Greenhouse-grown bitter melon: production and quality characteristics.

BACKGROUND Bitter melon (Momordica charantia L.) is a medicinal fruit reported to have antidiabetic properties. To grow this tropical fruit year-round in temperate climates, greenhouse production is necessary, sometimes without insect pollinators. Suitable high-yielding varieties with good bioactivity need to be identified. This experiment evaluated the yield of six varieties of bitter melon under greenhouse conditions and their bioactivity in terms of total phenolic and saponin compounds and total antioxidant activity determined using four assays. RESULTS The larger varieties (Big Top Medium, Hanuman, Jade and White) were more productive than the small varieties (Indra and Niddhi) in terms of total fruit weight and yield per flower pollinated. The bioactivity (total phenolic and saponin compounds and antioxidant activity) of the two small varieties and Big Top Medium was significantly higher than that of the other three large varieties. Two antioxidant assays, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP), were shown to provide the strongest correlations with phenolic and saponin compounds of bitter melon. CONCLUSION Preliminary research has identified Big Top Medium as the most suitable variety for greenhouse production. The rich source of phenolic and saponin compounds and their associated antioxidant activity highlight bitter melon as a valuable food.

[1]  H. Kelebek,et al.  Comparative evaluation of the phenolic content and antioxidant capacity of sun-dried raisins. , 2013, Journal of the science of food and agriculture.

[2]  P. Roach,et al.  Effect of extraction conditions on total phenolic compounds and antioxidant activities of Carica papaya leaf aqueous extracts , 2013 .

[3]  Wen-Huey Wu,et al.  Wild bitter melon (Momordica charantia Linn. var. abbreviata Ser.) extract and its bioactive components suppress Propionibacterium acnes-induced inflammation. , 2012, Food chemistry.

[4]  G. Agbaje,et al.  Nutritional and antioxidant profiles of pumpkin (Cucurbita pepo Linn.) immature and mature fruits as influenced by NPK fertilizer. , 2012, Food chemistry.

[5]  M. Wolters,et al.  Personalized Diabetes and Cancer Medicine: A Rationale for Anti-Diabetic Nutrition (Bitter Melon) in a Supportive Setting , 2012 .

[6]  Jun Ma,et al.  Saponins from the traditional medicinal plant Momordica charantia stimulate insulin secretion in vitro. , 2011, Phytomedicine : international journal of phytotherapy and phytopharmacology.

[7]  H. Preuss,et al.  Bitter melon extracts in diabetic and normal rats favorably influence blood glucose and blood pressure regulation. , 2011, Journal of medicinal food.

[8]  S. Rudloff,et al.  Quantification of antidiabetic extracts and compounds in bitter gourd varieties , 2011 .

[9]  V. Nerurkar,et al.  Momordica charantia (bitter melon) inhibits primary human adipocyte differentiation by modulating adipogenic genes , 2010, BMC complementary and alternative medicine.

[10]  Pengyin Chen,et al.  Extraction, quantification, and antioxidant activities of phenolics from pericarp and seeds of bitter melons (Momordica charantia) harvested at three maturity stages (immature, mature, and ripe). , 2010, Journal of agricultural and food chemistry.

[11]  Karen Salandanan,et al.  Comparative analysis of antioxidant properties and fruit quality attributes of organically and conventionally grown melons (Cucumis melo L.). , 2009 .

[12]  C. Cervancia,et al.  Floral Biology and Pollination of Ampalaya (Momordica charantia L.) , 2009 .

[13]  E. Carey,et al.  Comparison of phenolic acids in organically and conventionally grown pac choi (Brassica rapa L. chinensis) , 2009 .

[14]  T. Shibamoto,et al.  Antioxidant assays for plant and food components. , 2009, Journal of agricultural and food chemistry.

[15]  S. Siriamornpun,et al.  Phenolic contents and antioxidant activities of bitter gourd (Momordica charantia L.) leaf, stem and fruit fraction extracts in vitro. , 2008, Food chemistry.

[16]  J. Prohens,et al.  Characterization, diversity, and relationships of the Spanish striped (Listada) eggplants: a model for the enhancement and protection of local heirlooms , 2008, Euphytica.

[17]  L. Ng,et al.  Antioxidant and free radical scavenging activities of wild bitter melon (Momordica charantia Linn. var. abbreviata Ser.) in Taiwan , 2008 .

[18]  T. Iwamoto,et al.  Antioxidant capacity of leafy vegetables as affected by high tunnel environment, fertilisation and growth stage. , 2007, Journal of the science of food and agriculture.

[19]  L. Yu,et al.  Methods for Antioxidant Capacity Estimation of Wheat and Wheat‐Based Food Products , 2007 .

[20]  L. Cisneros-Zevallos,et al.  Comparison of ABTS, DPPH, FRAP, and ORAC assays for estimating antioxidant activity from guava fruit extracts , 2006 .

[21]  J. Price,et al.  Application of manual assessment of oxygen radical absorbent capacity (ORAC) for use in high throughput assay of "total" antioxidant activity of drugs and natural products. , 2006, Journal of pharmacological and toxicological methods.

[22]  N. Hettiarachchy,et al.  Total Phenolic Contents and Phenolic Acid Constituents in 4 Varieties of Bitter Melons (Momordica charantia) and Antioxidant Activities of their Extracts , 2006 .

[23]  H. Sharma,et al.  The melon fruit fly, Bactrocera cucurbitae: A review of its biology and management , 2005, Journal of insect science.

[24]  Takuji Tanaka,et al.  Bitter gourd seed fatty acid rich in 9c,11t,13t-conjugated linolenic acid induces apoptosis and up-regulates the GADD45, p53 and PPARgamma in human colon cancer Caco-2 cells. , 2005, Prostaglandins, leukotrienes, and essential fatty acids.

[25]  Chi-Tang Ho,et al.  Antioxidant activities of buckwheat extracts , 2005 .

[26]  J. Hudson,et al.  Ethnomedicinal uses of Momordica charantia (Cucurbitaceae) in Togo and relation to its phytochemistr , 2005 .

[27]  R. Prior,et al.  Antioxidant Capacity of Tea and Common Vegetables , 1996 .

[28]  C. Lau,et al.  Anti-diabetic properties and phytochemistry of Momordica charantia L. (Cucurbitaceae). , 1996, Phytomedicine : international journal of phytotherapy and phytopharmacology.

[29]  S. Hiai,et al.  COLOR REACTION OF SOME SAPOGENINS AND SAPONINS WITH VANILLIN AND SULFUR1C ACID , 1976, Planta medica.

[30]  Tang Xiao-jun.  Phenolic Profiles and Antioxidant Activity of Momordica charantia L. of Different Varieties , 2011 .

[31]  C. Lii,et al.  Relationship between antioxidant and antiglycation ability of saponins, polyphenols, and polysaccharides in Chinese herbal medicines used to treat diabetes , 2011 .

[32]  V. Lattanzio,et al.  A reproducible, rapid and inexpensive Folin–Ciocalteu micro-method in determining phenolics of plant methanol extracts , 2009 .

[33]  Juming Tang,et al.  Evaluation of the antioxidant activity of asparagus, broccoli and their juices , 2007 .

[34]  E. L. Overholser,et al.  Factors affecting the vitamin C content of apples. , 1936 .