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Study of Glutinous and Non-Glutinous Rice
(Oryza Sativa) Varieties on Their Antioxidant
Compounds
Widiastuti Setyaningsih, Nikmatul Hidayah, Irfan Estiono Saputro, Miguel Palma Lovillo,
and Carmelo García Barroso
Abstract—Cultivated rice (Oryza sativa) is a global cereal crop
in Southeast Asia. It serves as staple food, thus has a major contribution to the calorie intake. Furthermore, a number of antioxidant substances have been identified in rice including phenolic compounds and melatonin. The concentration and composition of these antioxidant compounds were studied on glutinous and non-
glutinous grains for both pigmented and non-pigmented rice varieties. Additionally, several medium-amylose rice grains of three Indonesian varieties (IR64, umbul-umbul and pandan wangi) were also evaluated. Finding indicates that the composition of phenolic compounds are noticeably different between glutinous and non-glutinous rice grains. The level of both melatonin and total phenolics in non-glutinous rice was higher than its glutinous variety. Hence, higher amylose content exhibits relatively higher amount of antioxidant compounds.
Keywords—Rice, amylose, glutinous, antioxidants
I.INTRODUCTION
ICE (Oryza sativa) is a pivotal cereal crop as subsists
calories for Southeast Asian livelihoods. This grain is
remarkably essential for the nutrition status of a large
number of the population within this region. In addition to
nutrition purposes, rice contains secondary metabolites that are possessing several antioxidant compounds namely
melatonin [1] and phenolic compounds [2]. These compounds
attracted a growing attention in recent years due to their health
benefits, as their consumption has been linked to lowering the
risk of diseases related with oxidative stress i.e. inhibitory
effects on carcinogenesis and mutagenesis [3], [4]. Recent
research has led to an increase in the production of antioxidant
compounds in transgenic rice seeds and antioxidant-rich rice plants have been successfully generated. Functional rice
products have also become more widely appreciated in the
current market.
Widiastuti Setyaningsih, is with Department of Analytical Chemistry,
Faculty of Sciences, University of Cadiz, Puerto Real, Spain. Department of
Food and Agricultural Product Technology, Gadjah Mada University,
Yogyakarta, Indonesia. Email: widiastuti.setyaningsih@uca.es,
widiastuti.setyaningsih@ugm.ac.id.
Nikmatul Hidayah, is with Indonesian Center of Agricultural Postharvest
Research and Development, Bogor, Indonesia.
Irfan Estiono Saputro, Miguel Palma Lovillo, and Carmelo García Barroso,
are with Department of Analytical Chemistry, Faculty of Science, University
of Cadiz, Puerto Real, Spain.
Email: nikmatul.hidayah@litbang.deptan.go.id, irfan.estiono@alum.uca.es,
miguel.palma@uca.es, carmelo.garcia@uca.es
The phenolics compounds described in rice grains are
phenolic acids [5] and its aldehydes [6]. The most common
forms of phenolic acids in rice are derived from
hydroxybenzoic (C6−C1; an aromatic ring linked to a carbon
atom) and hydroxycinnamic (C6−C3; an aromatic ring linked
to a three-carbon chain) acids. Along with these two major
groups, aldehyde analogues such as protocatechuicaldehyde, p-hydroxybenzaldehyde [7] and vanillin [6], were also found
in rice grains.
As well as phenolic compounds, the presence of melatonin
[N-acetyl-3-(2-aminoethyl)-5-methoxyindole] in rice grain has
been identified in a wide range of varieties [8]. However, both
the level and composition of these compounds in different
varieties of rice grains may diverge in phenolics and melatonin
concentrations. This discrepancy reveals that one would also expect changes due to the differences on their type of starch
that have been distinguished as glutinous (waxy) and non-
glutinous variety.
Glutinous differs from the regular (non-glutinous) rice
mainly in having low (<5%) or almost no amylose in its starch
but basically high in amylopectin [9]. Amylose is essentially
long linear chains composed of (1→4)-linked α-D-
glucopyranosyl units with a few (1→6)-α-linkages branches whilst amylopectin has a higher molecular weight and much
shorter chains of (1→4)-linked α-D-glucose units that are
highly branched through additional (1→6)-α-linkages (Fig. 1).
In general, the amylose content of rice starch varies from 0-
2% in waxy (glutinous), 20-25% in normal or medium and up
to 30% in high-amylose rice grains.
