This study examined the bioactive compound content and the antioxidant activities of bitter melon (Momordica charantia Linn.) leaves. The content of vitamin C, beta-carotene, and total carotenoids was 69.77, 45.68, and 65.08 mg/100 g, respectively. To investigate the antioxidant capacity, bitter melon leaves were extracted using various concentrations of ethanol (60, 80, or 100%). Highest content of total polyphenols (18.07 mg gallic acid equivalent/g) and flavonoids (4.53 mg cathechin equivalent/g) was found in the 100% ethanolic extract of the leaves (E100). Also, the E100 extract showed the highest levels of 2,2'azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and α-α-diphenyl-β-picrylhydrazyl (DPPH) free radical scavenging activities. Reducing power was also the highest (39.21 mg Trolox equivalent/g) in E100 extract. The E100 extract effectively inhibited lipid peroxidation by 91.45% compared to the control group. Also, the E100 extract showed a cytoprotective effect against oxidative stress in HepG2 cells and decreased the generation of intracellular reactive oxygen species. These results suggest that bitter melon leaves could be regarded as a potential source of natural antioxidants.

This study aimed to investigate the changes in the γ-aminobutyric acid (GABA) content of bitter melon (Momordica charantia L.) cultivated from different regions, with different harvest times and at various maturation stages. Methods for observing the changes in GABA content were validated by determining the specificity, linearity, limit of detection (LOD), limit of quantification (LOQ), and precision and accuracy using the HPLC-FLD system. Results showed high linearity in the calibration curve with a coefficient of correlation (R2) of 0.9999. The LOD and LOQ values for GABA were 0.29 and 0.87 μg/mL, respectively. The relative standard deviations for intra- and inter-day precision of GABA were less than 5%. The recovery rate of GABA was in the range of 98.77% to 100.50%. The average content of GABA was 0.93 mg/g and Cheongju showed highest GABA content of 1.88 mg/g. As the time of harvest increased from May to September, the GABA content decreased from 1.56 to 0.86 mg/g. Also, maturation of the bitter melon fruit was associated with a decreased in GABA content.

Bitter melon (Momordica charantia) is used in traditional herbal medicine in many Asian countries for the treatment of several diseases such as diabetes, eczema, night blindness, psoriasis, and rheumatism. Especially, most reports concerning the biological activities of bitter melon have focused on its effects on diabetes and hyperglycemia. Also, bitter melon is regarded as a longevity food, suggesting that it has several beneficial effects on anti-aging and the maintenance of a healthy state. Thus, we investigated whether bitter melon could increase the capacity of exercise in this study. Interestingly, bitter melon fruit extract activated AMP-activated protein kinase (AMPK), which is important for regulating glucose homeostasis, mitochondrial content and exercise capacity. In addition, bitter melon extract increased the expression of enzymes involved in fatty acid oxidation such as mitochondrial uncoupling protein 3 (UCP3), carnitine palmitoyl transferase 1b (CPT1b), and pyruvate dehydrogenase lipoamide kinase isozyme 4 (PDK4). Moreover, exercise tolerance was much more enhanced in bitter melon treated animals compared to the non-treated control group. These results suggest that bitter melon is a promising candidate for the development of functional foods beneficial for physical strength and the enhancement of exercise capacity.

본 연구에서는 볶음 처리 후 여주의 총 phenolics, 총 flavonoids, 갈변물질(MRPs, maillard reaction products), 항산화 활성 및 α-glucosidase 저해활성을 비교하였다. 또한 alkaloids 유도체와 쓴맛 저감 효과를 평가하였다. 볶음 온도 및 시간이 증가함에 따라 볶음 처리된 여주는 총 phenolics, 총 flavonoids, MRPs, 항산화 활성 및 α-glucosidase 저해활성 역시 증가하였으나, alkaloid계 화합물 및 쓴맛은 감소하였다. 특히 200℃에서 15분 동안 볶은 여주는 총 phenolics, 총 flavonoids, MRPs, 항산화 활성 및 α-glucosidase 저해활성이 가장 높았고 alkaloid계 화합물 및 쓴맛은 가장 낮게 나타났다. 이 결과로부터 볶음 여주는 쓴맛이 저감되고 이들 추출물은 식품에서도 잠재적인 천연 항산화제로 사용할 수 있을 것으로 판단되었다.

