Young-Sang Lee

Prof. Dr. Young-Sang Lee


Research Focus & Metrics

Academic Career Length

26Years (2001-Present)

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

Representative Publications

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1 October 2013 in HortScience
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SBShiva Ram Bhandari
Shiva Ram Bhandari
BJBo-Deul Jung
Bo-Deul Jung
HBHum-Young Baek
Hum-Young Baek
YLYoung-Sang Lee
Young-Sang Lee
To understand ripening-dependent changes in phytonutrients, five commercial cultivars of red peppers ( Capsicum annuum L.) grown in an open field in Taean, South Korea, were selected and their fruits were harvested at green mature (GM), intermediate breaker (BR), and red ripe (RR) stages and their phytonutrient contents and antioxidant activities were compared. Three major patterns in relation to ripening progress were observed. First, continuous increases were observed in vitamin C, total phenol, vitamin E (especially α-tocopherol), total free sugar, β-carotene, linolenic acid content, and antioxidant activity. Second, decreasing patterns were observed in phytosterols (campesterol, stigmasterol, and β-sitosterol) and linoleic acid. Third, total flavonoid and squalene contents were relatively higher at the BR stage compared with the GM and RR stages. These results indicate that each phytonutrient has a unique pattern of accumulation and degradation during the fruit-maturing process. Unlike the mentioned phytonutrients, which showed similar patterns in all tested cultivars, capsaicinoids exhibited quite different patterns of ripening-dependent changes among the cultivars. Throughout the ripening processes, positive correlations with antioxidant activity were observed in vitamin E ( r = 0.814**), β-carotene ( r = 0.772*), vitamin C ( r = 0.610**), and total phenol ( r = 0.595**) contents, whereas capsaicinoids, total flavonoid, and phytosterols exhibited no or slightly negative correlations. In conclusion, the ripening of red pepper fruits is accompanied by continuous increments in various phytonutrients and subsequent antioxidant activity.

27 October 2016 in Horticulture, Environment, and Biotechnology
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Journal Article
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SBShiva Ram Bhandari
Shiva Ram Bhandari
UBUsha Bashyal
Usha Bashyal
YLYoung-Sang Lee
Young-Sang Lee

3 December 2018 in Food Science & Nutrition
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YLYoung-Sang Lee
Young-Sang Lee
YOYejin Oh
Yejin Oh
TKTae‐Hyung Kim
Tae‐Hyung Kim
YCYoo‐Hyun Cho
Yoo‐Hyun Cho
Aseptic‐packaged cooked rice (APCR) is a rice‐based food product with a rapidly increasing market size, and APCR made of fragrant rice (FR) has recently appeared on the market. The fragrance of FR is produced by a combination of odoriferous compounds, among which 2‐acetyl‐1‐pyrroline (2AP) has been identified as the most important contributor to overall aroma. This study describes the development of a method to quantify 2AP in FR‐based APCR using headspace solid‐phase microextraction (SPME) coupled with gas chromatography–mass spectrometry (GC‐MS). The recovery of 2AP spiked into APCR was lower than 10%, which suggests significant matrix effects and inappropriateness of external standard‐based calibration. For standard addition calibration method, up to 1,000 ng of 2AP were spiked into APCR containing 0% to 100% FR. Subsequent regression analyses of recovered peak area (Y) as a function of the amount of 2AP spiked (X) yielded highly linear calibration curves (R2 > 0.9917) with consistent slopes (RSD = 2.7%), regardless of FR composition. Y‐intercepts, however, which represent the amount of 2AP in APCR without spiking, increased linearly (R2 = 0.9898) in proportion to the composition of FR in the APCR. The amount of 2AP in APCR, determined by extrapolating the standard addition calibration curves, also increased linearly (R2 = 0.9963) as a function of FR composition. Practicality of developed method was tested by monitoring 2AP contents in APCR under realistic storage conditions, which successfully demonstrated 38% and 60% 2AP reductions in APCR of 20% FR after 1 and 2 months of storage at 25°C, respectively. The present study demonstrates that a standard addition method, whereby up to 1,000 ng of 2AP standard is spiked into 4 g of APCR containing 5%–100% FR in a 20‐mL headspace vial followed by SPME/GC‐MS, may serve as an effective means of quantitating 2AP in fragrant rice‐based APCR.


21 April 2012 in Horticulture, Environment, and Biotechnology
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SBShiva Ram Bhandari
Shiva Ram Bhandari
SBSunita Basnet
Sunita Basnet
KCKyu Hwan Chung
Kyu Hwan Chung
KRKi-Hyun Ryu
Ki-Hyun Ryu
YLYoung-Sang Lee
Young-Sang Lee

30 April 2012 in Journal of Occupational Medicine and Toxicology
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MLMyeong-Seop Lee
Myeong-Seop Lee
YLYoung-Sang Lee
Young-Sang Lee
HLHae-Hyeog Lee
Hae-Hyeog Lee
HSHo-Yeon Song
Ho-Yeon Song
Backgrounds: Previous studies suggested that endocrine disruptors (ED) are toxic on preimplantation embryos and inhibit development of embryos in vitro culture. However, information about the toxicity of endocrine disruptors on preimplantation development of embryo in human reproductive environment is lacking. Methods: Bisphenol A (BPA) and Aroclor 1254 (polychlorinated biphenyls) were used as endocrine disruptors in this study. Mouse 2-cell embryos were cultured in medium alone or vehicle or co-cultured with human endometrial epithelial layers in increasing ED concentrations. Results: At 72 hours the percentage of normal blastocyst were decreased by ED in a dose-dependent manner while the co-culture system significantly enhanced the rate and reduced the toxicity of endocrine disruptors on the embryonic development in vitro. Conclusions: In conclusion, although EDs have the toxic effect on embryo development, the co-culture with human endometrial cell reduced the preimplantation embryo from it thereby making human reproductive environment protective to preimplantation embryo from the toxicity of endocrine disruptors.