It has been reported higher production of antioxidant
compounds from high-amylose genotypes versus the waxy (glutinous) ones for corn (Zea mays L.) grains [10], further
work will be necessary to study the level and composition of
antioxidants compounds in other foods, including rice. Hence,
the objective of the study described here was to assess the
levels of antioxidant compounds, including melatonin and
phenolics on some rice varieties taking into account their
amylose content.
R
International Conference on Plant, Marine and Environmental Sciences (PMES-2015) Jan. 1-2, 2015 Kuala Lumpur (Malaysia)
http://dx.doi.org/10.15242/IICBE.C0115068 27
Fig. 1 Molecular representation of amylose and amylopectin.
II. MATERIALS AND METHODS
A. Materials and Chemicals
HPLC-grade methanol (MeOH), acetic acid, and ethyl acetate (EtOAc) were purchased from Merck (Darmstadt,
Germany). Melatonin (MEL) standard, M-5250, was obtained
from Sigma-Aldrich (St. Louis, MO, USA). Water was
purified with a Milli-Q purification system (Millipore,
Billerica, MA, USA). Phenolic compound standards of the
highest available purity were used. Protocatechuic acid (PRO),
protocatechuic aldehyde (PRA), vanillic acid (VAA), p-
hydroxybenzoic acid (p-HBA), vanillin (VAN), p-
hydroxybenzaldehyde (p-HB), ferulic acid (FER) and
sinapic acid (SIN) were obtained from Fluka (Buchs, Switzerland). Guaiacol (GUA), p-Coumaric acid (p-COU),
caffeic acid (CAF), chlorogenic acid (CHL), 5-
hydroxymethyl-2-furaldehyde (HMF), and 5-methylfurfural
(MF) were obtained from Sigma–Aldrich (St. Louis, MO,
USA). Ellagic acid (ELL) and iso-vanillic acid (IVA) were
purchased from Sarsynthese (Merignac, France).
B. Rice Samples
Rice samples including non-pigmented and black
pigmented of both glutinous and non-glutinous rice grains
were obtained from an Asian market in Spain. Three varieties
of Indonesian medium-amylose rice produced using
conventional farming systems were obtained randomly from
various smallholder rice mills in Central Java area (umbul-
umbul, pandan wangi and IR64).
C. Sample Preparation
A rice sample (20 g) was placed in a plastic cylinder and
rice grains were milled with an Ultraturrax homogenizer
(IKA® T25 Digital, Germany) for 10 min prior to extraction.
The milling process was stopped every 1 min to avoid excessive heating of the sample. The fine grain was then
homogenized by stirring and then stored in a closed labelled
bottle.
D. Extraction Technique
Phenolic compounds and melatonin extractions were
performed in a Dionex ASE 200 extractor (Dionex,
Sunnyvale, CA, USA) equipped with incorporating stainless
steel extraction cells (11 mL volume) and collection vials (60
mL capacity). A cellulose filter was inserted at the outlet end
of the extraction cell.
An accurately weighed sample of rice powder (2.5 g) and
washed sea sand were loaded into the extraction cell. The Pressurized Liquid Extraction (PLE) condition for phenolic
extractions was 60% (v/v) EtOAc in MeOH, static time of 10
min in 3 cycles at 190 ºC under a pressure of 200atm, flushing
100% and purge for 60 s; while for melatonin extraction was
70% (v/v) EtOAc in MeOH, static time of 5 min in 2 cycles at
200 ºC under a pressure of 200atm, flushing 50% and purge
for 60 s. The resulting extract was dried under vacuum on a
rotary evaporator. The residue was reconstituted with methanol and adjusted to a final volume of 5 mL. The liquid
was then passed through a 0.45 µm nylon filter prior to
injection on the HPLC-FD system.
E. Determination of Phenolic Compounds
High performance liquid chromatography (HPLC)
analyses were carried out on Dionex HPLC system comprised
a Dionex P680 HPLC Pump, Dionex ASI 100 Automated
Sample Injector, Dionex PDA-100 Photodiode Array
Detector, Dionex UCI-50 Universal Chromatography
Interface, and Dionex TCC-100 Thermostatic Column
Compartment. Separations were performed on a reversed
phase RP 18 Lichrospher Column (LiChroCART 250 × 4 (5μm) Merck KgaA). Gradient elution was carried out at a
flow rate of 1.0 mL min–1. A PDA-100 Photodiode Array
Detector was used for UV-Vis and the 3D mode was set at
collection rate of 1.0 Hz, 3D wavelength scan range 250-600
nm, 3D bunch width 1 nm and band width 50 nm. The column
compartment thermostat was set at 25oC. Injection volume
was set to 25 μL.
