The objective of this study is to evaluate the antioxidant components, elastase inhibition activities, and melanin synthesis rates of Korean traditional Actinidia (Actinidia arguta) fruits and leaves depending on the ethanol extraction concentrations. The total polyphenol content was the highest in the 50% ethanol extract of both fruits and leaves, with values of 634.1 mg GAE/100 g and 3,985.2 mg GAE/100 g, respectively. The total flavonoid content was the highest in the fruit 90% extract and leaf 50% extract at 191.9 mg/100 g and 2655.6 mg/100 g, respectively. The vitamin C content was the highest in the 50% extract of leaves at 2990.3 mg/100 g. Elastase inhibition was the highest at 56.9% in the leaf 50% extract at a concentration of 1,000 μg/mL. Melanin synthesis inhibition showed the highest melanin synthesis inhibitory effect among the extracts, as the leaf 50% extract showed an inhibitory rate of 65% or more. Therefore, the antioxidant components, elastase inhibition activities, and melanin synthesis inhibitory rate were better in leaves than in fruits. The leaf 50% extract was particularly the best among the extracts. Korean traditional Actinidia leaves can be considered as potential sources for new functional materials.

Yield and fruit size are under the control of many interacting factors and crop failures can be caused by climatic extremes and poor flowering. Nevertheless, this study has shown that mulching, through the creation of improved soil properties and reduced environmental stress, has the potential to substantially increase A. arguta fruit size and yield. The mulched site performed better than the site without mulch in reducing soil temperature, increasing soil moisture and controlling available phosphorus. Moreover, mulching improved both yield and fruit size. In light of this, we hope that the results of our research will provide useful information for the cultivation of A. arguta in South Korea. However, it also seems necessary to conduct research on the use of different types of mulch and on the economic profitability of mulch in the future.

Soil properties are important environmental conditions affecting fruit quality and yield in new cultivars of Actinidia arguta. The yield of three A. arguta cultivars (cv. Autumn Sense, cv. Chungsan, and cv. Greenball) from Wonju city, South Korea was investigated from 2017 to 2019 and the relationships to soil properties are discussed. The yield of cv. Autumn Sense, cv. Chungsan, and cv. Greenball fruits ranged from 6.8 to 24.5, 14.0 to 29.0, and 10.5 to 38.5 kg/vine. cv. Autumn Sense had the highest soil organic matter content and soil C/N ratio over the three-year period. The yield of A. arguta fruits was positively correlated with soil C/N ratio and could be described by a power model (y = axb), suggesting that soil C/N ratio plays an important role in limiting the bioavailability and bioaccumulation of organic matter in A. arguta fruits. In addition, C/N ratio in the soil was influenced by the soil available phosphate. However, the threshold of the C/N ratio for A. arguta fruit differed according to cultivar, and especially the lowest threshold was observed in cv. Chungsan. Therefore, the application of an appropriate C/N ratio depending on the cultivar is required for improved fruit yield. Our results present the soil properties required to increase the yield of the new A. arguta cultivars in South Korea.

Environmental conditions are important in increasing the fruit sugar content and productivity of the new cultivar Autumn Sense of Actinidia arguta. We analyzed various soil properties at experimental sites in South Korea. A Pearson’s correlation analysis was performed between the soil properties and sugar content or productivity of Autumn Sense. Further, a decision tree was used to determine the optimal soil conditions. The difference in the fruit size, sugar content, and productivity of Autumn Sense across sites was significant, confirming the effects of soil properties. The decision tree analysis showed that a soil C/N ratio of over 11.49 predicted a sugar content of more than 7°Bx at harvest time, and soil electrical capacity below 131.83 μS/cm predicted productivity more than 50 kg/vine at harvest time. Our results present the soil conditions required to increase the sugar content or productivity of Autumn Sense, a new A. arguta cultivar in South Korea.

