Solanum muricatum / Pepino / Meloenpeer

Dit snoepje van de natuur is familie van de tomaat en paprika. De smaak doet denken aan een mix van peer en meloen met een vleugje komkommer. De vruchten zijn aan de buitenkant hard (zoals een appel) en hebben binnen in de vrucht een holte. In het holle gedeelte bevindt zich een goed smakend sap. Naast dat de meloenpeer erg lekker is, is hij ook erg gezond door het hoge gehalte vitamine C in de vruchten. Door de harde buitenkant zijn de vruchten lang houdbaar.

Meloenpeer zaaien: Zaai de pepino zaden vroeg in het voorjaar binnen in potjes. Verdeel een aantal zaadjes per potje en dek af met plastic folie. Zaai altijd 30 tot 40% meer. Er is nooit 100% kieming en zwakkere kiemplantjes kunnen gelijk weg gegooid worden. Zorg dat de grond constant vochtig en warm blijft. Na ongeveer 14 dagen bij 20°C komen de jonge meloenpeer plantjes op. Het plastic folie kan dan verwijderd worden. Als de kiemplantjes 5 cm groot zijn, kunnen ze worden opgepot. Doe 1 plantje per potje. Zet vervolgens de opgepotten meloenpeer plantjes op een zeer lichte plek.

Meloenpeer kweken: Wanneer het buiten mooi weer is, kunnen de jonge planten buiten afgehard worden. Als het ’s avonds onder 10°C wordt, moeten de planten weer naar binnen. De Meloenpeer planten kunnen in de moestuin, kas of een pot geplant worden, als de temperatuur niet meer onder de 10°C komt. De planten groeien optimaal al ze op een warme en zonnige plek groeien. Een meloenpeer plant groeit niet hard, het duurt erg lang voordat de eerste vruchten geoogst kunnen worden. In een kas groeien ze beter en produceren de planten meer vruchten.

Een pepino plant is een meerjarige plant, mits hij vorstvrij overwintert. Snoei de plant flink terug en bewaar de terug gesnoeide plant boven de 10°C. Geef hem in deze periode niet tot nauwelijks water. In het voorjaar als de temperatuur omhoog gaat zal de plant weer uitlopen.

The pepino (Solanum muricatum Aiton) is an herbaceous Andean domesticate grown for its juicy and aromatic fruits. Although it was a very important crop in the Andean region in pre-Columbian times (Prohens et al., 1996⇓), its 20th century prominence has not equaled that of its close relatives the tomato (Solanum lycopersicum L.) and potato (Solanum tuberosum L.). However, in the last three decades, there has been growing interest in the pepino from exotic fruit markets, and its cultivation has spread from its ancestral home in the Andes of South America to other countries such as New Zealand, Spain, and the Netherlands (Nuez and Ruiz, 1996⇓).
Fruit - raw. A juicy, sweet aromatic and very agreeable flavour, somewhat like a honeydew melon. The skin of some varieties has a disagreeable flavour. The fruit contains 35mg vitamin C per 100g, 7% carbohydrates and 92% water. The fruit should be harvested just before it is fully ripe and will store for several weeks at room temperature

Anticancer Res. 1999 Jan-Feb;19(1A):403-8. Extract of Solanum muricatum (Pepino/CSG) inhibits tumor growth by inducing apoptosis.
Ren W1, Tang DG.
Apoptosis, or programmed cell death, is characterized by certain distinct morphological and biochemical features. Most chemotherapeutic drugs exert their anti-tumor effects by inducing apoptosis. Therefore, an effective compound inducing apoptosis appears to be a relevant strategy to suppress various human tumors. In a search for tumor inhibitors from various kinds of plants, we found that extracts from Solanum muricatum (CSG) can inhibit tumor growth both in vivo and in vitro by inducing apoptosis.

A lyophilized aqueous fraction extracted from Solanum muricatum (CSG4) was used in this study. The human cell lines tested include: prostate (PC3, DU145), stomach (MKN45), liver (QGY-7721, SK-HEP-1), breast (MDA-MB-435), ovarian (OVCAR), colon (HT29) and lung (NCI-H209) cancer cells; NHP (prostate), HUVEC (umbilical vein endothelial cell), and WI-38 (lung diploid fibroblasts) normal cells. The cell survival was determined by either Cell Titer MTS cell proliferation kit or trypan blue dye exclusion assay. The apoptosis was analyzed by (a) apoptotic morphology by light microscopy; (b) DNA ladder formation; (c) PARP cleavage assay.

