Effects of different plant oils (soybean oil, corn oil, olive oil, peanut oil, linseed oil, and cotton seed oil) and oil component emulsions on scald development in `Delicious' apples were studied. Prestorage treatment with commercial plant oils reduced scald development, but was not as effective as 2000 mg•L-1 diphenylamine (DPA) after 6 months of cold storage. Different oil components played different roles in affecting scald. At 6% or 9% concentrations, neutral lipids (mono-, di-, and tri-acylglycerols), and phospholipids inhibited scald to the same level of 2000 mg•L-1 DPA treatment. Free fatty acids partially reduced scald, while α-tocopherol at 3% or higher concentrations accelerated scald development. There were no differences in scald inhibition between unsaturated neutral lipids and saturated neutral lipids or among the different acylated neutral lipids. When α-tocopherol was stripped from plant oils, the stripped plant oils at 6% or 9% controlled scald to the same level of 2000 mg•L-1 DPA treatment. Emulsions of 6% or 9% neutral lipids, phospholipids, or stripped plant oils did not induce greasiness on fruit skin. Fruit treated with lipids, phospholipids, or stripped plant oils looked greener and fresher compared with the control by the end of storage.
Altered metabolism of membrane lipids has been proposed as a mechanism for the beneficial effects of postharvest calcium treatment on apple quality. A previous study showed that after transfer of apples stored 6 months at 0C to 20C, calcium-treated fruit exhibited slower loss of galactolipid and altered levels of sterol conjugates. The present study of lipids in “control” fruit was conducted as a prelude to further in-depth analyses of the effects of postharvest calcium and heat treatments on lipid metabolism in apples during and after cold storage. Neutral lipid, glycolipid (GL), and phospholipid (PL) fractions were obtained by column chromatography followed by TLC separation of GL and PL classes. The major GL were steryl glycosides (SG), acylated steryl glycosides (ASG), cerebrosides (CB), and mono- and digalactosyl diacylglycerols. Phosphatidylcholine (PC) > P-ethanolamine (PE) > P-irositol (PI) were the major PL. The fatty acids of PC and PE were quite similar, whereas those of PI were more saturated. CB included only 2-hydroxy fatty acids. Among the steryl lipids, free sterols > SG > ASG, with beta-sitosterol >90% of the total sterol in each.
Lipid composition and pigment content in bell pepper fruit that were freshly harvested, chilled 2 weeks at 2C (CH), or chilled then rewarmed to 20C for 4 days (RW), were determined. There was slight to moderate loss of glycerolipids during chilling, with much greater losses after rewarming. Loss of galactolipid (GL) exceeded that of phospholipid (PL). The ratio of the GL, MGDG:DGDG, did not change in CH and RW fruit, and there was no loss of chlorophyll or change in the Chl a:b ratio, but neutral carotenes declined ca 30 % after rewarming. Only small changes in total membrane sterols (TMS) were noted in CH and RW fruit, but major changes in sterol glycosylation and esterificatian occurred. The stigmasterol:sitosterol ratio increased during chilling and after rewarming. Due to PL loss, the ratios of TMS and cerebrosides to PL increased sharply in RW fruit. The ratio of 18:2 to 18:3 declined with chilling and with rewarming in all acyl lipids, but total unsaturation increased only in GL. These results indicate that most membrane damage occurs after rewarming and that the chloroplasts are especially chilling sensitive.
Abstract
Cashew (Anacardium occidentale L.) nut neutral lipids, glycolipids and phospholipids were isolated by silicic acid column chromatography. Each lipid class had characteristic fatty acid distributions with phospholipids being higher in palmitic and oleic acids, and glycolipids being higher in lin oleic acid. Comparative esterification methods indicated that cashew apple juice contained significant amounts of free lauric acid. Oleic and linoleic acids occur in almost identical, amounts in cashew nut testa whereas oleic acid predominates in the kernel. Comparison of fatty acid distributions in pulp and peel from red and yellow cultivars of cashew apple at immature and mature stages shows some differences, with notable increases in oleic acid during maturation and decreases in linoleic and linolenic acids.
Tapetum: Regulation and role in sporopollenin biosynthesis in Arabidopsis Plant Mol. Biol. 83 165 175 Liu, R.S. Qiu, Y.L. Wei, D.M. Liu, H.H. Zhu, X.Y. Tian, H.Q. Teixeira da Silva, J.A. 2012 Distribution of starch and neutral lipids in the developing
uptake of compounds is based on uptake by plant roots and the major chemical properties are lipophilicity, electrical charge, molecular weight, and H-bonding capacity. Lipophilicity is a measure of the affinity of compounds for the lipid phase of plant
were kept under control by hand-weeding. In both years, regular cultural practices were applied uniformly through all plots. Water obtained from the groundwater was used in irrigations. The irrigation water with the pH value (7.46) close to neutral, and
Figure 2B . Pollenkitt is the most striking pollen surface coat of many insect- as well as wind-pollinated species ( Weber, 1996 ). It mainly comprises neutral lipids, including carotenoid pigments ( Pacini and Hesse, 2005 ). Fig. 2. Transmission electron
determined based on the glucose equivalents. Root system analysis. Root balls were excavated from the pot, rinsed free of media, and then placed in 0.5 g·L −1 neutral red dye solution (Sigma Aldrich Co.) for 24 h at 6.7 °C. Following the dying process, roots
lipid peroxidation, resulting in an increased mass loss ( Song et al., 2009 ). Firmness. The firmness of ‘Maluma’ avocado fruit was significantly ( P ≤ 0.01) affected by the interaction between storage time and coatings. This could be explained by the