In this study, we tried to find out the most appropriate pre-processing method and to verify the feasibility of developing a low-price sensing system for predicting the hardy kiwis sugar content based on VNIRS and subsequent spectral analysis. A total of 495 hardy kiwi samples were collected from three farms in Muju, Jeollabukdo, South Korea. The samples were scanned with a spectrophotometer in the range of 730-2300 nm with 1 nm spectral sampling interval. The measured data were arbitrarily separated into calibration and validation data for sugar content prediction. Partial least squares (PLS) regression was performed using various combinations of pre-processing methods. When the latent variable (LV) was 8 with the pre-processing combination of standard normal variate (SNV) and orthogonal signal correction (OSC), the highest R2 values of calibration and validation were 0.78 and 0.84, respectively. The possibility of predicting the sugar content of hardy kiwi was also examined at spectral sampling intervals of 6 and 10 nm in the narrower spectral range from 730 nm to 1200 nm for a low-price optical sensing system. The prediction performance had promising results with R2 values of 0.84 and 0.80 for 6 and 10 nm, respectively. Future studies will aim to develop a low-price optical sensing system with a combination of optical components such as photodiodes, light-emitting diodes (LEDs) and/or lamps, and to locate a more reliable prediction model by including meteorological data, soil data, and different varieties of hardy kiwi plants.

Actinidia arguta (Actinidiaceae), which is commonly referred to as hardy kiwifruit, has been reported to possess anti-inflammatory, anti-allergic and antioxidative properties. The protective effect of the leaves and stems of A. arguta against amyloid β protein (Aβ) (25-35)-induced cultured neuronal cell death and memory impairment was investigated in the current study. Exposure of cultured cortical neurons to 10 μM Aβ (25-35) for 24 h induced significant neuronal death as assessed by a 3-[4,5-dimethylthiazol- 2-yl]-2,5-diphenyl-tetrazolium bromide (MTT) assay and Hoechst 33342 staining. However, A. arguta (10 and 50 μg/ ml) prevented Aβ (25-35)-induced apoptotic neuronal death in cultured cortical neurons. A. arguta also inhibited the 100 μM H2O2-induced decrease of the MTT reduction rate in cultured neurons. Memory impairment was produced by intracerebroventricular microinjection of 15 nmol Aβ (25- 35) and examined using the passive avoidance test in ICR mice. Chronic treatments with A. arguta (50 and 100 mg/ kg, 14 days, p.o.) significantly prevented memory impairment induced by Aβ (25-35), and A. arguta inhibited the Aβ (25-35)-induced increase of cholinesterase activity in the brains of memory impaired mice. These results suggest that A. arguta might be able to inhibit Aβ (25-35)-induced neuronal death and memory impairment via antioxidative and anti-cholinesterase effects and that A. arguta could have a therapeutic role for preventing the progression of neurodegeneration in Alzheimer’s disease.

본 연구의 목적은 토종다래의 용매별 추출물에 따른 약리활성에 대한 검증 및 효능 평가로서 토종다래의 항산화, 항염증에 대한 효과를 확인하였다. 염증 반응은 자극이 가해지면 histamine, serotonin, prostaglandin과 같은 혈관 활성물질에 의해 혈관 투과성이 증대되어 염증을 유발하고 cytokine, free radical, lysosomal enzyme 등 다양한 매개 인자가 관여한다. 자극에 의한 macrophage cell의 염증반응은 tumor necrosis factor-α(TNF-α), interleukin-6(IL-6), interleukin-1β(IL-1β)와 같은 pro-inflammatory cytokine의 발현이 유도되고, inducible nitric oxide synthase(i-NOS)와cyclooxygenase-2(COX-2)에 영향을 받는 유전자의 발현을 자극하게 되어 nitric oxide(NO) 등의 염증 인자가 생성된다. 이에 따라 토종다래 추출물의 항염증에 대한 연구를 위해 이에 영향을 주는 인자인 i-NOS, COX-2의 단백질 발현억제 작용을 확인하였다. 그 결과, HKE > HKA > HKW 순서로 높은 효능을 확인 할 수 있었다. 가장 효과가 좋은 HKE 처리군에서 다양한 염증성 인자의 mRNA 발현량을 확인하였다. 측정 결과, HKE(2,000 μg/mL)는 i–NOS, COX-2, IL-1β, IL-6, TNF-α mRNA 발현이 각각 93.2%, 27.9%, 96.4%, 89.4%, 73.9% 억제되는 효과를 확인할 수 있었다. 또한, HKE의 nuclear factor kappa B(NF-κB) 단백질 발현에 농도의존적으로 유의미한 결과를 확인하였으며, 이에 토종다래의 항염증효과는 LPS에 의한 TLR4의 자극에서 NF-κB 경로의 완화로 나타는 것임을 검증하였다. 결론적으로 토종다래는 70% ethanol 추출물(HKE)의 항염증 효과가 가장 높았으며, HKE는 대식세포에서 NF-κB 염증관련 경로의 억제로 세포 내 mRNA 및 단백질 수준에서의 염증인자들의 생성을 저해하여 항염증 효과가 명백히 확인되었다. 향후 본 연구팀은 토종다래의 항염증과 관련된 유효성분의 분리정제 및 구조분석을 진행할 예정이다.