A gradient elution program was used with two mobile
phases: A (2% acetic acid and 5% MeOH in water) and B (2%
acetic acid and 88% MeOH in water). The mobile phases were
filtered through a 0.45 µm membrane filter (Millipore) and were degassed for 15 min prior to use. The gradient applied
was as follows: (time, solvent B): 0 min, 0%; 10 min, 25%; 25
min, 40%; 30 min, 50%; 35 min, 50%. The identification of
phenolic acids in the samples was achieved by spiking and by
comparison of retention times and maximum UV-Vis
absorptions with those of standards.
F. Determination of Melatonin
Chromatographic separations were carried out on an
Alliance HPLC 2695 system, controlled by an Empower Pro
2002 data station (Waters, Milford, MA) and coupled with a
fluorescence detector (Waters 474 Fluorescence Detector).
The column separation and mobile phase preparation were
similar with phenolics determination. The applied gradient was as follows: (time, solvent B): 0 min, 0%; 5 min, 35%; 12
min, 40%; 15 min, 40%; 20 min, 45%; 25 min, 50%. The
established conditions for fluorescence detector were as
follows: excitation wavelength was set at 290 nm, emission
wavelength was set at 330 nm, sensitivity was set at gain
1000, attenuation was fixed at 16, and injection volume was
set to 10 µL.
International Conference on Plant, Marine and Environmental Sciences (PMES-2015) Jan. 1-2, 2015 Kuala Lumpur (Malaysia)
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G. Determination of Amylose Content
Amylose content of the samples was determined by
Iodometric method based on official methods of analysis of
AOAC. In summary, 100 mg of sample were weighed and
mixed with 1 mL 95% ethanol and 9 mL of 1N NaOH. The
samples were diluted and the iodine solution was added. After
10 min incubation at room temperature, the absorbance at 625
nm was analysed with a spectrophotometer and the amylose
content was calculated based on the standard curve. The
samples were analysed in triplicate.
H. Performance of the Method
The analytical procedures for the chromatographic methods
for melatonin and phenolic compounds were carried out
according to the recommendations of ICH Guideline Q2 (R1)
and suggestions in ISO 17025. Linearity, range, precision, detection and quantification limits of the method were
established. Linearity was evaluated in order to express the
ability of the method to obtain test results that are directly
proportional to the concentration of melatonin in two different
ranges. Appropriate dilution from a stock solution of
melatonin was carried out to give concentrations ranging from
0.75 to 15 µg L–1 and 15 to 750 µg L–1. A series of dilution
from stock solution of phenolic compounds was carried out to give concentrations from 0.15 to 12 mg L-1. Gnumeric 1.12.17
was used to generate the regression analysis. Calibration
curves were obtained from these regression analyses and the
melatonin and phenolic compounds in the extracts were
quantified. The standard deviation (σ) obtained for the
response and the slope (a) from the regression were then used
to calculate the limit of detection (LOD) and limit of
quantification (LOQ).
The precision of the method was evaluated by performing
repeatability (intra-day) and intermediate precision (extra-
day). Repeatability was assessed by ten independent analyses
of the same samples on the same day while intermediate
precision was determined by five independent analyses on
three consecutive days. Precision was expressed as coefficient of variance (CV) of retention time and peak signal. The CV
values for both repeatability and intermediate precision were
less than 6% showing that the methods have adequate
precisions.
The analytical properties for the determination of phenolic
compounds and melatonin are listed in Table I.
I. Data Analysis
The experimental results in single- and two-factor
experiments were analysed using Gnumeric. The Analysis of
Variance (ANOVA) and Least Significant Difference (LSD)
test were used to determine the significant differences (p <
0.05) between the means.
III. RESULT AND DISCUSSION
A. Phenolics in Glutinous and Non-glutinous Rice
In order to evaluate the phenolic levels and compositions on
glutinous and non-glutinous rice, two clusters of rice varieties
i.e. non-pigmented and black pigmented rice grains were
extracted and analysed in duplicate (Table II). Result shows that the content of phenolic compounds in rice samples with
higher amylose content (non-glutinous) were higher than in
the glutinous samples for both clusters. The highest
concentration of phenolics presented in pigmented-rice was
211.94±18.65 µg g-1 owned by black non-glutinous rice then
followed by its glutinous type (209.00±18.39 µg g-1).
