Hock Eng Khoo

Dr. Hock Eng Khoo

orcid

Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2017 in Food & Nutrition Research
Verified
Journal Article
Open access
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HKHock Eng Khoo
Hock Eng Khoo
AAAzrina Azlan
Azrina Azlan
STSou Teng Tang
Sou Teng Tang
SLSee Meng Lim
See Meng Lim
Anthocyanins are colored water-soluble pigments belonging to the phenolic group. The pigments are in glycosylated forms. Anthocyanins responsible for the colors, red, purple, and blue, are in fruits and vegetables. Berries, currants, grapes, and some tropical fruits have high anthocyanins content. Red to purplish blue-colored leafy vegetables, grains, roots, and tubers are the edible vegetables that contain a high level of anthocyanins. Among the anthocyanin pigments, cyanidin-3-glucoside is the major anthocyanin found in most of the plants. The colored anthocyanin pigments have been traditionally used as a natural food colorant. The color and stability of these pigments are influenced by pH, light, temperature, and structure. In acidic condition, anthocyanins appear as red but turn blue when the pH increases. Chromatography has been largely applied in extraction, separation, and quantification of anthocyanins. Besides the use of anthocyanidins and anthocyanins as natural dyes, these colored pigments are potential pharmaceutical ingredients that give various beneficial health effects. Scientific studies, such as cell culture studies, animal models, and human clinical trials, show that anthocyanidins and anthocyanins possess antioxidative and antimicrobial activities, improve visual and neurological health, and protect against various non-communicable diseases. These studies confer the health effects of anthocyanidins and anthocyanins, which are due to their potent antioxidant properties. Different mechanisms and pathways are involved in the protective effects, including free-radical scavenging pathway, cyclooxygenase pathway, mitogen-activated protein kinase pathway, and inflammatory cytokines signaling. Therefore, this review focuses on the role of anthocyanidins and anthocyanins as natural food colorants and their nutraceutical properties for health. Abbreviations : CVD: Cardiovascular disease VEGF: Vascular endothelial growth factor

18 February 2011 in Molecules
Verified
Journal Article
Open access
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HKHock Eng Khoo
Hock Eng Khoo
KPK. Nagendra Prasad
K. Nagendra Prasad
KKKin-Weng Kong
Kin-Weng Kong
Yueming JiangYueming Jiang
Yueming Jiang
AIAmin Ismail
Amin Ismail
Fruits and vegetables are colorful pigment-containing food sources. Owing to their nutritional benefits and phytochemicals, they are considered as ‘functional food ingredients’. Carotenoids are some of the most vital colored phytochemicals, occurring as all-trans and cis-isomers, and accounting for the brilliant colors of a variety of fruits and vegetables. Carotenoids extensively studied in this regard include β-carotene, lycopene, lutein and zeaxanthin. Coloration of fruits and vegetables depends on their growth maturity, concentration of carotenoid isomers, and food processing methods. This article focuses more on several carotenoids and their isomers present in different fruits and vegetables along with their concentrations. Carotenoids and their geometric isomers also play an important role in protecting cells from oxidation and cellular damages.

23 February 2010 in Molecules
Verified
Journal Article
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KKKin-Weng Kong
Kin-Weng Kong
HKHock Eng Khoo
Hock Eng Khoo
KPK. Nagendra Prasad
K. Nagendra Prasad
AIAmin Ismail
Amin Ismail
Chin Ping TanChin Ping Tan
Chin Ping Tan
NRNor Fadilah Rajab
Nor Fadilah Rajab
By-products derived from food processing are attractive source for their valuable bioactive components and color pigments. These by-products are useful for development as functional foods, nutraceuticals, food ingredients, additives, and also as cosmetic products. Lycopene is a bioactive red colored pigment naturally occurring in plants. Industrial by-products obtained from the plants are the good sources of lycopene. Interest in lycopene is increasing due to increasing evidence proving its preventive properties toward numerous diseases. In vitro, in vivo and ex vivo studies have demonstrated that lycopene-rich foods are inversely associated to diseases such as cancers, cardiovascular diseases, diabetes, and others. This paper also reviews the properties, absorption, transportation, and distribution of lycopene and its by-products in human body. The mechanism of action and interaction of lycopene with other bioactive compounds are also discussed, because these are the crucial features for beneficial role of lycopene. However, information on the effect of food processing on lycopene stability and availability was discussed for better understanding of its characteristics.

1 August 2009 in Journal of Food Composition and Analysis
Verified
Journal Article
Closed access
EIEmmy Hainida Khairul Ikram
Emmy Hainida Khairul Ikram
HKHock Eng Khoo
Hock Eng Khoo
AJAbbe Maleyki Mhd Jalil
Abbe Maleyki Mhd Jalil
AIAmin Ismail
Amin Ismail
SISalma Idris
Salma Idris
RMRuzaidi Azli Mohd Mokhtar
Ruzaidi Azli Mohd Mokhtar

2 April 2019 in Antioxidants
Verified
Journal Article
Open access
PDF file
HKHock Eng Khoo
Hock Eng Khoo
HNHui Suan Ng
Hui Suan Ng
WYWai-Sum Yap
Wai-Sum Yap
HGHenri Ji Hang Goh
Henri Ji Hang Goh
HYHip Seng Yim
Hip Seng Yim
The risk of macular degeneration can be reduced through the consumption of antioxidant-rich foods, supplements, and nutraceutical formulas. This review focuses on the antioxidants, vitamins, and minerals that have been reported for reducing the risk of macular degeneration and other eye-related diseases. Antioxidants including anthocyanins, carotenoids, flavonoids, and vitamins have been shown to reduce the risk of eye-related diseases. Anthocyanins extracted from berries are powerful antioxidants. Cyanidin, delphinidin, malvidin, pelargonidin, peonidin, and petunidin are anthocyanin aglycones detected in berries, currants, and other colored fruits and vegetables. β-Carotene, as well as xanthophyll lutein and zeaxanthin, have been reported to reduce the risk of macular degeneration. Flavonoids from plants help in the prevention of eye-related diseases through anti-inflammatory mechanisms. A combination of these antioxidants, vitamins, and minerals possess a synergistic effect on the prevention or risk reduction of macular degeneration. Formulas have been developed as dietary supplements to cater to the high demand from consumers and patients with eye problems. Many of the formulated dietary supplements that are sold in the market have been clinically proven for their efficacy to treat eye diseases. Although the bioactivities in the supplement capsules or tablets have been scientifically established for reducing risks of several diseases, which include macular degeneration and other eye-related diseases, knowledge on the right dosage, efficacy, and bioavailability of antioxidants, vitamins, and minerals is important for consumers. The information may help them make the best decision in choosing the right dietary supplements and nutraceuticals following the evidence-based recommended dosages and reference intakes for improving general health and preventing eye-related diseases. This review covers the potential causal factors involved in eye diseases, clinically proven treatments, and controversial findings on the antioxidants in the prevention of macular degeneration. Future studies should consider multiethnic and multicenter trials for eliminating potential bias in research.

1 December 2010 in Journal of Food Composition and Analysis
Verified
Journal Article
Closed access
AAAzrina Azlan
Azrina Azlan
KPK. Nagendra Prasad
K. Nagendra Prasad
HKHock Eng Khoo
Hock Eng Khoo
NANurnadia Abdul-Aziz
Nurnadia Abdul-Aziz
AMAlina Mohamad
Alina Mohamad
ZAZulkhairi Amom
Zulkhairi Amom