The purpose of this study was to evaluate the effect of superheated steam drying on physicochemical and microbial characteristics of Korean traditional actinidia (Actinidia arguta) leaves. Actinidia leaves were dried at steam temperature of 350℃ and oven temperature of 150℃ for 40-200 sec. Moisture content and water activity decreased with increasing the drying time, while color values including L, a, and b values and total color difference (ΔE) increased as drying time increased. The relationship between moisture content and water activity showed an exponential fit with high correlation vlaue (R2=0.9909). Total phenolics and flavonoids content and antioxidant activity such as DPPH radical scavenging activity, ABTS radical scavenging activity, and FRAP assay of dried actinidia leaves increased with increasing the drying time up to 160 sec, but dramatically decreased at drying of 200 sec. The numbers of total areobic bacteria of leaves was not detected at drying time over 120 sec and coliform of all the samples was not detected. As a results, the superheated steam was an very effective drying method of increase to the nutritional and sanitary quality of dried Korean traditional actinidia leaves.

Background : Alzheimer`s disease (AD) is characterized by neuronal loss and extracellular senile plaque, whose major constituent is β-amyloid (Aβ), a 39-43 amino acid peptide derived from amyloid precursor protein. In cultures, Aβ directly induce neuronal cell death and can include excessive generation of free radicals and peroxidative injury to proteins, lipids, and other macromolecules. Actinidia arguta, generally called hardy kiwifruit, has been reported to possess anti-inflammatory, anti-allergic and antioxidative properties. The present study aims to investigate the neuroprotective effect of the leaves and stems of A. arguta using in vitro cultured neurons and in vivo experimental animals. Methods and Results : Primary cortical neuronal cultures were prepared using Sprague-Dawley (SD) rat fetuses on embryonic days 15. Neurotoxicity experiments were performed on neurons after 3-4 days in culture. Cultured neurons were treated with 10 μM Aβ (25-35) for 24 h to produce neurotoxicity. In addition, cultured neurons were treated with H2O2 (100 μM) for 15 min and then incubated for 12 h in H2O2-free medium. Viability of cultured neurons was measured by a colorimetric MTT assay. Hoechst 33342 staining of neurons was carried out to examine Aβ (25-35)-induced apoptotic neuronal death. A. arguta over the concentration of 10 to 50 ㎍/㎖ prevented Aβ (25-35) (10 μM)-induced apoptotic neuronal death, and inhibited H2O2-induced decrease of MTT reduction rate. These results suggest that oxidative stress is implicated in Aβ (25-35)-induced neuronal apoptotic death. Memory impairment was produced by intracerebroventricular (i.c.v) microinjection of 15 nmol Aß (25-35) and examined using passive avoidance test in ICR mice. Chronic treatments with A. arguta (14 days, p.o.) protected memory impairment induced by Aß (25-35). Conclusion : The present study suggests that A. arguta has a therapeutic role for preventing the progression of neurodegenerative disease such as AD.