TABLE I. ANALYTICAL CHARACTERISTICS FOR THE DETERMINATION OF MELATONIN AND PHENOLIC COMPOUNDS
Compounds Concentration
range Linear equation R
2 LOD LOQ
Intra-day, CV (%)
n = 10
Inter-day, CV (%),
n = 3 × 5
RT Peak RT Peak
PRO 0.15 – 12* y = 1.32x − 0.05 0.9997 0.23
* 0.77
* 0.00 0.33 0.26 2.33
PRA 0.15 – 12* y = 5.52x + 0.03 0.9999 0.17
* 0.56
* 0.00 0.33 0.21 2.22
p-HBA 0.15 – 12* y = 7.43x − 0.23 0.9997 0.22
* 0.74
* 0.00 0.38 0.21 2.22
p-HB 0.15 – 12* y = 3.44x − 0.07 0.9998 0.23
* 0.75
* 0.00 0.49 0.18 1.85
VAA 0.15 – 12* y = 1.34x + 0.06 0.9996 0.26
* 0.87
* 0.08 0.32 0.10 0.45
IVA 0.15 – 12* y = 1.37x + 0.08 0.9994 0.32
* 1.07
* 0.07 0.24 0.06 0.23
VAN 0.15 – 12* y = 1.85x − 0.02 0.9998 0.20
* 0.67
* 0.00 0.48 0.22 1.83
GUA 0.15 – 12* y = 0.35x + 0.03 0.9993 0.37
* 1.24
* 0.00 1.43 0.24 0.71
p-COU 0.15 – 12* y = 7.52x + 0.16 0.9998 0.18
* 0.61
* 0.04 0.36 0.16 2.19
FER 0.15 – 12* y = 4.96x − 0.27 0.9996 0.27
* 0.90
* 0.04 0.65 0.14 2.10
CAF 0.15 – 12* y = 3.74x – 1.05 0.9963 0.84
* 2.80
* 0.05 0.40 0.06 0.63
CHL 0.15 – 12* y = 10.56x – 3.85 0.9916 1.27
* 4.23
* 0.06 5.99 0.11 3.33
SIN 0.15 – 12* y = 4.72x – 0.29 0.9996 0.27
* 0.90
* 0.04 0.45 0.14 1.65
HMF 0.15 – 12* y = 24.87x – 1.95 0.9998 0.18
* 0.61
* 0.16 0.17 0.21 0.60
MF 0.15 – 12* y = 0.32x + 0.28 0.9954 0.94
* 3.12
* 0.06 0.42 0.48 1.36
ELL 0.15 – 10* y = 1.35x + 0.12 0.9827 1.59
* 4.83
* 0.05 3.32 0.15 5.49
Melatonin 0.75 to 15**
y = 580.79x – 1806.8 0.9957 1.15**
3.84**
0.99 0.93 1.23 2.05
15 to 750**
y = 615.11x − 961.13 0.9994 * Range in the unit of mg/Kg
-1
** Range in the unit of µg/Kg
-1
International Conference on Plant, Marine and Environmental Sciences (PMES-2015) Jan. 1-2, 2015 Kuala Lumpur (Malaysia)
http://dx.doi.org/10.15242/IICBE.C0115068 29
The difference of phenolics content between black
glutinous and black non-glutinous rice was not as impressive
as if compared to the non-pigmented rice. Thus, in this
particular case, phenolics concentration in rice appears to be strongly related to the pigment of rice in their bran. Both
black pigmented glutinous and non-glutinous rice grains were
produced without a bran removal process called polishing.
Hence, as the phenolic compounds are mainly associated with
the pericarp in the grain, the milling process to produce
polished grain reduces the level of these compounds in the
grain.
In contrary, the levels of phenolics in non-pigmented (polished) grains were prominently remarkable for different
amylose content: 35.58±3.13 µg g-1 for non-glutinous rice
whilst 16.15±1.42 µg g-1 for glutinous rice. The level of
phenolics in non-glutinous was roughly two folds higher than
its glutinous type. This finding agrees the result revealed by
Chi et al. [11] who conducted a research related to phenolics
analysis of Korean rice grain varieties. These researchers
confirmed that polished non-glutinous rice (Ilpumbye) extract
has a higher level of phenolics than the glutinous type (Hwasunchalbyo).
