Seed coats

Miscellaneous Alkaloids. Stukimic acid (57) is a precursor of anthranihc acid (28) and, in yeasts and Escherichia coli (a bacterium), anthranHic acid (o-aminobenzoic acid) is known to serve as a precursor of tryptophan (26). A similar but yet unknown path is presumed to operate in higher plants. Nonetheless, anthranHic acid itself is recognized as a precursor to a number of alkaloids. Thus damascenine [483-64-7] (134), C qH NO, from the seed coats of JSHgella damascena has been shown (95) to incorporate labeled anthranHic acid when unripe seeds of the plant are incubated with labeled precursor. 

Miscellaneous Applications. PEIs and their derivatives ate used as cementation auxihaties in cmde oil exploration (459), and for breaking cmde oil emulsions (460) in cmde oil extraction. Seed coatings of water-soluble copolymers containing polyethyleneimine have been developed (461). Polyethyleneimine derivatives have positive photoresist properties (462) amidated polyethyleneimines improve the flow properties of cement (463) and with few exceptions, A/-acyla2iddines act as chemical sterilisers for insects (464). 

Toxic Constituents. The seed coat of European beechnut contains an unidentified toxic substance that makes the feeding of beechnut cake to certain farm animals ha2ardous (47). A toxic concentration (up to 4000 ppm) of barium found in some Bra2il nut kernels (30,48) has been reported to... 

Seeds. Seeds are produced in pods, usually containing three almost spherical-to-oval seeds weighing 0.1—0.2 g. Commercial varieties have a yellow seed coat plus two cotyledons, plumule, and hypocotyl-radicle axis. The cotyledons contain primarily protein and Hpid bodies (see Fig. 1). Cottonseed. 

Sunflower. Two types of sunflowers are grown in the United States. Varieties grown for oilseed production, ca 85% of crop, are generally black-seeded, having thin seed coats that adhere to the kernels. These contain 40—50% oil and ca 20% protein. Nonoilseed varieties, ca 15% of crop, sometimes referred to as confectionery, striped, or large-seeded sunflowers, have striped, relatively thick hulls that do not adhere to the kernels. These contain 20—30% oil and are usually larger than seeds of oilseed varieties. 

Seeds. The sunflower seed (achene) is four-sided and flattened, ca 9 mm long x 4-8 mm wide, having a black or striped gray and black seed coat (pericarp) enclosing a kernel. The kernel contains protein and Hpid bodies. 

Compositions of the four oilseeds are given in Table 2. All except soybeans have a high content of seed coat or hull. Because of the high hull content, the cmde fiber content of the other oilseeds is also high. Confectionery varieties of sunflower seed may contain up to 28% cmde fiber on a dry basis (8). Soybeans differ from the other oilseeds in their high protein and low oil content. AH these oilseeds, however, yield high protein meals when dehuUed and defatted. 

Soybeans. Vktuady ad soybeans processed in the United States are solvent-extracted with hexane to recover the od. This traditional process is outlined in Figure 4. Beans arriving at the plant are cleaned and dried, if necessary, before storage. When the beans move from storage to processing, they are cleaned further and may be dried and adowed to equdibrate at 10—11% moisture to facditate loosening of the seed coat or hud. They are then cracked. 

Annatto Extract. The aimatto tree (Bixa orelland) is a large, fast-growing shmb cultivated in tropical climates, including parts of South America, India, East Africa, and the Caribbean. The tree produces large clusters of brown or crimson capsular fmit containing seeds coated with a thin, highly... 

Miyamoto et al. (101) obtained four fractions from the seed coats of wheat which inhibited development of the wheat embryo. A component from one of the fractions responsible for 20% of the total inhibitor activity was crystallized but not identified. 

Yoshida, K. et al., Stmctural analysis and measurement of anthocyanins from colored seed coats of Vigna, Phaseolus, and Glycine legumes, Biosci. Biotech. Biochem., 60,589, 1996. 

Choung, M.-G. et al., Isolation and determination of anthocyanins in seed coats of black soybean (Glycine max (L.) Merr.), J. Agric. Food Chem., 49, 5848, 2001. 

Strack, D. et al., Cyanidin 3-oxalylglncoside in orchids, J. BioscL, 41, 707, 1986. Choung, M.-G. et al.. Isolation and determination of anthocyanins in seed coats of black soybean (Glycine max (L.) Merr.), J. Agric. Food Chem., 49, 5848, 2001. Covey, T., Analytical characteristics of the electrospray ionization process, in Biochemical and Biotechnological Applications of Electrospray Ionization Mass Spectrometry, ACS Symposium Series, Snyder, A.P. and Anaheim, C. A., Eds., Washington, D.C., 1995, chap. 2. 

Thousands of polyphenols from fruits (grapes, apples, etc.), vegetables (horse beans), and teas have been identified, many having good coloring properties, especially anthocyanins and some flavonoids. Well-documented reviews discuss the coloring capacities of some polyphenols including procyanidins. - Detailed presentations of anthocyanin and flavonoid properties and analysis are included in Sections 2.3, 4.3, and 6.3. The soluble proanthocyanidins of the colored horse bean Viciafaba L. seed coats were isolated and separated by solvent partition. 

Epoxy-18-hydroxy C18 Citrus paradisi seed coat 37... 

Seed coating with extracts of mustard (Sinapis alba) and horse radish (.Amoracia lapathifolia) was shown to have high efficacy against T. caries spores but not Fusarium spp. (SpieB and Dutschke, 1991). 

Liu, L. X., and Litster, J. D., Spouted Bed Seed Coating the Effect of Process Variables on Maximum Coating Rate and Elutriation, Powder Technol., 74 215-230 (1993b)... 

Procedure Germination conditions were 25 1°C under continuous fluorescent light of 25 mE m 2 sec-1. Seed germination was monitored by observing the seeds directly in the Petri dishes with a stereomicroscope. They were considered germinated, when the radicle had protruded through the seed coat. Seeds sampled at different times after the beginning of imbibition were used for microscopy studies. 

II. Scanning electron microscopy of radish seeds For scanning electron microscopy (SEM) observations, seed coats and endosperms were fixed in 3% glutaraldehyde in 0.065 M phosphate buffer (pH 7.4) for 2 h at... 

Fig. 4 Graphic showing the structural features of a seed coat and endosperm of a radish seed, according to Vaughan and Whitehouse (1971). e, epidermis p, palisade pi, pigment layer al, aleurone layer hi, hyalin layer. 

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