Toxicities of 10 insecticides were examined against late third instars of Culex tritaeniorhynchus using the direct-contact mortality bioassay. Six geospatially distant field mosquitoes were collected from Chuncheon-si (designated CC-CT), Hwaseong (HS-CT), Seosan (SS-CT) Jeonju (JJ-CT), Daegu (DG-CT), and Busan (BS-CT) in the Republic of Korea (ROK). Marked regional variations of insecticide susceptibility were observed. Field populations of SS-CT, JJ-CT and DG-CT from agricultural areas showed higher to extremely higher insecticide susceptibility to pyrethroids than those of CC-CT, HS-CT and BS-CT strains from none agricultural areas. Extremely high to low levels of susceptibility were measured: bifenthrin, susceptible ratio (SR) = 2.7–896.3; β-cyfluthrin, SR = 1.8–633.3; α-cypermethrin, SR = 1.2–1,051.9; deltamethrin, SR = 1.3–711.1; permethrin, SR = 1.5–1,053.4 etofenprox, SR = 2.2–29.3; chlorfenapyr, SR = 5.1–103.6; chlorpyrifos, SR = 2.3–337.0; fenitrothion, SR = 2.0–142.3 and fenthion, SR = 1.4–186.2. Culex tritaeniorhynchus populations from rice paddies had been under heavy selection pressure due to the agricultural insecticides and that’s why the mosquito species demonstrated high resistance to pyrethroids which were used for a long time to control agricultural pests in the localities. These results indicate that careful selection and rotational use of these insecticides mayresult in continued satisfactory control against field populations of Japanese encephalitis vector mosquitoes.

Background : 1-Deoxynojirimycin (DNJ) is a representative compound of the antidiabetic constituent in mulberry leaves (Morus alba L.). The hot water extracts of mulberry leaves were fermented with lactic acid bacteria in order to analysis the changes of the DNJ contents and α-glucosidase inhibition. Methods and Results : The mulberry leaves were extracted with hot water (121℃, 3 hr). The extracts were fermented with nine strains of lactic acid bacteria such as Lactobacillus acidophilus, in order to increase the contents of DNJ and α-glucosidase inhibition. DNJ contents in the fermented extracts were determinated by HPLC analysis. The α-glucosidase inhibition was mesured by comparing dose-inhibition curves of α-glucosidase and IC50 value. The DNJ contents after fermentation have increased in the almost fermented extracts. Especially, DNJ of the extracts fermented with L. acidophilus was increased from 8.38 ㎍ ㎖ -1 to 21.77 ㎍ ㎖-1. IC50 values of the α-glucosidase inhibition were shown to be decreased in the fermented extracts. The extracts fermented with L. casei KCTC 3109 was determined at 290.04 ㎍ ㎖-1, resulting it is lower about 140 ㎍ ㎖-1 than 429.76 ㎍ ㎖-1 of the control. Conclusion : From the above results, we may suggest that the lactic acid fermentation of mulberry leaves extracts can more enhance the hypoglycemic activities such as DNJ contents.

Background : Ancanthopanax senticosus Fruits Extracts were studied in order to develop as functional pigment. The extracts were evaluated for physicochemical properties and biological activity. Methods and Results : Ancanthopanax senticosus fruits extracts were extracted by the rate of ethanol and distilled water in 1% citric acid. The extracts were evaluated for physicochemical properties by chromaticity, total sugar content, free sugar content, acidity, total anthocyanin contents. Total sugar and acidity were 0.10 brix and 0.44% respectively. Fructose and glucose were 1.54% and 0.36% respectively. The 60% ethanol extracts showed the highest extraction yield and total anthocyanin content. The α-glucosidase inhibitory activity of 60% and 80% ethanol extracts higher than other extracts. Conclusion : These results suggest that Ancanthopanax senticosus fruits extracts may be useful purple pigment for anti-diabetes activity.

Background : Aerial parts of Angelica gigas were studied in order to develop as functional pigment. The extracts were evaluated for physicochemical properties and biological activity. Methods and Results : Aerial parts of Angelica gigas were extracted by the rate of ethanol and distilled water. The extracts were evaluated for physicochemical properties by chromaticity, total sugar content, free sugar content, acidity, chlorophyll and carotenoids contents. Total sugar and acidity were 0.90 brix and 2.84% respectively. Chlorophyll and carotenoids contents were 0.24 and 0.04% respectively. The extracts were evaluated for biological activity by anti-inflammatory and anti-diabetes activity. Cell viabilities were measured by MTT assay. Effect of extracts on nitric oxide (NO) production from RAW264.7 cells was accessed by Griess reagent assay. Extracts to RAW 264.7 cells reduced amounts of nitrite by 76.0%. Conclusion : These results suggest that aerial parts of Angelica gigas Nakai may be useful pigment for anti-inflammatory and anti-diabetes activity.

자가불화합성 작물인 스테비아는 순도를 유지하기 위하여 삽목에 의해 번식하고 있으나 그 소요기간과 증식률이 낮다. 본 실험에서는 액아로부터 완전한 식물계로 분화시켜 대량 증식을 위한 기내배양조건을 알고자 하였으며 그 결과를 요약하면 다음과 같다. 1. Murashige-Skoog(MS) 기본 배지에 NAA와 kinetin을 단독 처리할 때 액아로부터 shoot분화가 가장 좋은 경우는 NAA는 0.01-0.05mg/의 범위였고, kinetin은 0.5-1.0mg/의 범위이었다. 2. MS배지에서 shoot분화는 NAA 0.01-0.05mg/와 kinetin 0.5-1.0mg/을 조합처리하였을 때 좋았다. 3. MS배지의 salt strength를 달리할 때 1 MS가 12XMS보다 shoot분화와 생육에서 좋을 결과를 보였다. 그러나 root분화는12XMS에서 높았다. 4. 이상의 결과로보아 스테비아는 단시일 내에 많은 양을 증식시킬 수 있으며 shoot분화와 root 분화시 배지의 염류농도와 홀몬농도를 달리하는 것이 효율적이다.