) and carbon steel (CS) was chosen as a metal anode, while graphite felt (GF)
was used as a common anode. Heat treatment was performed to convert SS, CS and GF into efficient anodes for MFCs.
The maximum current density and power density of the MFC-SS were achieved up till 762.14 mA/m2
and 827.25 mW/m2
,
respectively, which were higher than MFC-CS (641.95 mA/m2
and 260.14 mW/m2
) and MFC-GF (728.30 mA/m2
and 307.89
mW/m2
). Electrochemical impedance spectroscopy of MFC-SS showed better catalytic activity compared to MFC-CS and
MFC-GF anode, also supported by cyclic voltammetry test.
MeSH terms: Bioelectric Energy Sources; Carbon; Electricity; Electrodes; Graphite; Hot Temperature; Metals; Stainless Steel; Steel; Physical Phenomena; Dielectric Spectroscopy; Waste Water
Coronary artery disease (CAD) predominantly manifests in older population above the age of 60 years old. The incidence
of CAD in younger individuals has been reported and is called premature CAD (pCAD). The prevalence for pCAD in
individuals below 45 years old is about 3-10% worldwide. Advances in risk prediction are of great importance as
absolute values of risk factors sometimes correlate poorly with individuals. The measurement of traditional risk factors
such as cholesterol level and blood pressure might be inadequate to predict risk for pCAD and therefore new biomarkers
are required. The introduction of omics technology offers insight into the mechanism and interactions involved during
disease progression and open the possibilities of discovering new biomarkers. Currently, new potential biomarkers for
pCAD have been explored such as homocysteine, apolipoproteins, microRNAs and single nucleotide polymorphisms. In
this review, we discussed the associated risk factors for pCAD, several reported and newly proposed biomarkers and
their potential to be used clinically.
A comparative analysis of metabolites from different parts of Curcuma aeruginosa, i.e. leaves, stems, adventitious
roots and rhizomes was performed by GC-MS/MS coupled with multivariate statistical analysis. The GC-MS/MS analysis
confirmed the occurrence of 26 metabolites belonged to terpenoids in almost all the samples. The Principal Component
Analysis (PCA) indicated that there was a clear distinction between rhizomes and other plant parts, i.e. stems, leaves,
and adventitious roots that could be explained by relatively higher contents of terpenoids including curzerene, alphafarnesen, furanocoumarin, velleral, germacrone cineole, borneol, beta- and gamma- elemene and methenolone. The
results of Hierarchical Clustering Analyses (HCA) corresponded with the PCA results where many terpenoids found
abundantly high in rhizome were clustered together. This was supported by the Pearson correlation analysis that
showed a significantly good relationship between those terpenoids. The adventitious roots demonstrated the strongest
antioxidant activity as compared to the other plant parts which could be attributed to its highest Total Phenolic
Contents (TPC). Total phenolic contents of all the plant parts were positively correlated with their antioxidant activities
which indicate that phenolic compounds may play a role in the overall antioxidant activities of the plants. The results
of the study highlighted the potential of this underexploited Curcuma species which could serve as a new source of
important phytochemicals and natural antioxidant that could be incorporated in functional foods and nutraceuticals.
In addition, chemical and biological evidence shown in the present work has rationalised the different uses of various
plant parts of C. aeruginosa.