B. Melatonin in Glutinous and Non-glutinous Rice
The level of melatonin in rice with different amount of
amylose content was studied on the same sample used in
previous experiment of phenolics. However, unlike the result for phenolics, the difference in melatonin contents between
black glutinous (182.04±2.79 µg Kg–1) and non-glutinous rice
(73.81±1.13µg Kg–1) was notably more significant. The level
of melatonin in black non-glutinous rice was more than
double than in its glutinous type.
This variation is reasonable when taking into consideration
the specific type of carbohydrates in rice support the synthesis
of the neurotransmitter serotonin, which is later transformed into melatonin [12]. Thus, the presence of lower amounts of
starch may not enhance the synthesis of melatonin.
C. Phenolics and Melatonin in Medium-Amylose Rice
Three rice varieties from conventional farming were used
in this study. In addition to being considered as aromatic rice,
together with umbul-umbul, pandan wangi represents the local
rice varieties of Indonesia. IR64 is a rice variety that was
developed in a major advance in rice production as it provided
higher yield potential, greater yield stability and more
efficient management practices. Amylose content in these
tested rice varieties was determined (Fig. 2). Subsequently, in order to study the effect of amylose content on the level of
antioxidant compounds including phenolic and melatonin, a
single-factor ANOVA has been used (p.0.05). ANOVA
revealed that the amylose content has significant effect on the
level of antioxidant compounds for both phenolics and
melatonin. It is, therefore, Least Significant Differences
(LSDs) for these factors were also estimated (Fig. 2).
The levels of both phenolics and melatonin for the three tested varieties were directly corresponded to the amount of
amylose content wherein the higher the amylose content, the
higher the amount of antioxidant compounds. This finding is
consistent with that reported by Li et al.[10], who found that
plant samples with high amylose contents exhibit better
antioxidant activity than their glutinous genotypes. Despite
significant research effort, the specific antioxidant enhanced
by amylose has not been investigated further and phenolics as well as melatonin are considered as a potential molecule that
has a high antioxidant activity [13].
IV. CONCLUSION
Antioxidant compounds in glutinous and non-glutinous rice
were studied. The results suggest a positive correlation
between the amylose content and the level of antioxidant
compounds i.e. melatonin and phenolic compounds. However,
particularly in pigmented variety, rice bran contributes greater effect on the level of phenolics in rice grain than the amylose
content.
TABLE II. PHENOLIC COMPOUNDS IN TESTED SAMPLES
Cluster Rice Sample (Amylose Level)
Picture
MEL (µg
Kg-1
)
Phenolic compounds (mg Kg-1
)*
PRO PRA p-HBA p-HB VAA IVA VAN GUA p-COU FER CAF CHL SIN ELL HMF MF SUM
Pigmented
Rice
Black
Non-glutinous (Medium Amylose
Content)
182.04±2.79
74.58±1.97
7.16± 0.20
2.81± 0.12
0.49± 0.01
59.56± 6.94
1.04± 0.16
2.79± 0.07
45.00± 2.67
1.38± 0.04
5.71± 0.34
2.53± 0.13
0.85± 0.05
0.48± 0.01
7.40± 0.49
0.16± 0.01
ND 211.94±18.65
Black glutinous (Low Amylose
Content)
73.81±
1.13
91.47
±2.42
6.77±
0.19
3.34±
0.15
1.97±
0.05
34.50±
4.02
1.74±
0.28
1.96±
0.05
29.65±
1.76
4.74±
0.14
5.87±
0.35
1.55±
0.08
0.92±
0.06 ND
24.35±
1.62
0.16±
0.01 ND
209.00
±18.39
Non-
pigmented
Rice
White
Non-glutinous (Medium Amylose
Content)
- 1.65±
0.04
1.13±
0.03
3.64±
0.16
3.47±
0.10 ND ND
1.29±
0.03
10.68±
0.63
0.98±
0.03
2.16±
0.13
0.96±
0.05
0.83±
0.05
0.17±
0.00
6.56±
0.44
0.17±
0.01
1.88±
0.08
35.58±
3.131
White
Glutinous (Low Amylose
Content)
- 0.81±
0.00
0.70±
0.02
1.63±
0.07
4.10±
0.11
0.28±
0.03 ND
0.97±
0.02
3.28±
0.19
0.31±
0.01
1.02±
0.06
0.84±
0.04
0.76±
0.05 ND
1.29±
0.09
0.17±
0.01 ND
16.15±
1.422
* ND: Not Detected (< LOD)
International Conference on Plant, Marine and Environmental Sciences (PMES-2015) Jan. 1-2, 2015 Kuala Lumpur (Malaysia)
http://dx.doi.org/10.15242/IICBE.C0115068 30
Fig. 2 Melatonin (1) and phenolics (2) levels in medium-amylose rice varieties. LSD: bars followed by the same letter are indicated as not
significantly different (p = 0.05) conclusion
Acknowledgment
W. S. thanks the CIMB Foundation for a Ph.D. studentship
through the CIMB Regional Scholarships
.REFERENCES
[1] W. Setyaningsih, M. Palma, C.G. Barroso, "A new microwave-assisted
extraction method for melatonin determination in rice grains," J. Cereal
Sci., vol. 56, pp. 340–346. 2012.
