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Linoleic acid (18:2n-6) and [alpha]-linolenic acid (18:3n-3) are polyunsaturated fatty acids that are essential for mammalian nutrition, because mammals lack the desaturases required for synthesis of [DELTA]12 (n-6) and n-3 fatty acids. Many plants can synthesize these fatty acids and, therefore, to examine the effects of a plant desaturase in mammals, we generated transgenic pigs that carried the fatty acid desaturation 2 gene for a [DELTA]12 fatty acid desaturase from spinach. Levels of linoleic acid (18:2n-6) in adipocytes that had differentiated in vitro from cells derived from the transgenic pigs were [approximately equal to]10 times higher than those from wild-type pigs. In addition, the white adipose tissue of transgenic pigs contained [approximately equal to]20% more linoleic acid (18:2n-6) than that of wild-type pigs. These results demonstrate the functional expression of a plant gene for a fatty acid desaturase in mammals, opening up the possibility of modifying the fatty acid composition of products from domestic animals by transgenic technology, using plant genes for fatty acid desaturases.

We investigated the digestion of cerebrosides of plant origin prepared from maize, focusing especially on the digestive fates of trans-4, cis-8- and trans-4, trans-8-sphingadienine, which are common in higher plants. In the small intestinal mucosa and cecal contents of rats, the cerebrosidase activity at pH 5.2 toward the glucosyl linkage in maize cerebrosides (glucosylceramides) was similar to that in cerebrosides of mammalian origin. Similarly, the ceramidase activity toward the amide linkage in ceramides prepared from maize cerebrosides at pH 7.0 was the same as that toward ceramides of mammalian origin. In addition, maize cerebrosides were hydrolyzed to ceramide and free sphingoid bases in the digestive tract of rats after oral administration. To further evaluate the uptake by enterocytes of 4,8-sphingadienine, we used differentiated Caco-2 cells, derived from human colonic carcinoma, as a model of intestinal epithelial cells. The accumulation of sphingoid bases in Caco-2 cells incubated with each isomer of sphingadienine was lower than that after incubation with sphingosine (P < 0.05). Verapamil, a P-glycoprotein inhibitor, increased the accumulation of each sphingadienine but not of sphingosine, suggesting that the efflux of sphingadienine of plant origin, but not sphingosine of mammalian origin, was affected by P-glycoprotein. The digestibility of maize cerebrosides appears similar to that of cerebrosides of mammalian origin, but the metabolic fate of sphingoid bases of plant origin within enterocytes differs from that of sphingosine. Isomers of 4,8-sphingadienine degraded from dietary plant cerebrosides appear to be poorly absorbed from the digestive tract. KEY WORDS: * Caco-2 cells * ceramide * cerebroside * sphingadienine * sphingolipids

Synthesis of Alpha double prime-Fe16N2 films using reactive plasma was examined by conventional sputtering and plasma evaporation, respectively. Under controlled plasma (T(sub e)=0.2 approximately 0.6eV, N(sub e) is approximately equal to 10 to the ninth power cm to the -3) Alpha double prime-Fe16N2 films were synthesized on MgO single crystal substrates with film thickness ranging from 0.03 to 1 micrometer for sputtering and 0.2 micrometer for plasma evaporation. Deposition rate was 200 angstrom/min for sputtering and 100 approximately 420 angstrom/min for plasma evaporation. Sigma(sub S) for Alpha double prime-Fe16N2 films fabricated by plasma evaporation showed 235 emu/g and for the sputtered films showed 218 emu/g. These values are very small compared to the earlier reported value, 2.9T (310emu/g). The effects of ordering of N atoms in b.c.t. lattice and volume effect of unit cell are discussed in connection with Sigma(sub S).

Oleanolic acid (OA) and ursolic acid (UA) are natural triterpenoids that have preventive properties such as anti-tumor and anti-hepatitis activities. These triterpenes are known to exist in several medicinal plants and fruit skins. Dried fruits are usually eaten without removing the skin; thus, they may be good resources for oral intake of OA and UA. HPLC analysis of OA and UA contents in a variety of dried fruits showed that raisins contained higher levels of OA than the other fruits investigated, with green raisins containing the highest levels (79.0 mg/100 g). While raisins were found to contain only OA, dried cranberries, blueberries and cherries were shown to contain both OA and UA. The highest level of UA (65.9 mg/100 g) was detected in cranberries, which also exhibited relatively high OA levels (17.8 mg/100 g). Thus, raisins and dried cranberries can be used as rich sources of OA and UA. [ABSTRACT FROM AUTHOR]

Maize grain hardness influences storage pest resistance, a key characteristic valued by smallholder farmers. The structural changes in the endosperm determine grain hardness and are influenced by agronomic practices. The purpose of this study was to establish whether supply of calcium and magnesium based fertilizers can alter physicochemical properties of local and hybrid maize varieties and reduce the infestation by larger grain borer (Prostephanus truncatus (Coleoptera: Bostrichidae)) during storage. Two local and one hybrid maize varieties commonly grown by smallholder farmers in Malawi were cultivated under three fertilizer treatments (NPK (nitrogen, phosphorous, potassium), NPK plus gypsum, and NPK plus dolomite). After harvest, the grains were classified into flint and dent types, followed by P. truncatus infestation and determination of their physicochemical properties. The addition of gypsum and dolomite fertilizers led to higher levels of amylose, total zein and β-14 zein, traits associated with kernel hardness, compared to the application of NPK fertilizer. Moreover, local maize varieties showed higher resistance to P. truncatus infestation, hardness and biochemical properties associated with hardness (total zein, α-19 and β-14 zein, starch lysophosphatidylcholine, and non-starch free fatty acid) compared to hybrid variety. Our study suggests the potential for utilizing Ca and Mg nutrition in maize to improve kernel hardness, thus adoption of gypsum and dolomite by smallholder farmers may be beneficial against P. truncatus during storage. [ABSTRACT FROM AUTHOR]

