Marah macrocarpus

Figure 6. Mass fragmentograms of the acidic fraction from an extract of Marah macrocarpus endosperm. Ions in the mass spectrum of GAi Me TMS ("shown above) were examined. The extract was run as the Me TMS derivative on a MS 902 spectrometer coupled to a Varian 2700 GC via a membrane separator. GC-MS conditions—3% OV-17 on 100-120-mesh Gas Chrom Q in a 2 m X 0.2 cm i.d. column. Temperature—200°C for 5 min then programmed at 4°C/min. Helium flow—16.5 cm3/min. Electron energy—70 eV accelerator potential— 2.9 KV separator temperature—226°C source temperature—250°C.

Cell-free systems provide a rapid and convenient method for preparing GA and GA-precursors with high specific radioactivity, although on a relatively small scale. [ C]-labeled ent-kaurenoid precursors of GAs have been obtained from [2- C] mevalonic acid by incubating with cell-free systems from endosperm of Marah macrocarpus (83) or Cucurblta maxima (84,85) ... 

Hasson, E.P., West, C.A. "Properties of the system for the mixed function oxidation of kaurene and kaurene derivatives in microsomes of the immature seed of Marah macrocarpus. Electron transfer components." Plant Physiol., 1976, 58, U79-U8U. 

The biosynthesis pathway of GAs in plants has long been studied since their discovery as endogenous growth regulators. There have been two key approaches to unravel the biosynthetic routes and identify the genes encoding the biosynthetic enzymes. First, a cell-free system prepared from immature seeds of dicotyledonous species such as Marah macrocarpus and Cucurbita maxima allowed researchers to purify and characterize the GA... 

Enzyme preparations from seeds of Marah macrocarpus and Malus domestica convert GAg to GA7 via 2,3-dehydroGAg. 

Fig. 2. Metabolic pathways from GA in enzyme preparations from embryo-endosperm of Marah macrocarpus and embryos of Malus domestica...

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