Plant cuticles contain mainly lipid polymers (cutin), protecting them against desiccation and environmental stresses. The monomeric composition of the cuticular polymer fractions of three cereal fibers: maize bran, wheat bran and sorghum bran, as well as hemicellulose/cellulose fractions isolated from sorghum bran were investigated and compared with cuticular content isolated from apple and tomato peel samples. Total cuticular contents in apple and tomato peels were the highest, ranging from 54.5 % to 54.8 %, when compared with the total cuticular content of maize, wheat and sorghum brans. Among three cereal samples, the cuticular material content in sorghum bran (7.14%) was higher than the maize bran and wheat bran (3.92% and 5.92% respectively). The hexadecanoic acid (C16), octadecanoic acid (C18), ω-hydroxy fatty acids, with medium chain functional groups such as enoic, epoxy and hydroxyl groups were identified in each cutin sample. The percentage of p-coumaric acid in apple and tomato peel samples were 84.0% and 78.7% respectively of the total phenolic acids present. The ferulic acid content in maize, sorghum and wheat brans were 94.1%, 92.8% and 88.0% respectively, indicating that ferulic acid was the major phenolic compound in these brans.

Two methyl-branched triesters, trimethylolpropane-triisostearate (TMP-ISA) and trimethylolpropane-triisooleate (TMP-IOA) have been synthesized via esterification of trimethylolpropane with isostearic-acid and isooleic-acid, respectively. Isostearic-acid and isooleic-acid have been previously produced through the skeletal-isomerization reaction of naturally derived oleic acid using a reusable zeolite catalyst. TMP-ISA and TMP-IOA are characterized by FTIR NMR, GC-MS, and LC-MS. Physicochemical and tribological analysis reveal that TMP-ISA and TMP-IOA exhibit higher oxidative stability, viscosity index, anti-wear property, and better cold flow properties when compared to high-oleic sunflower oil or polyalphaolefin, a common lubricant base oil. Lubricant property analysis of blends of TMP-ISA or TMP-IOA with high-oleic sunflower oil or polyalphaolefin demonstrates their miscibility and potential applications as biolubricants. Upon commercialization, these developed bio-based esters have the potential to reduce the existing reliance on non-renewable petroleum based lubricants. Practical application: Methyl-branched triesters with trimethylolpropane backbone exhibit promising physicochemical and tribological properties to be used as bioingredients in bioproducts.

Brown rice is nutritionally superior to white rice, yet oil rancidity can be problematic during processing and storage regarding sensory attributes. Germinating brown rice is known to generally increase some health-promoting compounds. In response to increasing the consumption of plant-based beverages, we sprouted unstabilized brown rice, using green technologies and saccharification enzymes for value-added beverages. ‘Rondo’ paddy rice was dehulled, sorted and germinated, and beverages were produced and compared against non-germinated brown and white brewers rice beverages. The preliminary germinated brown rice beverage contained significantly higher concentrations of total lipids, diacylglycerols, triacylglycerols, free sterols, phytosterol esters and oryzanols than both non-germinated brown and white rice beverages. White rice beverages had significantly higher free fatty acids. Significant lipid losses occurred during sieving, yet novel germinated brown rice beverages contained appreciable levels of valuable health-beneficial lipids, which appeared to form natural emulsions. Further pilot plant investigations should be scaled-up for pasteurization and adjusted through emulsification to ameliorate sieving losses.