Slow lorises (Nycticebus) consist of eight species native to Southeast Asia while three species are recognised in
Malaysia - N. coucang, N. menagensis and N. kayan. This study reports on the rediscovery of the subspecies N. coucang
insularis Robinson, 1917 in Tioman Island and the genetic assessment of its mitochondrial DNA variation. Morphological
measurements conform the specimen as the putative N. coucang but with distinct colour and markings. Two mitochondrial
DNA segments (cytochrome b and control region) were produced from the subspecies representing their first registered
sequences in GenBank. Genetically, the subspecies showed 99% of nucleotide similarity to N. coucang species type for
both the DNA segments and constitute its own unique haplotype. Phylogenetic trees constructed using three methods
(neighbour joining, maximum likelihood and Bayesian inference) showed two major groups within Nycticebus; the
basal group was formed by N. pygmaeus while the second group consisted of the remaining Nycticebus species. The
phylogenetic position of the subspecies, however, remains unresolved due to the observed mixing between N. coucang and
N. bengalensis. Several reasons could lead to this condition including the lack of well documented voucher specimens and
the short DNA fragments used. In addition, the possibility of hybridisation event between N. coucang and N. bengalensis
could not be excluded as a possible explanation since both species occur sympatrically at the Isthmus of Kra region
until the Thailand-Malaysia border. The rediscovery of this subspecies displays the unique faunal diversity that justifies
the importance of Tioman Island as a protected area.
Endophytic fungi are those living inside the host plant without causing any apparent negative effect on the host plant. Two
isolates endophytic fungi from leaves and two isolates from root at Universiti Teknologi MARA (UiTM) Reserve Forest,
Negeri Sembilan were successfully isolated and identified by morphology and molecular characteristic. Samples were
surface sterilized and sub-cultured to obtain a pure culture. Characteristics of the isolates such as colony appearance,
mycelial texture, conidia/spores and pigmentation were studied to explore their morphology. Isolates were also subjected to
a PCR-based genotyping test. There were noticeable differences in morphological characteristics among the four isolates.
Microscopic analysis showed four isolates consist of septa and conidia/spores. The pigmentation result showed that
colony in A1leaf samples demonstrated an orange color on potato dextrose agar (PDA) media, colony in A1root demonstrate
a black texture in PDA media while hairy colonies in the others two isolates showed a white color on PDA media. Based on
molecular analyses the fungal genera showed 99-100% similarity with the related fungi recorded in the GenBank. Both
morphology and molecular sequencing of internal transcribed spacer (ITS) regions of endophytic fungi showed that three
isolates (A1root, C2leaf, and C3root) were grouped in Basidiomycota while one isolate (A1leaf) belonged to Ascomycota. The
endophyte funguses were identified as Daldinia sp. (A1leaf), Polyporales sp. (A1root,) Lentinus sp. (C2leaf,) and Rigidoporus
sp. (C3root). Overall, the new discoveries of isolated endophyte fungal have dyeing potential of fungal pigments which
offer a viable alternative to natural vegetable and harmful synthetic dyes.
Gymnothorax minor is a moray eel of the family Muraenidae found in the Western Pacific Ocean. We report here
its complete mitogenome as determined by Illumina next-generation sequencing and the phylogenetic relationship
with its congeners and other taxa of the family Muraenidae. The whole mitogenome of G. minor had a total length
of 16,574 bp, comprising 37 genes - 13 protein-coding genes (PCGs), two ribosomal ribonucleic acid (rRNA) and 22
transfer ribonucleic acid (tRNA) genes - and a control region. Excepting cox1 with GTG, the other 12 PCGs had ATG
start codon. Seven of its PCGs had incomplete stop codon - five (nad2; cox1; cox2; nad3 and nad4) with T and two
(atp6 and cox3) with TA. Molecular phylogeny based on 13 PCGs was concordant with 15 mitochondrial genes (13 PCGs
and 2 rRNA genes). The subfamily Muraeninae as well as the subfamily Uropterygiinae were monophyletic. However,
the genus Gymnothorax was paraphyletic, with G. minor forming a sister group with Rhinomuraena quaesita in the
lineage containing also G. kidako and G. formosus forming a sister group with Enchelynassa canina. The phylogenetic
relationship of the genus Gymnothorax and related taxa of the family Muraenidae, based on the mitochondrial cob
gene, was in general similar to that based on 15 mt-genes. The mitogenome is useful for future studies on phylogenetics
and systematics of eels of the family Muraenidae and other taxa of the order Anguilliformes.
