This study aims to determine the antioxidant capacities (AC) and antidiabetic properties of
phenolic extracts (free and bound) from white Tambun pomelo peels, kaffir lime peels, lime
peels and calamansi peels. AC, total phenolic content (TPC) and antidiabetic properties of
selected citrus peels extracts were determined spectrophotometrically using 2,2-Diphenyl-1-
picrylhydrazyl free radical (DPPH) scavenging, ferric-reducing antioxidant power (FRAP),
Folin-Ciocalteu (FC) and α-amylase and α-glucosidase inhibition assay, respectively. This
study found that the methanolic extract of kaffir lime showed the best AC with the lowest
IC50 value of DPPH radical (7.51 ± 0.50 mg/ml) and highest FRAP value [369.48 ± 20.15
mM Fe (II) E/g DW]. TPC of free phenolic extracts of all citrus peels were significantly (p<
0.05) higher compared to the bound phenolic extracts with extract of calamansi showed the
highest TPC. Free- and bound phenolic extract of calamansi also had the highest α-amylase
inhibition activity (61.79 ± 4.13%; 45.30 ± 5.35%) respectively. The highest inhibitory effect in
α-glucosidase inhibition assay of free- and bound phenolic extracts were white Tambun pomelo
(41.06 ± 10.94%) and calamansi (43.99 ± 22.03%) respectively. Hence, the citrus peels could
be furthered study for their potential in management and/or prevention of diabetes.
The in vitro bioaccessibility of calcium, iron and zinc of breads added with different bread
spreads was determined. The mineral contents were assessed by flame atomic absorption
spectrophotometer and expressed in fresh weight (mg/100 g). For the mineral bioaccessibility
determination, in vitro gastrointestinal digestion was applied. Among the bread samples, calcium
content of wholemeal bread with chocolate hazelnut spread ranked the highest (159.96±0.869
mg/100 g). For iron, white bread with chocolate hazelnut spread (6.92±0.411 mg/100 g) showed
highest iron content while for zinc, white bread with peanut butter was the highest (1.82±0.015
mg/100 g). For calcium bioaccessibility, white bread with orange marmalade ranked the
highest (39.33±4.865%) while wholemeal bread with peanut butter (14.70±0.265%) showed
the lowest. The application of orange marmalade spread onto wholemeal bread increased the
iron bioaccessibility significantly (9.73±1.387%). The acidic properties attributed by organic
acids found in orange marmalade may favour both calcium and iron absorption. The zinc
bioaccessibility of white bread alone remained the highest (20.63±3.536%) while wholemeal
bread added with peanut butter (5.90±1.137%) showed the lowest. Overall, the addition of
bread spreads particularly peanut butter and chocolate hazelnut spread had increased mineral
contents of the bread samples. However, the presence of mineral enhancers (organic acids) and
inhibitors (phytate and polyphenols) played some significant role in influencing the mineral
bioaccessibility.
Soymilk, which can be called as plant based “milk” is a favourite traditional beverage in Asian with various beneficial health protective effects due to the presence of isoflavones. Mixing cereal grains into soymilk to make a wholesome beverage for breakfast becomes popular. However, dietary factors may affect the bioaccessibility of isoflavones. The aim of this current work was to evaluate changes in the bioaccessibility of isoflavones in soymilk after mixing with selected cereal grains following in vitro gastrointestinal digestion. The samples were subjected to in vitro gastrointestinal digestion with its isoflavones content determined before and after simulated gastric digestion and intestinal digestion with dialysis membrane. Soymilk contained 1.80 ± 0.03 mg daidzein and 2.12 ± 0.08 mg genistein in 100 ml, while bioaccessibility of soymilk daidzein and genistein were 11.24 ± 0.46% and 5.09 ± 0.25% respectively. The addition of cereal grains except barley in soymilk showed significant reduction (p
β-carotene, a type of provitamin A, is beneficial to our health. However, the compound needs to be released from its food matrix before being utilised by the body. Thus, understanding the bioaccessibility of β-carotene in the food consumed is a crucial step. The objective of this study was to determine the effect of various cooking methods on bioaccessibility of β-carotene in pumpkin and butternut squash. In vitro digestion was carried out on raw and cooked (steamed, boiled, and deep-fried) pumpkin and butternut squash. β-carotene was identified using RPHPLC. Generally, butternut squash (4.99±0.02mg/100g) had higher β-carotene content than pumpkin (4.34±0.04mg/100g). Thermal processing resulted in lower β-carotene content in pumpkin samples; however, it increased the β-carotene content in butternut squash samples. In term of bioaccessibility, thermal processes increased the percentage of bioaccessible β-carotene in both pumpkin and butternut squash samples. Raw pumpkin had 10.56±0.44% of bioaccessible β-carotene while raw butternut squash had only 1.65±0.04%. Bioaccessibility of β-carotene in deep-fried pumpkin and butternut squash were significantly higher than their raw sample with 68.86±0.86% (p
Vitamin D plays an important role in maintaining the physical health as well as the performance of athletes. This cross-sectional analytical study was conducted to determine vitamin D intake, sun exposure and skin types of both indoor and outdoor Malaysian athletes in the National Sports Institute, Bukit Jalil. Method: A total of 28 indoor (badminton, shooting, wushu and fencing) and 36 outdoor (athletics, football and hockey) athletes were recruited for this study. The dietary vitamin D intake was estimated using Vitamin D-specific Food Frequency Questionnaire (FFQ). The Sun Exposure Index (SEI) was calculated from Seven-day Sun Exposure Record while the skin types of athletes were determined using Fitzpatrick Skin Typing Questionnaire. Results: The mean age of the athletes was 21.02±4.11 years and their mean Body Mass Index (BMI) was 22.20±2.22 kg/m2. The mean body fat percentage of outdoor athletes was significantly lower than indoor athletes (p
Currently, data concerning the content of naturally occurring dietary folate in Malaysian foods is scarce. The aim of this study was to determine the folate content of vegetables, fruits, legumes and cereals that were commonly consumed among Malaysians. The total folate content of 156 samples (51 vegetables, 33 fruits, 22 legumes and legume products, and 50 cereals and cereal products) available in Malaysia was determined by microbiological assay using Lactobacillus casei (L. casei) after trienzyme treatment with protease, α-amylase and folate conjugase (from rat serum). An internal quality control system was used throughout the study by analyzing CRM 121 (wholemeal flour) and CRM 485 (lyophilized mixed vegetables); percent recovery (as mean ± SD) of 97 ± 2.0 and 101 ± 4.0 was obtained. The range of folate content in vegetables, fruits, legumes and cereals were 1-11 μg/100 g and 1-31on the basis of fresh weight and 1-31 µg/100 g and 2-156 µg/100 g on the basis of dry weight, respectively. This study has shown that some of these underutilized vegetables and fruits are good sources of folate and could fulfill the recommended dietary intake of total folate.