The lipids and phenolic compounds of wheat bran (WB) and hemicellulose B (water extractable Hemi. B and alkali extractable Hemi. B) fractions from four wheat varieties were investigated. The X-ray diffraction pattern and NMR spectra of those Hemi. B were also studied. The predominant lipid components identified in WB include triacylglycerols (41.58?53.24 wt %) and free fatty acids (7.62?13.85 wt %) with the highest content in HD-2967 and C-306 varieties (9.13 and 13.85 wt %, respectively). The WE-Hemi. B had more lipids than the AE-Hemi. B fractions. The HD-3086 variety had the highest lipid content in both its WE-Hemi. B and AE-Hemi. B fractions (6.60 and 3.19 wt %, respectively). The bound phenolic content in WB was higher (1160?2848.88 ?g GAE/g) than free phenolic content (564.17?724.72 ?g GAE/g). The total antioxidant activity (TAA) of WB varied from 11.76 to 13.01 ?mol TE/g. The bound protocatechuic and ferulic acids were the major phenolic acids with the highest content in WB of HS-490 and HD-2967 variety, respectively. The major flavonoid identified in WB was bound catechin (70.98?198.58 ?g/g) with the highest content in HD-2967. The ferulic acid was quantified as the major phenolic acid in Hemi. B fractions with a significantly higher level in WE-Hem-B (439.0?627.0 ?g/g) compared to AE-Hemi. B (5.7?13.0 ?g/g) fractions. The level of syringaldehyde varied from 0.8 to 1.4 ?g/g in AE-Hemi. B while p-coumaric acid content in AE-Hemi. B and WE-Hemi. B varied from 0.2 to 0.3 and 5.8?9.7 ?g/ g, respectively. Sinapic acid and syringaldehyde were detected only in WE-Hemi. B fractions of HD-2967 and C306 varieties. The X-ray diffractograms of WE-Hemi. B and AE-Hemi. B showed an amorphous profile with a broad peak in the region of 2? 15?23?. The structural elucidation of Hemi. B by 1H NMR analysis indicated the xylose backbone with substitution mainly at C(O)-3 and/or C(O)-2 positions by arabinose residues and presence of esterified ferulic acid residues attached to arabinose side chains.

Sorghum wax can be extracted from the surface of sorghum (Sorghum bicolor) kernels. It is composed mostly of a mixture of unsaturated C(28)and C(30)alkanes, fatty acids, fatty alcohols, and fatty aldehydes. Like carnauba wax, sorghum wax is a hard wax with a high melting point and it has potential edible and industrial applications. The yield of sorghum wax from the surface of sorghum kernels is 0.2-0.5 g of wax per 100 g of kernels. Sorghum wax can also be recovered from the "distillers oil" which is obtained after fermentation of sorghum (milo) or sorghum/corn blends in dry grind fuel ethanol plants. This distillers sorghum wax can potentially be obtained in yields of up to 10% by chilling the distillers oil to precipitate the wax and then recovering it via centrifugation or filtration. Like sorghum kernel wax, distillers sorghum wax is mainly composed of C(28)and C(30)alkanes, alcohols, and aldehydes in the molecular weight (MW) range of 350-450. However, we found that 7-49% w/w of distillers sorghum wax is composed of larger wax components with MW of 799-912. Analysis via high-resolution atmospheric pressure chemical ionization mass spectrometry (APCI) and gas chromatography with electron ionization mass spectrometry (GC/MS-EI) resulted in exact mass data and fragmentation patterns that suggested that these high MW compounds are monounsaturated fatty aldehyde dimers, likely formed by aldol condensation. Further confirmation supporting the GC/MS data for the aldol reaction was obtained by comparison with similar aldol products.

Recovered hemicellulose fractions from biorefineries have the potential to improve overall process economics during the production of biofuels or other high value chemicals. A common hemicellulose found in many agricultural feedstocks is arabinoxylan (AX). This work investigated the influence of ferulic and p-coumaric acids on the antioxidant capability of AX hemicellulose recovered from sorghum bran, biomass, and bagasse. Sorghum bagasse and sorghum biomass AX contained the largest quantities of bound ferulic and p-coumaric acids at 13.1 mg/100 g and 6.3 mg/100 g, respectively. Antioxidant performance showed that sorghum bagasse AX hemicellulose produced the best reducing capability, while sorghum biomass and sorghum bran AX hemicellulose performed better as free radical scavengers. A reduction in free radical scavenging, as determined by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, occurred for sorghum bagasse and sorghum biomass AX hemicellulose at higher polysaccharide concentrations, which was either caused by the solution properties of the AX hemicelluloses or DPPH reaction reversibility in the presence of phenolic compounds with methoxy content. Alternatively, H2O2 scavenging by the AX hemicellulose revealed a dose-dependent response. Although scavenging effect was reduced at higher concentrations, sorghum bagasse AX hemicellulose functioned as having the best antioxidant capacity with respect to total reducing capability.