Aryl diazonium salts are coupling agents that assist in molecules attachment to interfaces for sensing purposes. Despite
not being fully explored and not yet widely applicable for cell-based sensors, the high stability of aryl diazonium salt
formed sensing system is highly favorable in biological applications. Carbon-based electrodes are the most commonly
used in aryl diazonium modification due to its post grafting stable C-C bond formation. Here, salt bridge based microbial
fuel cells (MFCs) were used to study on the effect of aryl diazonium modification on the anode graphite fibre brush. Aryl
diazonium salts were in situ generated by the diazonation of p-phenylenediamine with NaNO2 in HCl solution. The
electrochemical performance of the aryl diazonium modified graphite brush MFC was measured and compared with the
unmodified graphite brush MFC. The power output of the modified graphite brush bioanode was higher (8.33 W/m3
)
than the unmodified graphite brush (7.60 W/m3
) after 20 days of operation with ferricyanide as the catholyte. After 70
days of operation using phosphate buffer solution as the catholyte, the Pmax of modified brush was three times higher
(0.06 W/m3
) than of the unmodified brush (0.02 W/m3
), which indicates an enhanced binding towards the substrate that
facilitates a better electron transfer between the microbial and electrode surface.
Adequate development of uterine receptivity is crucial for establishment of pregnancy. Expression of uterine receptivity
molecules i.e. αvβ3 integrin, E-cadherin and mucin-1 could be affected by testosterone. The objective of this study was
to investigate effect of testosterone on expression of these molecules during early pregnancy. 30 ovariectomised female
Sprague-Dawley rats were divided into 5 groups that consisted of vehicle control, rats received eight days sex-steroid
replacement regime (intended to mimic the hormonal changes in early pregnancy) and three groups of rats given
testosterone (1 mg/kg/day) subcutaneously with or without flutamide or finasteride between day 6 and 8 representing the
period of uterine receptivity. At the end of the treatment, rats were sacrificed and uteri were removed. Expression and
distribution of αvβ3 integrin, E-cadherin and mucin-1 were examined by immunoflourescence and levels of messenger
RNA (mRNAs) were evaluated by real-time PCR. Expression of αvβ3 integrin, E-cadherin and mucin-1 in the uteri of
rats receiving sex-steroid replacement regime increased significantly as compared to control (p<0.05). In these rats,
concomitant administration of testosterone between day 6 and 8 resulted in expression of αvβ3 integrin, E-cadherin
and mucin-1 to decrease significantly (p<0.05) as compared to rats receiving sex-steroid replacement regime without
testosterone treatment. Moreover, the testosterone effects were not antagonized by either flutamide or finasteride. As
a result, reduced expression of uterine receptivity molecules by testosterone might interfere with early pregnancy
establishment, therefore could adversely affect the female fertility.
Neurological diseases are one of the serious health hazards faced by mankind for decades. Neurite outgrowth is a key
factor responsible for proper neuronal development. Any misplacement in the process could lead to neurological diseases
like Alzheimer’s and Parkinson’s. Treatment with the available synthetic drugs imparts many difficulties to the patients
due to the side effects. Compounds from natural sources can be considered as an effective replacement for this. Mucuna
pruriens, used in traditional ayurvedic medicine, contains L-3,4-dihydroxy phenylalanine (L-DOPA) in its seeds, which
possesses medicinal effects against neurological diseases. In this regard, seed extracts of M. pruriens originated from
Thailand and India, were analyzed for their neuroprotective effects in Neuro2a cells. Hexane, ethyl acetate and ethanol
extracts were found to be non-toxic to the viability of the cells. Ethanol extracts of M. pruriens of Thai origin (MTE),
hexane extracts of M. pruriens of Indian origin (MIH) and ethyl acetate extracts of M. pruriens of Indian origin (MIEA)
were able to induce neurite outgrowth in Neuro2a cells. Interestingly, both MTE and MIH induced neurite outgrowth
dependent on Teneurin-4 (Ten-4) transmembrane protein whereas MIEA did the same independent of Ten-4, which was
confirmed by real time PCR and gene silencing approach. The present study suggested that M. pruriens can be used as
a potential drug in the treatment of neurological diseases as it can induce neurite outgrowth by multiple mechanisms,
which will be of great use in the field of medicine.