본 연구는 열처리 온도 및 시간이 토종 다래(A. arguta) 퓨레의 품질 특성 및 항산화 활성에 미치는 영향을 알아보기 위해서 70, 80, 90℃의 온도에서 각각 1, 3, 5분간 열처리하여 pH, 당도, pulp 함량, 색도, 점도, 조직감 및 미생물 수 등의 품질특성과 비타민 C, 총 페놀, 항산화 활성을 분석하였다. pH, 당도 그리고 pulp 함량의 경우 열처리 온도가 증가하고 열처리 시간이 길어질수록 감소하는 경향을 나타내었고, L, a, b값과 갈변도는 증가하는 경향으로 나타났으며, 점도와 adhesiveness 또한 증가하는 경향을 나타내었다. 일반세균과 곰팡이 수는 열처리 온도가 증가하고, 시간이 경과함에 따라 감소하는 경향을 보였다. 대장균군과 효모는 모든 조건에서 검출되지 않았다. 비타민 C와 총 페놀 함량은 온도가 증가하고 열처리 시간이 길어질수록 감소하는 경향을 나타내었고 70℃온도에서의 열처리와 모든 열처리 온도에서 1분간 열처리 시 대조구와 유사하였고 90℃에서 5분간 처리 시 크게 감소하는 것으로 나타났다. 항산화 활성은 비타민 C와 총 페놀 함량과 유사한 결과를 나타내었고, 따라서 다래의 항산화 활성은 비타민 C와 총 페놀이 주요한 요인으로 작용한다고 사료된다. 본 연구의 앞선 결과를 통해서 다래 퓨레를 90℃에서 5분간 열처리 시 이화학적 특성과 항산화 활성이 크게 감소하여 품질이 저하되는 것을 확인할 수 있었다. 결과적으로 본 연구 결과는 다래 퓨레의 안정성 및 상품적 가치판단에 따른 기초자료를 제공할 것으로 사료된다.

The effect of storage temperature and the storage period of hardy kiwifruits on the fruit firmness, soluble solids and fruit weight were studied in this work. The investigation was carried out on the Sae-Han cultivar of Actinidia arguta. It has an edible smooth skin and contains high amounts of sugar and vitamin C (ascorbic acid). In this research, the measurement of fruit firmness, soluble solids, and fruit weight were carried out at various temperatures (5, 10, 15, and 20℃) during 14 days. Fruit firmness rapidly decreased and soluble solids content increased at 15 and 20℃. We also investigated the correlation between fruit firmness and soluble solids content. There was a strong correlation between fruit firmness and soluble solids content. That means that fruit firmness affect the soluble solids content of hardy kiwifruit.

울릉도 민속식물 31분류군 49점 추출물을 대상으로 최종농도 50μg/mL로 LPS에 의해 유도된 RAW 264.7 대식세포의 NO 생성량을 조사하였다. 그 결과, 다래(Actinidia arguta) 잎 가지, 헛개나무(Hovenia dulcis) 잎, 동백나무(Camellia japonica) 잎 가지, 말오줌나무(Sambucus sieboldiana var. pendula) 잎 가지, 왕호장근(Fallopia sachalinensis) 뿌리 순으로 항염 활성이 우수하게 나타났다. 이 중에서 다래 잎 가지, 헛개나무 잎, 동백나무 잎 가지 추출물을 LPS로 유도된 Raw 264.7 대식세포에서 최종농도가 10, 20, 40, 50μg/mL로 처리하여 NO 생성량과 세포생존율, PGE2 생성량을 측정하였다. 그 결과 다래 잎 가지(IC50=29.21μg/mL), 헛개나무 잎(IC50=27.34μg/mL), 동백나무 잎 가지(IC50=45.68μg/mL) 모두 NO 생성을 농도 의존적으로 유의성 있게 억제하였다. 또한 PGE2 측정결과 다래 잎 가지(IC50=21.06μg/mL), 헛개나무 잎(IC50=33.47μg/mL), 동백나무 잎 가지(IC50=43.90μg/mL)에서도 유의성 있는 억제효과를 보였다. 본 연구결과 다래 잎 가지, 헛개나무 잎, 동백나무 잎 가지의 추출물은 염증 유발의 중요 인자인 NO 및 PGE2 생성을 저해하여 우수한 항염증 효과를 보였다. 이들 소재에 대한 염증억제 유효성분 규명 및 그 작용기전을 추가적으로 연구함으로써 만성 염증질환의 예방과 치료에 효과적으로 사용할 수 있을 것으로 기대된다.