Oral squamous cell carcinoma (OSCC) is one of the most common carcinomas in the head and neck area. Bitter melon extraction (Momordicacharantia, BME) has been used as a functional food to prevent and treat human health related issues. It has recently been reported that BME inhibits breast cancer cell growth by arresting cell cycle and promoting apoptosis. In this study, we aimed at proving the inhibitory action of BME on OSCC proliferation. We used two OSCC cell lines, SCC4 and Ca9-22. Both cell lines were treated with different concentrations (1%, 2%, and 5%) of BME. Cell viability was examined by MTT assay. DNA condensation was visualized by immunofluorescence microscope to determine the signs of the cell apoptosis. Cell numbers were significantly decreased in a dose-dependent manner by bitter melon at concentration of 1% of BME on Ca9-22 cell line (P=0.001) but no significant effect on SCC4 (P=0.124) at the same concentration. 2% BME treatment of the Ca9-22 cell line induces chromatin condensation and DNA fragmentation after 20 hours. It seems that BME inhibits the proliferation of Ca9-22 cell line by inducing apoptosis. Thus, BME may be used as a dietary supplement for prevention of OSCC.

In this study, contetnts of phenolic acid and isoflavone, and biological activities of soy sauce were compared the soy sauce added bitter melon powder (BMPs). After the fermentation, pHs were decreased from 5.83 (0% BMP), 5.47 (5% BMP), and 5.32 (10% BMP) to 5.28, 5.36, and 5.16 at 90 days, whereas the acidities of soy sauce were increased from 0.06%, 0.07%, and 0.09% to 0.30%, 0.28%, and 0.36% at 90 days, respectively. In addition, the salinities of soy sauce were decreased, while viable cell numbers including Bacillus and yeast were increased. The contents of total phenolic, isoflavone-aglycone, and phenolic acid and antioxidant and α-glucosidase inhibition activities were significantly increased for 90 days, while the isoflavone-glycoside contents were decreased. In Particular, soy sauce with 10% BMP at 90 days showed the highest contents of glutamic acid (GA, 9,876.09 mg/100 mL) and γ-aminobutyric acid (GABA, 325.02 mg/100 mL) contents than among other samples. Additionally, the radical scavenging activities (DPPH, ABTS, ⦁OH, and FRAP) and α-glucosidase inhibition activities of soy sauce with 10% BMP at 90 days were shown to be high 96.07%, 97.27%, 59.47%, 1.98%, and 79.96%, respectively.

In the published article “Bitter melon extract does not alter photoperiodic effects on reproduction of male golden hamsters. Dev. Reprod. 2017; 21(2):215-221. https://doi.org/10.12717/DR.2017.21.2.215,” the corresponding author’s name is given incorrectly. The Editorial Office of Korean Society of Developmental Biology would like to correct the corresponding author’s name. The Editorial Office apologizes for any inconvenience that it may have caused.

Present study aimed to determine the effect of ‘bitter melon’, a popularly used fruit in Bangladesh and several other Asian countries, on high-fat-diet-induced type 2 diabetes. To investigate the effect, ethanol extract from bitter melon (BME) as a dietary supplement with mouse chow was used. BME was found to significantly attenuate the high-fat diet (HFD) -induced body weight and total fat mass. BME also effectively reduced the insulin resistance induced by the HFD. Furthermore, dietary supplementation of BME was highly effective in increasing insulin sensitivity and reducing hepatic fat and obesity. These results indicate that BME could be effective in attenuating type 2 diabetes and could therefore be a preventive measure against type 2 diabetes.

Bitter melon (Momordica charantia, MC) has been used in traditional Korean medicine in treating diabetes. In addition, some reports were emerged, showing the antifertility activities of MC in mammals. We investigated the effects of ethanolic MC extract on the reproductive activity of golden hamsters whose spermatogenetic capacity is controlled by their photoperiods. The animals were divided into 4 groups: long photoperiod (LP) control, short photoperiod (SP) control, and LP animals treated with MC. The animals were orally ingested with low (0.03 g/kg) or high (0.15 g/kg) concentrations of the ethanolic extracts for 8 weeks on the daily basis. The control animals received the vehicle. The animals were then mated with age-matched females, experienced pregnancy. As results, the LP control animals showed active large testes but SP control animals displayed remarkably reduced testes. The animals treated with both concentrations of MC extracts demonstrated large testes, indicating fertile activity as animals in LP. LP control animals had litters as expected, but SP controls had no litters at all. MC extract showed the same results as LP animals in generating offsprings. These results suggest that the MC extract does not change the photoperiodic influence on reproductive activity of male golden hamsters.

본 연구는 여주 분말 첨가 된장의 발효 중 이화학적 특성, phytochemical 화합물(isoflavones과 phenolic acids) 및 생리활성 활성 변화를 측정하였다. 된장 발효 중 pH는 6.41-5.83에서 5.81-5.24로 감소하였고, 반면에 산도는 0.42-0.65%에서 1.28-1.48%로 증가하였다. 고초균과 효모 생균수, 염도 및 총 아미노산 함량은 발효 종기(60 일)에 증가하였다. 특히, 발효 후 10% 여주 분말 첨가 된장은 가바(GABA, 129.87 mg/100 g) 함량이 다른 된장 시료들과 비교하여 가장 함량이 높았다. 발효 후 된장은 발효 전 된장 시료보다 생리활성이 높았다. 발효 후 phytochemicals 화합물 중 isoflavone-aglycones과 phenolic acids는 증가하였고, 반면에 isoflavone-glycosides는 감소하였다. 게다가, 발효 후에 총 phenolics, isoflavone-aglycones과 phenolic acids 함량은 급격히 증가하였고, 이에 따라 항산화 활성과 α-glucosidase 저해활성이 증가하였다. 이들 결과로부터 여주 분말 첨가로 항산화와 항당뇨 활성이 개선된 새로운 타입의 된장 제조가 가능할 것으로 판단되었다.