http://dx.doi.org/10.1016/j.jcs.2012.02.012
[2] S. Tian, K. Nakamura, H. Kayahara, "Analysis of Phenolic Compounds
in White Rice , Brown Rice , and Germinated Brown Rice," J. Agric.
Food Chem., vol. 52, pp. 4808–4813. 2004.
http://dx.doi.org/10.1021/jf049446f
[3] S. Yafang, Z. Gan, B. Jinsong, "Total phenolic content and antioxidant
capacity of rice grains with extremely small size," African J. Agric.
Res., vol. 6, pp. 2289–2293. 2011.
[4] R. Sompong, S. Siebenhandl-Ehn, G. Linsberger-Martin, E. Berghofer,
"Physicochemical and antioxidative properties of red and black rice
varieties from Thailand, China and Sri Lanka," Food Chem., vol. 124.
pp. 132–140. 2011. http://dx.doi.org/10.1016/j.foodchem.2010.05.115
[5] M.A. Al-Farsi, C.Y. Lee, "Optimization of phenolics and dietary fibre
extraction from date seeds," Food Chem. vol. 108, pp. 977–985. 2008.
http://dx.doi.org/10.1016/j.foodchem.2007.12.009
[6] Y. Qiu, Q. Liu, T. Beta, "Antioxidant properties of commercial wild
rice and analysis of soluble and insoluble phenolic acids," Food Chem.,
vol. 121, pp. 140–147. 2010.
http://dx.doi.org/10.1016/j.foodchem.2009.12.021
[7] W. Setyaningsih, I.E. Saputro, M. Palma, C.G. Barroso, Optimisation
and validation of the microwave-assisted extraction of phenolic
compounds from rice grains, Food Chem., vol. 169, pp. 141–149.
2015. http://dx.doi.org/10.1016/j.foodchem.2014.07.128
[8] W. Setyaningsih, N. Hidayah, I.E. Saputro, M.P. Lovillo, C.G.
Barroso, "Melatonin Profile during Rice (Oryza Sativa) Production," J.
Adv. Agric. Technol., vol. 1, pp. 60–64. 2014.
[9] H.-J. Chung, Q. Liu, L. Lee, D. Wei, "Relationship between the
structure, physicochemical properties and in vitro digestibility of rice
starches with different amylose contents," Food Hydrocoll., vol. 25, pp.
968–975. 2011. http://dx.doi.org/10.1016/j.foodhyd.2010.09.011
[10] W. Li, C.V. Wei, P.J. White, T. Beta, "High-amylose corn exhibits
better antioxidant activity than typical and waxy genotypes.," J. Agric.
Food Chem., vol. 55, pp. 291–8. 2007.
http://dx.doi.org/10.1021/jf0622432
[11] H.-Y. Chi, C.-H. Lee, K.-H. Kim, S.-L. Kim, I.-M. Chung, "Analysis
of phenolic compounds and antioxidant activity with H4IIE cells of
three different rice grain varieties," Eur. Food Res. Technol., vol. 225,
pp. 887–893. 2007. http://dx.doi.org/10.1007/s00217-006-0498-3
[12] USA Rice® Federation, "Rice Nutrition Information,"
http://www.usarice.com/index.php?option=com_content&view=article
&id=1727&Itemid=660 (accessed September 23, 2014).