The Hardy Kiwifruit (A. arguta (Sieb. & Zucc.) Planch. ex Miq.) is one of the valuable species due to their edible fruit, high content of nutritious substances, especially abundant of vitamin C, and distinctive flavor and medicinal usage. In order to develop a new A. arguta cultivar with larger fruit and high yielding, 168 candidate plants were collected from wild population in 12 locations distributed 4 provinces (Chungbuk, Gangwon, Gyeongnam, Jeonbuk) from 1985 to 1987. A clone bank that contained highly productive, superior genotypes of A. arguta was assembled in 1988, and 32 excellent clones were selected in 1996 through the clonal test for the growth and fruiting. Evaluation on these clones was done for the fruiting characteristics, yield trial, and major agronomic traits, such as Average Fruit Length (FL) and Width (FW), and Weight of Fruit (WF) and Individual Yields (IY), during 6 years (1997~2002). After the final selection, a new A. arguta cultivar, “Sae-Han” with larger fruit and high yielding was registered as a new variety denomination and certificated variety production and merchandising in 2006 (Table 1). “Sae-Han” is a tetraploid plant and has ellipsoid fruit shape, and has particularly large fruit size (Fig. 1, Table 3). The major agronomic traits of “Sae-Han” showed the large values and selection effect with an average of 43.6 mm (FL), 36.1 mm (FW), 29.4 g (WF), and 17.5 kg (IY), which are 35.0%, 19.9%, 81.5%, and 124.4% compared to the mean of 29 sample trees, respectively (Table 2).

Hardy Kiwifruit (A. arguta (Sieb. & Zucc.) Planch. ex Miq.) is one of the valuable species due to their edible fruits, high content of nutritious substances, especially abundant of vitamin C, and distinctive flavor and medicinal usage. Therefore, we have developed a new cultivar of A. arguta with large fruits and high yielding. For this, 168 candidate plants were collected from wild populations in 12 locations from 4 provinces (Chungbuk, Gangwon, Gyeongnam, and Jeonbuk) from 1985 to 1987. A clone bank that contained highly productive, superior genotypes of A. arguta was assembled in 1988, and 32 excellent clones were selected in 1996 through the clone tests for growth and fruiting. From these clones, we have been regularly investigated yield trials for the fruiting characteristics to evaluation of major agronomic traits, which are the average of Fruit Length (FL), Fruit Width (FW), Weight of Fruit (WF) and Individual Yield (IY), during consecutive 6 years (1997~2002). Finally, we have selected the new A. arguta cultivar, “Dae-Sung” with large fruits and high yielding and registered as a new variety denomination and certificated for variety production and merchandising in 2006 (Table 1). This cultivar is characterized by a diploid plant and oblong type in the fruit shape, and is particularly characterized by large fruit size (Fig. 1, Table 3). The major agronomic traits of this cultivar showed the large selection effect with an average of 41.6 mm (FL), 29.9 mm (FW), 18.9 g (WF), and 25.9 kg (IY), which are 28.8%, -0.7%, 16.7%, and 232.0% compared to the mean of 29 sample trees, respectively (Table 2).

Hardy Kiwifruit (A. arguta (Sieb. & Zucc.) Planch. ex Miq.) is one of the valuable species due to their edible fruits, high content of nutritious substances, especially abundant of vitamin C, and distinctive flavor and medicinal usage. Therefore, we have developed a new cultivar of A. arguta with large fruits and high yielding. For this, 168 candidate plants were collected from wild population in 12 locations from 4 provinces (Chungbuk, Gangwon, Gyeongnam, and Jeonbuk) from 1985 to 1987. A clone bank that contained highly productive, superior genotypes of A. arguta was assembled in 1988, and 32 excellent clones were selected in 1996 through clone tests for growth and fruiting. From these clones, we have regularly investigated yield trials for the fruiting characteristics for evaluation of major agronomic traits, which are the average of Fruit Length (FL), Fruit Width (FW), Weight of Fruit (WF) and Individual Yield (IY), during consecutive 6 years (1997~2002). Finally, we have selected the new A.arguta cultivar, “Chil-Bo” with large fruits and high yielding and registered as a new variety denomination and certificated for variety production and merchandising in 2006 (Table 1). This cultivar is characterized by a tetraploid plant and spheroid type in the fruit shape, and is particularly characterized by large fruit size (Fig. 1). The major agronomic traits of this cultivar showed the large selection effect with an average of 28.4 mm (FL), 36.9 mm (FW), 18.2 g (WF), and 24.2 kg (IY), which are -12.1%, 22.6%, 12.4%, and 210.3% compared to the mean of 29 sample trees, respectively (Table 2).

Paternal inheritance of plastid genome was confirmed by PCR-sequencing in the interspecific cross between Actinidia arguta and A. deliciosa. Both coding region and spacer region in the plastid DNA were PCR amplified, restriction digested, or sequenced. PC