본 연구에서는 기능성이 밝혀져 있는 여주 분말을 첨가 하여 쌀누룩을 제조하고 이 누룩을 이용하여 막걸리를 제조 하였다. 여주 분말-쌀누룩(BMP-RN)은 BMP를 0, 0.5, 1.0 및 2.0%로 쌀에 첨가하여 제조하였고, 막걸리 발효가 진행 되는 동안 발효 특성, 미생물 특성 및 항산화 특성을 확인하 였다. 막걸리 발효 중 pH는 담금 직후(발효 0일째) 각각 4.52(0% BMP-RN), 4.93(0.5%), 4.80(1.0%) 및 4.88(2.0%)에 서 발효 7일째 4.15, 4.30, 4.57 및 4.77로 감소하였고, 이에 상응하여 총산은 0.60~0.78%에서 1.18-1.42%로 증가하였 다. 가용성 고형분은 발효 초기(0일째) 2.2~4.4 oBrix에서 발효 종기(7일째)8.6~9.3 oBrix로 증가하였고 알코올 함량 은 발효 종기 13.0%로 증가하였다. 한편, 수용성 phenolics 함량은 발효 0일째 각각 0.92~1.41 mg/mL에서 발효 종기(7 일째) 1.85~2.48 mg/mL로 증가하였고 이에 상응하여 DPPH 와 ABTS 라디칼 소거활성 및 FRAP 환원력은 각각 발효 0일째 46.95~70.04%, 55.33~74.13% 및 0.629~1.243에서 발 효 7일째 54.98~83.4%, 70.34~92.39% 및 0.964~1.455로 증 가하였다. 여주 분말 첨가 막걸리가 여주 분말 무첨가 막걸 리(일반 막걸리)보다 수용성 phenolics 및 항산화 활성이 높았다. 이 결과로 여주-쌀누룩을 이용하여 기능성 막걸리 제조가 가능할 수 있을 것으로 판단되었다.

본 연구에서는 여주 분말(bitter melon powder, BMP) 첨 가 청국장 발효 중 β-glucosidase 활성 변화, 총 phenolics와 isoflavone 함량, 항산화 활성 변화 및 관능평가를 조사하였 다. 청국장 발효 중 β-glucosidase 활성은 48 hr까지는 증가 한 후 72 hr에는 감소하였으며, 총 phenolics, isoflavonemalonylglycoside 및 isoflavone-aglycone 함량은 증가하였 고 이에 상응하여 항산화 활성 역시 증가하였으나, 총 isoflavone 및 isoflavone-glycoside 함량은 감소하였다. 한편, 발효종기 5% BMP 첨가 청국장은 또 다른 시료들과 비교하 여 가장 높은 항산화 활성을 나타내었다. 특히, 발효 72 hr 후 5% BMP 첨가 청국장의 총 phenolics와 daidzein 함량 및 DPPH 라디칼 소거 활성, ABTS 라디칼 소거 활성 및 환원력은 각각 13.5 mg/g, 390.57 μg/g, 90.74%, 99.79% 및 1.705(OD593 nm) 있었다. 부가적으로 여주 분말이 첨가될수 록 청국장의 이취도는 감소하였다. 이들 결과로부터 여주 분말 첨가로 기호성과 항산화 활성이 개선된 새로운 타입의 청국장 제조가 가능할 것으로 판단되었다.

Bitter melon (Momordica charantia L.) is a tropical and subtropical vine of the family Cucurbitaceae, widely grown for edible fruit, which is among the most bitter of all vegetables. Bitter melon contains an array of biologically active plant chemicals including triterpenes, proteins, and steroids. The fruit is useful in gout, rheumatism and subacute cases of the spleen and liver diseases. It is supposed to purify blood and dissipate melancholia. It has also been shown to have hypoglycaemic properties (anti-diabetic) in animal as well as human studies. Raw materials of used in pharmaceuticals, health food, cosmetics, food, perfumery and other industries. However, bitter melon is not popular in Korea. For research, development and commercialization of bitter melon in Korea, we collected 13 varieties of bitter melon from domestic andabroad. We study biological and chemical characteristics of bitter melon. In general frui tsize and weight of Philippines and Japanese varieties was larger than that of Chinese and Korean. We are studying chemical analysis of useful compound (diosgenin and GABA) from bitter melon.