http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Fatty acid composition of shiitake mushrooms as affected by harvesting cycles
Mun Yhung Jung,Da Eun Lee,Hong Yu Cheng,Min Kyoung Lee,Gyeong Ho Lee,Yoon Young Hwang,Seon Hye Baek 한국버섯학회 2018 버섯 Vol.22 No.1
The fatty acid composition of shiitake mushrooms cultivated at the mushroom farms under the identical condition was analyzed using a GC-FID. The lipids in mushrooms were extracted with a solvent mixture of methanol and chloroform. The lipids were saponified and methylesterified to make fatty acid methylesters (FAME). The FAME was isolated, identified and quantified using a GC-FID with a highly polar cyano-siloxane type capillary column. Linoleic acid was the most abundant fatty acid, representing about 74-81% of total fatty acids. Palmitic acid was the second most abundant fatty acid found in shitake mushrooms. The composition of fatty acid metabolite profiles were not greatly different with harvesting cycles. However, the contents of fatty acids in mushroom was greatly dependent on the harvesting cylcles. The fatty acid of contents in mushrooms obtained at the 1st harvesting cycle was much higher than those in mushrooms obtain at the 3rd harvesting cycle.
Jung, Mun Yhung,Choi, Dong-Seong 한국식품과학회 2016 Food Science and Biotechnology Vol.25 No.6
The comparative protective effects of gallic acid with well-known synthetic antioxidants (tert-butylhydroquinone, butylated hydroxylanisole, propylgallate) on the thermal oxidations of corn and soybean oils during heating for 8 h at $180^{\circ}C$ were studied. The quantitative effects of gallic acid at three different concentrations on the time-course thermal oxidations in the two different vegetable oils were also studied for a prolonged heating of 6 days at $180^{\circ}C$. Gallic acid at 200 ppm exhibited higher protective activity than the synthetic antioxidants at the same concentration. Gallic acid also exhibited persistently strong protective activity, in a concentration dependent manner, on the changes in oxidation indices in corn and soybean oils throughout the prolonged heating period (6 days) at $180^{\circ}C$. The present results clearly suggested that gallic acid would be a potential natural substitute of synthetic antioxidants for the protection of vegetable oils during high temperature heating.
Jung, Mun Yhung,Lee, Min Kyoung,Park, Hee Jeong,Oh, Eun-Bi,Shin, Je Young,Park, Ji Su,Jung, Su Young,Oh, Jung-Hee,Choi, Dong-Seong Korean Society of Food Science and Technology 2018 Food Science and Biotechnology Vol.27 No.3
The impact of heat type, sample type, temperature and time on the heat-induced conversion of gingerols to shogaols in ginger were studied by an UHPLC-ESI-MS/MS. Heat treatments greatly induced the conversion of gingerols to shogaols in ginger. As the temperature increased, the faster conversion of gingerols into shogaols were observed. However, the efficiency of the heat-induced conversion differed greatly with the heat types. Moist heat treatment induced significantly higher quantity of shogaols than dry heat treatment. The moist heat treatment at $120^{\circ}C$ for 360 min induced the highest conversion, reaching to 2991 mg 6-shogaol per kg ginger. In addition, dry-heat induced conversion was affected by the sample type. The dry-heat treatment on dried powder induced significantly higher quantity of shogaols than that on sliced fresh ginger. This represents the first systematic comparative study on the heat and sample types on the heat-induced conversion of gingerols into shogaols in ginger.
Jung, Mun Yhung,Kang, Ju Hui,Choi, Yun Seo,Lee, Da Young,Lee, Ju Yeon,Park, Ji Su Elsevier 2019 Food chemistry Vol.274 No.-
<P><B>Abstract</B></P> <P>The analytical features of MP-AES for the determination of Mn in wine were studied as compared with ICP-OES. The optimum spectral line (403.076 nm) of MP-AES was different from that (259.373 nm) of ICP-OES. Significant matrix effect was observed with MP-AES, but not with ICP-OES. A simple and cost-effective MP-AES for the quantitation of Mn in wild grape (<I>Vitis coignetiae</I>) red wines were developed and validated. A standard addition method was used to compensate the matrix effects. The sensitivity of MP-AES was comparable to that of ICP-OES. MP-AES was sensitive, precise, accurate and reliable. The Mn concentration in the wild grape wines was in the range of 502–3627 μg L<SUP>−1</SUP>. MP-AES had a distinct drawback of low matrix tolerance. However, MP-AES had a clear advantage of the low running cost due to the use of nitrogen gas generated from air with a nitrogen generator.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A simple and cheap MP-AES was developed and validated for the quantitation of Mn in wine. </LI> <LI> The analytical features for the MP-AES were greatly different with those of ICP-OES. </LI> <LI> Significant matrix effect in wine sample matrices was observed with MP-AES, but not with ICP-OES. </LI> <LI> The low matrix tolerance of MP-AES was overcome by a standard addition method. </LI> <LI> The contents of Mn in wild grape (<I>Vitis coignetiae</I>) wines are reported for the first time. </LI> </UL> </P>