The antioxidant effects by pre-treatment of Hutgae fruit water and ethanol (30°, Soju) extract on refrigerated eels were analyzed. The antioxidant activities were measured through DPPH and ABTS scavenging effect, values of acidity, peroxide, carbonyl, and TBA. The peroxide prevention effects of linoleic acid and eel oil were also assessed. Regarding DPPH radical scavenging, Hutgae ethanol extract presented higher scavenging effects than vitamin C 5 mM solution (p<0.05). The eel’s peroxidation degree was measured through 21 days of refrigeration after cleaning and immersion into the extract solution for one hour. Upon measuring the values of four different peroxide indicators, those of eels pre-treated with Hutgae extracts were lower than those of eels untreated. The POV of Hutgae ethanol extract, vitamin C 5 mM, and the control was 11.1, 11.3, 15.5 meq/kg, respectively. Hutgae ethanol extract showed higher antioxidant activities in TBA value, and carbonyl value than other samples. In linoleic acid or eel oil, Hutgae extract was as superiorly effective in preventing peroxide generation of refrigerated eels as vitamin C 10 mM solution. In conclusion, pre-application of Hutgae water and ethanol (30°, Soju) extract on eels was proved to be competent in stopping peroxidation of eel in refrigeration.

The objective of this study was to investigate the sensory quality attributes for the development of soy sauce containing an extract of the fruit of Hovenia dulcis Thunb (Hutgae), also known as liver function improvement and hangover removal. Aqueous extracts of Hutgae fruit and Hutgae fruit-soy sauce were used for determining the sensory evaluation. The intensity of the sweet smell and taste was predominated in the Hutgae fruit extract (p<0.05). Various seasoning items, such as apples, pears, dried figs, Korean bramble (Bokbunja), citron (Yuza) and sun-dried hot pepper (Taeyangcho), were used to determine the suitable type of seasoned soy sauce with the Hutgae fruit extract. In the sensory analysis, the highest overall preference (acceptance score 5) was obtained from the pear extract added to soy sauce with the Hutgae fruit. The overall preference of Yuza (score 4.9) and Taeyangcho (score 4.5) extracts also very well-matched the seasoning items for soy sauce with the Hutgae fruit extract. There was no difference among the extract mixtures of multi-seasoning items added to soy sauce with the Hutgae fruit extract. As more pear extract was added, a higher overall preference was obtained. On the other hand, as the more Yuza extract was added, the higher flavor intensity without the change of the overall preference was obtained. The overall preference of soy sauce with the pear- Yuza-Taeyangcho extract mixture was not different between with or without the Hutgae fruit extract. However, the overall preference (score 5.6) was significantly higher in the pear extract added to soy sauce with the Hutgae fruit extract compared with the pear extract added to soy sauce without the Hutgae fruit extract (score 4.8). These results suggest that soy sauce with the Hutgae fruit-pear extract mixture may be useful as a functional seasoning for various salad dressings.

In this study, the anti-inflammatory activities of the extracts of different parts of Hovenia dulcis such as leaves, stems, and roots were investigated. Among them, the roots extract (RE) showed the most potent suppressive effect against pro-inflammatory mediators in LPS-stimulated mouse macrophage cells. RE induced dose-dependent reduction of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and concomitantly reduced the production of NO and PGE2. Additionally, pre-treatment with RE significantly suppressed the production of inflammatory cytokines, such as tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, and IL-6, as well as mRNA levels. Moreover, phosphorylation of mitogen-activated protein kinases (MAPKs) and nuclear translocation of nuclear factor-kappa B (NF-kB) were also strongly attenuated by RE in RAW264.7 cell. Furthermore, RE induced HO-1 expression through nuclear translocation of nuclear factor E2-related factor 2 (Nrf2) and increase HO-1 activity in RAW264.7 macrophages. Therefore, these results indicate that RE strongly inhibits LPS-induced inflammatory responses by blocking NF-kB activation, inhibiting MAPKs phosphorylation, and enhancing HO-1 expression in macrophages, suggesting that RE of H. dulicis and a major component, 27-O-protocatechuoylbetulinic acid could be applied as a valuable natural anti-inflammatory material.

Hovenia dulcis Thunb fruits were successively extracted with hot water, water, methanol, ethyl acetate, and chloroform. The crude extracts were investigated for potential antioxidant by measuring scavenging against DPPH free radicals, reducing power, superoxide radicals, and protection of protein damage and cultured cells from a lethal dose of hydrogen peroxide (H2O2). In all chemical assays used, the hot water extract of H. dulcis fruits, which contained 61.14±2.57 (Tannic acid mg/g extract, n=3) of total phenolic compounds contents exhibited highest activity in in vitro models of DPPH free radical scavenging activity, reducing power assay, superoxide radical scavenging activity and protection of protein damage. In addition, the hot water extract protected cultured RAW 264.7 macrophages from a lethal dose of H2O2 and reduced reactive oxygen species level in RAW 264.7 cells.

헛개나무 추출물을 이용하여 항산화, 아질산염소거 및 알콜분해 효과 등을 조사한 결과는 다음과 같다. 헛개나무 잎과 과병의 용매별 추출수율을 측정한 결과 잎은 물층, 과병에서는 메탄올층에서 각각 높게 나타났으며, 에탄올 추출물을 헥산, 클로로포름, 에틸아세테이트, 부탄올 및 물과 같은 용매를 이용하여 계통분획한 후 추출수율은 잎과 과병 모두 물분획층에서 높게 나타났다. 메탄올 에탄올, 헥산, 클로로포름 및 물 추출물을 이용하여 항산화 효과 및 아질