Microalgae can produce various natural products such as pigments, enzymes, unique fatty acids and vitamin that benefit humans. The objective of the study is to study the bioaccessibility of carotenoids (β-carotene and lycopene) and vitamin E (α- and β-tocopherol) of Nannochloropsis oculata and Chaetoceros calcitrans. Analyses were carried out for both the powdered forms of N. oculata and C. calcitrans, and the dried extract forms of N. oculata and C. calcitrans. In vitro digestion method together with RP-HPLC was used to determine the bioaccessibility of carotenoids and vitamin E for both forms of microalgae. Powdered form of N. oculata had the highest bioaccessibility of β-carotene (28.0 ± 0.6 g kg-1), followed by dried extract N. oculata (21.5 ± 1.1 g kg-1), dried extract C. calcitrans (16.9 ± 0.1 g kg-1), and powdered C. calcitrans (15.6 ± 0.1 g kg-1). For lycopene, dried extract of N. oculata had the highest bioaccessibility of lycopene (42.6 ± 1.1 g kg-1), followed by dried extract C. calcitrans (41.9 ± 0.6 g kg-1), powdered C. calcitrans (39.7 ± 0.1 g kg-1) and powdered N. oculata (32.6 ± 0.7 g kg-1). Dried extract C. calcitrans had the highest bioaccessibility of α-tocopherol (72.1 ± 1.2 g kg-1). However, β-tocopherol was not detected in both dried extract and powdered form of C. calcitrans. In conclusion, all samples in their dried extract forms were found to have significantly higher bioaccessibilities than their powdered forms. This may be due to the disruption of the food matrix contributing to a higher bioaccessibility of nutrients shown by the dried extract forms.
In current work, the nutritional composition, bioactive compounds, total phenolic contents and anti-oxidant activity of young Malaysian ginger rhizome were investigated. Proximate analysis and high performance liquid chromatography (HPLC) recruited to determine nutritional composition and bioactive compounds. The total flavonoid (TF) and total phenolic contents (TPC) of ginger rhizome were determined by aluminium chloride calorimetric assay and Folin-Ciocalteau reagent, respectively. 2,2’-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method were used to measure antioxidant capacity. The rhizome contained high moisture content and low level of carbohydrate and energy. 6-gingerol was the most abundant component in the selected ginger, and total flavonoid and phenolic content were reported to be 3.66±0.45 mg gallic acid/g and 10.22±0.87 mg quercetin/g of dry weight of rhizome, respectively. The rhizome also showed lower antioxidant activity than controls, with the IC 50 value of 46.5 vs. 15.5 for α-tocopherol and 22 for BHT. The results of this study predicted that the young ginger rhizome originated from Malaysia may exhibit anti-oxidative and anti-inflammatory potentials due to high levels of gingerols, total flavonoid and phenolic compounds and antioxidant capacity.
Introduction: This is a preliminary result of an on-going randomised cross-over trial to
compare the effects of consuming yellowstripe scad (YSS) and salmon, both rich in omega-3
fatty acids, on lipid profile, fasting glucose, body weight status, and blood pressure among
healthy overweight adults.
Methods: Fifty healthy overweight Malaysians aged 21-55 years
were recruited voluntarily through advertisements. During the first period of intervention,
subjects were randomised equally to receive eight weeks of either steamed whole YSS fish
(YSS group) or salmon fillet (salmon group), three days per week, obtaining approximately
7000 mg EPA+DHA per week. The diets were switched after an eight-week washout
period. Lipid profile, fasting glucose, body mass index, and blood pressure were evaluated
before and after each intervention period.
Results: The mean ages of YSS group (n=25)
and salmon (n=25) group were 30.6±9.1 and 27.9±7.1 years respectively. Both groups had
no statistically significant differences on socio-demographic characteristics (p>0.05). After
the first intervention period, there was a significant increase in total cholesterol within
the YSS group (p0.05). Both YSS and salmon
groups had significantly higher HDL-cholesterol levels after 8 weeks compared to baseline
(p0.05). However, there was a significant effect of time on
diastolic blood pressure (p