Bean, mung

Some members of the Liliaceae accumulate free azetidine-2-carboxylic acid in a much higher concentration than that found to be lethal to mung bean seedlings, but it is not incorporated into their proteins. Fowden (43) postulated that these plants either had a proline-incorporating system which was more specific than that found in other species, or some subcellular mechanism operated to prevent the homolog from reaching the sites involved in protein synthesis. Data which supported the first suggestion were subsequently obtained (116). 

In addition to effects on biochemical reactions, the inhibitors may influence the permeability of the various cellular membranes and through physical and chemical effects may alter the structure of other subcellular structures such as proteins, nucleic acid, and spindle fibers. Unfortunately, few definite examples can be listed. The action of colchicine and podophyllin in interfering with cell division is well known. The effect of various lactones (coumarin, parasorbic acid, and protoanemonin) on mitotic activity was discussed above. Disturbances to cytoplasmic and vacuolar structure, and the morphology of mitochondria imposed by protoanemonin, were also mentioned. Interference with protein configuration and loss of biological activity was attributed to incorporation of azetidine-2-carboxylic acid into mung bean protein in place of proline. 

Using this crude mung bean preparation, the production of (R)-p-nitrostyrene oxide was achieved in 82% ee and 83.5% yield. After recrystallization, greater than 99% ee was achieved. 

Figure 5.25 Enantioconvergent hydrolysis of epoxides (35) to the corresponding diols (36) using mung bean epoxide hydrolase.

Mung bean seedlings at different stages of development were treated with 24% (by weight) KOH to extract non-cellulosic polysaccharides as fully as possible. After neutralisation of the extracts, the polysaccharides were isolated by ethanol precipitation, and... 

Figure 6. Galactan synthase activity in relation to (l->4)-P-D-galactan content in the cell walls of mung bean seedlings...

As illustrated in Fig. 3, in both poplar stems and mung bean hypocotyls, basic isoforms became prevalent in mature, resting cells whereas in young, growing cells, neutral isoforms were predominant. 

Some properties of the different isoforms extracted from mung bean hypocotyi cell walls (called respectively PEa, PEP and PEy, a for the neutral isoform, P for the PME with a pi around 8.5 and y for the most basic one) are reported in Table 3. The three esterases differed not only in their pi but also by their Mr, their pH optimum and the ionic strength necessary for their solubilization. 

Table 3. Properties of mung bean purified PME isoforms...

Table 4. Kinetic parameters of mung bean PME isoforms. Assays performed at pH 7.6 in 150 mM NaCl values between brackets have been obtained at pH 5.6.

Contrary to AE from orange peels described by Williamson (2) this AE has a higher molecular mass and pi > 9. AE isolated from mung bean, however, has. similar MW and pi in agreement with the present findings (1). These differences could indicate the presence of several AE isoformes in different varieties of orange fruits. 

Table VI. Time-course Study of the Effects of Chondrillasterol on Germination and Hypocotyl and Radicle Elongation in Mung Beans...

Experiments with gaseous acetic acid have been performed for disinfection of seeds intended for the production of bean sprouts (Delaquis et al., 1999). Salmonella typhimurium and E. coli 0157 H7 were eradicated from the surface of mung bean seeds and it was reported that the seed germination loss was not too large. The seeds have often been the suspected source of contamination in sprout-associated outbreaks and sanitation methods that do not interfere with the germination of the seeds are appreciated. Other volatile chemical treatments have been tested for lethality to Salmonella spp. on alfalfa seeds and sprouts with varying results both on the efficacy of the disinfectant and its effect on sensory qualities (Weissinger et al., 2001). 

Delaquis, P.J., Sholberg, PL. and Stanich, K. (1999) Disinfection of mung bean seed with gaseous acetic acid . Journal of Food Protection, 62, 953-957. 

The major pathway probably proceeds via D-galacturonic acid and L-galactono-1,4-lactone, as these are converted to L-ascorbic acid by mitochondria prepared from peas and mung beans, but neither L-gulono-1,4-... 

MaeshimaM, Yoshida S. Purification and properties of vacuolar membrane proton-translocating inorganic pyrophosphatase from mung bean. JBiol Chem 1989 264 20,068-20,073. 

Yoshida S. Isolation of smooth endoplasmic reticulum and tonoplast from etiolated mung bean hypocotyls. in Methods in Enzymology, Vol. 228 (Walter H, Johansson G, ed.), Academic Press, New York, 1994, pp. 482-489. 

Harris N, Oparka KJ. Connections between dictyosomes, ER, and GERL in cotyledons of mung bean (Vigna radiata L.). Protoplasma 1983 114 93-102. 

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