Commercial waxes are difficult to analyze due to their limited solubility in most organic solvents. Recently, our laboratory published a new reverse phase HPLC-MS method using a C30 column, a gradient of methanol and chloroform, an evaporative light-scattering detector (ELSD), and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) to analyze jojoba wax (jojoba oil), carnauba wax, and sorghum wax. In the current study, the published HPLC method was modified by reducing the solvent gradient program to 60minutes and this new method was evaluated for its usefulness for the analysis of five other commercial waxes (beeswax, rice bran, sunflower, candelilla and paraffin waxes). The ELSD appeared to detect all types of wax components, whereas the APCI-MS was most useful for the identification of wax esters and was unable to detect hydrocarbons, such as those in candelilla wax and paraffin wax. Previous HPLC methods for waxes and most GC methods for waxes only separate wax esters with size up to 54 carbons (C54) but this method was able to separate those with size up to 60 carbon wax esters. This report presents the first HPLC chromatograms for rice bran, sunflower, candelilla, and paraffin waxes. The main contribution of this work is the evidence that a C30 reverse phase HPLC system provides acceptable chromatographic separation of major components in commercial waxes. [GRAPHICS] .

Background and objectivesDecortication of sorghum grain separates its pericarp (bran) from the endosperm which could have beneficial impacts on ethanol production while producing value-added coproducts. The goal of this study was to compare three bench-scale devices (barley pearler, scarifier, and rice polisher) to decorticate sorghum grain and analyze the composition of each fraction. FindingsThe scarifier and barley pearler produced bran with similar contents of protein (similar to 10%), starch (similar to 40%), and total dietary fiber (similar to 40%). In a single batch to produce 10% (w/w) bran, the scarifier processed more sorghum to produce more bran (12g/150g) than the barley pearler (7g/75g). The rice polisher produced bran (43g/500g) with higher content of oil (similar to 12%), protein (similar to 11%), ash (similar to 6%), and starch (similar to 47%), but total dietary fiber was lower (similar to 29%). The scarifier bran had the highest wax content (1.9%), while the rice polisher and barley pearler brans had similar lower wax content (1.6%). ConclusionsThe composition of bran from the rice polisher indicated that more germ and some endosperm were removed during decortication as compared to the other devices. Significance and noveltyThere is a need for producing bran between laboratory- and pilot-scale with efficient separation of the pericarp from the endosperm. This research is the first to compare the composition of all sorghum fractions, including a wax analysis, from three types of bench-scale decortication devices.

Sorghum has potential as a domestic source of wax for applications in the food and nonfood industries. The waxes extracted from sorghum have similar physical properties to those of Carnauba wax, a common imported commercial wax. This work focused on the extraction, fractionation, and characterization of waxes from sorghum kernels. Extraction was performed by varying the extraction conditions including temperature and solvents (hexane, ethanol, and methanol). A fractionation technique was developed to separate and quantify waxes from nonwaxes. The fractions were then characterized using a reverse-phase high-performance liquid chromatography method developed in our laboratory that utilizes an evaporative light-scattering detector for quantification. The results showed that the average amount of wax extracted from the surface of intact sorghum kernels was about 0.3 wt% using hexane at temperatures between 25 and 120 degrees C and 1000 psi. The yield of wax via hexane extraction increased with temperature and ranged from about 0.06 to 0.39 wt%. Extraction with alcohols resulted in higher yields of extracts, but after fractionation to remove nonwax components, the yield of waxes was reduced by 31% for ethanol and 47% for methanol compared to hexane.

Biodiesel production in the U.S. from vegetable oils has increased substantially during the past decade. However, its further increase is limited by the low amounts of oil produced per hectare from temperate oilseed crops. Recently novel transgenic sugarcane has been developed to accumulate both sugars and lipids in stems, making it a promising dual-purpose feedstock to produce both ethanol and biodiesel. In this study, two lines of the transgenic lipid producing sugarcane (lipid-cane) and the non-transformed sugarcane were characterized and processed. The total lipid concentrations were 0.7%, 0.9% and 1.3% for the non-transformed sugarcane and lipid-cane lines19B and 25C, respectively. Lipid composition analysis showed that about 31–33% of the total lipids were triacylglycerols, main feedstock for biodiesel production, for the lipid-cane samples, while this value was only 5% for the non-transformed sugarcane. By processing the sugarcane stems with a juicer, about 90% of the sugars and 60% of the lipids were extracted with juice. The extracted sugars in juice were fermented to ethanol and the lipids were later recovered from the fermented juice using organic solvents. The recovered lipids from the fermented juice were 0.3, 0.5 and 0.8g/100g dry stem for the non-transformed sugarcane and lipid-cane lines 19B and 25C, respectively. This study proved the concept of the lipid and sugar coproduction from the novel lipid-cane, which have a potential to make a large-scale replacement of fossil derived fuel without unrealistic demands on land area.