Fructose is commonly used as a taste enhancer in many processed foods. Excessive fructose consumption is highly
associated with obesity and development of cancer particularly prostate cancer. This study aimed to investigate the
biochemical and molecular changes in the prostate tissue of rats treated with 20% fructose for six months. A total
of 18 rats weighted 200-250 g were divided into two groups, where each group consisted of 9 rats. Control group
is given normal diet, while the treated group was given normal diet and 20% fructose in drinking water. After six
months of treatment, both groups were sacrificed for further analysis. Body weight, blood pressure and glucose were
measured. Lipid profiles were determined using quantitative colorimetric assay. Transcripts level of 11β-hydroxysteroid
dehydrogenase type 1 (11β-HSD1), leptin (LEP), angiopoietin 1 (ANGPT1), microRNA (miR)-34a, miR-10b and miR192 were determined using quantitative PCR, while the protein levels of 11β-HSD1 and leptin were determined using
ELISA. The results showed that 20% fructose diet significantly increased blood glucose level as compared to the control
(p<0.05). The transcript levels of LEP and miR-192 were significantly lower in the fructose-treated group as compared
to the control (p<0.05). There was a significant linear relationship between prostate LEP and serum LDL/VLDL level
as well as between the level of prostate LEP and serum total cholesterol level (p<0.05). Thus, our results showed that
chronic consumption of fructose could down-regulate LEP and miR-192 expression in prostate tissue, and promote
higher accumulation of fat in the tissue. Additionally, downregulation of miR-192 has been reported to be associated
with the pathogenesis of prostate cancer. Thus, it can be concluded that long-term fructose diet leads to higher blood
glucose level and down-regulation of LEP and miR-192 expression in prostate tissue.
F-box proteins containing variable C-terminal domains make an essential part of SKP1-Cullin-Ring box-F box (SCF)
complex. SCF complex catalyzes the final step to link the ubiquitin tag with the target protein, destined for degradation,
through F-box protein that confer overall substrate specificity to the complex. In this study, we analyzed the role of
At2g02870, a Kelch containing F-box protein from Arabidopsis thaliana, by using reverse genetics strategy. At2g02870
loss of function mutant lines (at2g02870) were analyzed and compared with wild type plants for the expression of genes
and products of hydroperoxide lyase (HPL) branch of oxylipin pathway. We found that the at2g02870 plants have enhanced
expression of HPL pathway genes and produce more green leaf volatiles (GLV) than the wild type plants. Our results
suggested that the gene is involved in the regulation of HPL pathway, possibly through the degradation of enzymes or/
and the regulatory factors of the pathway.
The aim of this study to determine the numbers of CD34+ cells and total nucleated cell (TNC) in umbilical cord blood (UCB)
collected from pregnant mothers with gestational diabetes mellitus (GDM) and preeclampsia (PE), following statistical
analysis of both maternal and perinatal factors which affect UCB parameters. Most of studies explored the influence of
obstetric factors on the number of UCB cell collection and only a few looked at the effects on UCB haematopoietic stem
cell (UCB-HSC) of common disorders complicating pregnancy. A total of 112 UCB samples (32 PE, 42 GDM and 38 nondiseased) were collected. CD34+ cell and NC count were enumerated using FACS Calibur. The TNC and CD34+ cells were
significantly reduced in both PE and GDM groups as compared to the control group. The PE group shows significantly
lower birth weight and higher BP which led to a lower UCB volume and CD34+ count. Gestational age shows significant
correlation with nucleated cell count (NCC) and TNC. GDM group shows significantly lower systolic BP, NCC and TNC count,
including low placental weight and birth weight. Conclusively, some obstetrics factors have significant influences to the
numbers and quality of UCB-HSC in both PE and GDM groups, which could guide in the selection criteria for CB banking.