a) CSG possesses selective cytotoxic activity against all the tumor cell lines being tested. The LD50 value is 561-825 micrograms/ml. b) CSG showed a much lower cytotoxicity to NHP, HUVEC and WI-38 normal cell lines with LD50 value being 2.8-3.2 mg/ml, which is 3-6 fold higher than on tumor cells. c) The in vivo study demonstrated that injection of CSG (100 micrograms) directly into tumor mass can reduce the tumor volume dramatically in nude mice inoculated with MKN45 gastric cancer cells. d) CSG-mediated tumor growth inhibition is through induction of apoptotic cell death, as manifested by (a) typical apoptotic morphology; (b) DNA ladder formation; and (c) PARP cleavage assay.

Taken together, the present study suggests, for the first time, that CSG may represent promising new chemical entity which preferentially targets various tumor cells by triggering apoptosis.

J Food Sci. 2012 Nov;77(11):C1131-5. doi: 10.1111/j.1750-3841.2012.02944.x. Epub 2012 Oct 11. Antioxidant activity of ripe and unripe pepino fruit (Solanum muricatum Aiton). Sudha G1, Priya MS, Shree RB, Vadivukkarasi S.

Ripe and unripe exotic pepino fruit were evaluated for antioxidant activity, total phenols, and flavonoid content. The antioxidant potency was investigated by employing various established in vitro systems, such as 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2-2'-azinobis(3-ethylbenthiazoline-6-sulphonic acid (ABTS), hydroxyl radical scavenging, reducing power, ferrous ion chelation, ferric reducing antioxidant power (FRAP), and lipid peroxidation. The EC(50) values of ripe ethanolic extract on DPPH radical, reducing power, ferrous ion chelation, ABTS radical, FRAP, hydroxyl radical, lipid peroxidation (brain), and lipid peroxidation (liver) were obtained to be 2.20, 2.81, <5.00, 34.06, 8.53, 1.30, 1.75, and 0.51 mg/mL, respectively. However, the EC(50) values for unripe fruit extract were noted to be 3.75, 3.40, 11.25, 40.12, 9.75, 0.80, 1.91, and 0.63 mg/mL, respectively. Ripe fruit exhibited the highest values of antioxidant activity in all the scavenging assays except for hydroxyl radical scavenging assay. Ripe pepino had higher total phenol and flavonoid content than unripe fruit. This study suggests that possible mechanism of the biological activities may be due to free radical scavenging and antioxidant characteristics, which may be due to the presence of polyphenols in the fruit extracts.

The ripe and unripe pepino fruit have excellent antioxidant properties, so the results obtained in this study clearly indicate that pepino fruit has a significant potential to use as a natural antioxidant agent and possibly as a food supplement.

J Sci Food Agric. 2011 Jun;91(8):1517-22. doi: 10.1002/jsfa.4345. Epub 2011 Mar 28. Protective effects of an aqueous extract from pepino (Solanum muricatum Ait.) in diabetic mice. Hsu CC1, Guo YR, Wang ZH, Yin MC.

This study analysed the content of ascorbic acid, phenolic acids and flavonoids in aqueous and ethanol extracts of pepino (Solanum muricatum Ait.), and examined the protective effects of pepino aqueous extract (PAE) in a mouse model of diabetes. PAE at 1, 2 and 4% was supplied for 5 weeks.

Aqueous and ethanol extracts had similar levels of total phenolic acids, but PAE had a higher content of ascorbic acid and total flavonoids than the ethanol extract. PAE treatments at 2% and 4% significantly lowered plasma glucose level (P < 0.05); however, only the 4% PAE significantly elevated plasma insulin level at week 5 (P < 0.05). PAE treatments significantly decreased the levels of malonyldialdehyde and reactive oxygen species in kidney (P < 0.05); however, only the 2% and 4% treatments significantly reduced oxidised glutathione formation, increased glutathione level, and retained renal glutathione peroxidase and catalase activities (P < 0.05). PAE treatments at 2% and 4% significantly lowered renal interleukin (IL)-6 and tumour necrosis factor-α levels (P < 0.05); however, only the 4% treatments significantly diminished renal IL-1β and levels of monocyte chemoattractant protein-1 (P < 0.05). PAE treatments at 4% significantly decreased aldose reductase activity and sorbitol production in kidney (P < 0.05).

These findings support the suggestion that pepino aqueous extract could attenuate the progression of diabetes via its antioxidative, anti-inflammatory and antiglycative effects.