[13] I. Gulcin, M.E. Buyukokuroglu, M. Oktay, I. Kufrevioglu, "On the in
vitro antioxidative properties of melatonin," J. Pineal Res.,vol. 33,pp.
167–171. 2002. http://dx.doi.org/10.1034/j.1600-079X.2002.20920.x
Widiastuti Setyaningsih was born in Klaten, Indonesia on July 21, 1984.
She graduated cum laude from Gadjah Mada University (UGM) with a
Bachelor of Food Technology. She received her M.Sc. from Gdansk
University of Technology (GUT) Poland, University of Barcelona (UB) and
University of Cadiz (UCA), Spain under the frame of European Master in
Quality in Analytical Laboratories (EMQAL).
She is a LECTURER at the Department of Food and Agricultural Product
Technology, Faculty of Agricultural Technology, UGM, Indonesia. Presently,
she is pursuing her doctoral studies in field of food analytical chemistry at the
Department of Analytical Chemistry, Faculty of Sciences, UCA, Spain. She
held an undergraduate scholarship from UGM for the period of 2004–2005, an
Erasmus Mundus Scholarship from European Union Commission (Education,
Audiovisual and Culture Executive Agency-EACEA) during the period 2010–
2011, a MAEC-AECID (Agencia Española de Cooperación Internacional para
el Desarrollo) scholarship from the Ministry of Spain for 2011–2012, and a
Ph.D. studentship from the CIMB Foundation from 2012 to date. Her research
is focused on analytical method development and validation for bio-active
compounds in foods.
Nikmatul Hidayah was born in Magelang, Indonesia in February 1982.
She graduated from Gadjah Mada University (UGM) with a bachelor of Food
Technology. At present, she is a RESEARCHER at Indonesian Center of
Agricultural Postharvest Research & Development, Bogor, Indonesia.
Her research is focused on postharvest handling and processing of
agricultural product such as enzymatic processing of rice and modification of
flour based on local agricultural product in Indonesia.
Irfan Estiono Saputro was born in Jakarta, Indonesia on 25 April 1984.
His desire to pursue a career in science was reinforced after opting for Food
Quality Assurance as his major at Bogor Agricultural University (IPB),
Indonesia. In order to advance his knowledge in food analytical chemistry, he
is currently pursuing a European Master in Quality in Analytical Laboratories
(EMQAL) at the University of Barcelona (Spain).
Professor Miguel Palma Lovillo was born in Olvera, Spain on January
14, 1968. He obtained his degree in Chemistry at the University of Cadiz
(UCA) and later obtained his Ph.D. in Science at the same University in 1995.
He is a FULL PROFESSOR of Analytical Chemistry at the Faculty of
Sciences, UCA, Spain. He was visiting scientist at the Department of Pharma-
ceutical Sciences at the Southern School of Pharmacy in Mercer University,
Atlanta, GA, USA and also at the Department of Chemistry, at Virginia Tech,
Blacksburg, VA, USA.
Professor Palma received the Premio Extraordinario de Doctorado (the
Highest Distinction at PhD level) at the Faculty of Sciences (UCA) and the
Premio Extraordinario de Licenciatura “Octavio Comes” (Distinction at
Bachelor degree). His research interests include food analytical methods, food
science, functional foods and bioactive compounds in foods.
Professor Carmelo García Barroso was born in Arcos, Spain on
December 9, 1955. He obtained his degree in Chemistry at the University of
Cadiz (UCA) and then his Ph.D. in Sciences at the same University in 1985.
He is a FULL PROFESSOR of Analytical Chemistry at Faculty of
Sciences, UCA, Spain. His research is focus on food and wine science and
food analytical methods.
Professor García co-founded the Spanish Society for Wine Research
(GIENOL) and was elected President of this Society in 1999. He is
responsible for the postgraduate program in Agrifood Sciences, a common
teaching program between UCA and the University of Cordoba (Spain) since
2006. In 2001 he became Chairman of the Andalusian Center for Wine
Research, a research center at UCA sponsored by the local Andalusian
Government.
International Conference on Plant, Marine and Environmental Sciences (PMES-2015) Jan. 1-2, 2015 Kuala Lumpur (Malaysia)
http://dx.doi.org/10.15242/IICBE.C0115068 31
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