Focuses on increased levels of policosanol and very long-chain fatty acids in potato pulp fermented with Rhizopus oryzae. Discovery of significant amounts of policosanol and very long-chain fatty acids ranging in carbon length from 22 to 30 in the lipophilic fraction obtain from potato pulp fermented with Rhizopus oryzae; Assertion that these compounds would have originally been present as suberin-related compounds in the periderm of potato tubers and concentrated into potato pulp during the process of starch production; Suggestion that the policosanol and VLFAs extracted from potato pulp with organic solvents have increased after fermentation.

Linoleic acid (18:2n-6) and α-linolenic acid (18:3n-3) are polyunsaturated fatty acids that are essential for mammalian nutrition, because mammals lack the desaturases required for synthesis of Δ;12 (n-6) and n-3 fatty acids. Many plants can synthesize these fatty acids and, therefore, to examine the effects of a plant desaturase in mammals, we generated transgenic pigs that carried the fatty acid desaturation 2 gene for a Δ12 fatty acid desaturase from spinach. Levels of linoleic acid (18 : 2n-6) in adipocytes that had differentiated in vitro from cells derived from the transgenic pigs were &ap; 10 times higher than those from wild-type pigs. In addition, the white adipose tissue of transgenic pigs contained &ap; 20% more linoleic acid (18:2n-6) than that of wild-type pigs. These results demonstrate the functional expression of a plant gene for a fatty acid desaturase in mammals, opening up the possibility of modifying the fatty acid composition of products from domestic animals by transgenic technology, using plant genes for fatty acid desaturases. [ABSTRACT FROM AUTHOR]

Sphingolipids are ubiquitous compounds derived from ceramide that consist of a sphingoid long-chain base with a 2-amino group amide linked to fatty acid and are present in the membranes of many organisms. As a principal sphingolipid, Saccharomyces cerevisiae contains a free ceramide and its inositol-phosphorylated derivatives (acidic types) but not a neutral glycosylated ceramide, glucosylceramide (cerebroside), which usually appears in eukaryotic cells. When 31 strains accepted in the genera Saccharomyces, Torulaspora, Zygosaccharomyces, and Kluyveromyces were analyzed for sphingolipids, cerebrosides were found in S. kluyveri, Z. cidri, Z. fermentati, K. lactis, K. thermotolerans, and K. waltii. The cerebrosides of S. kluyveri and K. lactis included 9-methyl 4-trans, 8-trans-sphingadienine and its putative metabolic intermediates. A unique characteristic of S. kluyveri was the presence of a trihydroxy sphingoid base, which rarely occurs in fungal cerebrosides. A polymerase chain reaction with primers targeted to the glucosylceramide synthase gene of other microorganisms amplified the fragments of the expected size from S. kluyveri and K. lactis and further extended to the adjacent regions. The presumed protein of S. kluyveri had 54.4% similarity to that of K. lactis, higher than the glucosylceramide synthases from Candida albicans, Pichia pastoris, and other organisms. From these observations, the divergence of S. kluyveri from the lineage of K. lactis in their evolution is discussed. [Copyright &y& Elsevier]

Glucosylceramide (GlcCer), a major sphingolipid in plants, possesses various food functions, including improvement of intestinal impairments. This study evaluated rice cooking conditions and cultivars based on GlcCer levels transferred into the digestive juice using an in vitro digestion model to investigate the factors related to GlcCer availability. GlcCer levels transferred into the digestive juice were higher in rice gruel than in boiled rice. The GlcCer levels in the digestive juice of boiled rice varied based on the rice cultivar, whereas those in rice gruel had no difference. Thus, GlcCer in rice was not fully utilized via digestion. Further, bioaccessibility was related to the amylose ratio and added water content.

Perilla oil is a valuable food source of α-linolenic acids. However, its high reactivity with oxygen shortens its shelf-life after opening. This study investigated the antioxidative profiles of 15 plant materials, including herbs, and examined methods to suppress the oxidation of perilla oil using these plant materials. These plant materials had wide ranges of phenolic, carotenoid, and chlorophyll contents. They exhibit radical scavenging activities and suppress lipid peroxidation, which show highly positive correlations with the phenolic contents. Dipping most of the plant materials examined in perilla oil suppressed its oxidation, and the peroxide values of the oil mixtures indicated a negative correlation with the carotenoid and chlorophyll contents of the plant materials. The leaves of Angelica, Astragalus, and Thyme herbs exhibited the same effect as that of ascorbyl palmitate, which was used as a positive control after 8 wk of incubation in the dark. The suppression of lipid peroxidation was found to be related to the herbal contents of carotenoids and chlorophylls, rather than phenols. Hence, herbal leaves can suppress the oxidation of perilla oil in the dark. The oxidation of n-3 polyunsaturated fatty acids could be suppressed effectively by utilizing plant materials with abundant carotenoids and chlorophylls.