Sorghum is a genus of plant in the grass family, which is used for both grain and forage production throughout the world. In the United States, sorghum grain is predominantly used as livestock feed, and in ethanol production. In recent years however, sorghum grain has been investigated for other industrial applications, including gluten free food sources for the US food market, and waxes. The United States is the world's largest producer of grain sorghum, which is grown in the arid regions of the southern Great Plains, Arizona and California.Carnauba wax is used in a variety of products; including cosmetics, industrial polishes, food products, and paper products. The United States has no domestic source of carnauba wax, and imports 100% of its carnauba wax supply. Sorghum wax has demonstrated similar physical properties to carnauba wax, and could potentially be a viable substitute for carnauba wax.In this paper we present the first successful reversed phase HPLC method, via a C30 column, for the analysis and characterization of waxes, without the need for specialized columns or sample derivation. Sorghum wax is composed of a heterogeneous mixture of compounds, dominated by C28 and C30 saturated and unsaturated species, while carnauba is more homogeneous in nature, and composed primarily of C56-C60 saturated wax esters. (C) 2016 Published by Elsevier B.V.

Carotenoids are potentially valuable components in grain sorghum and there is a need to better understand their concentration, composition, and value. Thirteen modern commercial grain sorghum hybrids and five sorghum lines were extracted and analyzed and the levels of oil and carotenoids were compared. The same samples were also evaluated for lipolytic enzyme activity. The oil content in all eighteen samples ranged from 3.21 to 4.29 wt%. Lutein and zeaxanthin were the predominant carotenoids and the levels of total carotenoids ranged from 3.82 to 19.5 ppm in the oil, which was much lower than the levels of total carotenoids in two yellow corn samples (70.8 and 103 ppm). Lipolytic enzyme activity was estimated by storing milled kernel samples for 2 weeks at 25 °C and measuring the levels of total free fatty acids. After 2 weeks, the levels of free fatty acids in the oil of the eighteen sorghum samples ranged from 11.49 and 52.17 wt%, compared to 10.29 and 17.54 wt% in oil from the two corn samples. This new data will be useful for persons using grain sorghum for food, biofuels and other industrial applications. Examples of sorghum genotypes with high and low levels of carotenoids and high and low levels of lipolytic enzymes were both identified.

Publisher Summary This chapter discusses the two lesser-known types of corn oil that have received much attention in recent years, corn kernel oil and corn fiber oil. The sequential extraction process was developed for the production of corn kernel oil and it involves the flaking of corn before ethanol extraction. The grinding (milling) of corn fiber is recommended for the production of corn fiber oil to a particle size of 1 micron (20 mesh) or smaller before beginning hexane extraction to achieve optimal oil yields. Both corn kernel oil and corn fiber oil contain unique health-promoting components that are lacking in commercial corn oil, which is obtained by extracting corn germ. Corn kernel oil contains very high levels of lutein and zeaxanthin; a regular consumption of it may prevent the onset of age-related macular degeneration. Corn fiber oil contains the highest levels of phytosterols of any known natural oil or extract and a regular consumption of it may reduce the levels of serum LDL- and total cholesterol.

An aqueous enzymatic method was developed to extract corn oil from corn germ. The basic steps in the method involved “churning” the corn germ with various enzymes and buffer for 4 h at 50°C, and an additional 16 h at 65°C, followed by centrifugation and removal of the oil layer from the surface. No hexane or other organic solvents are used in this process. By using oven-dried corn germ samples (6 g) from a commercial corn wet mill, corn oil yields of about 80% were achieved using three different commercial cellulases. A fourfold scale-up of the method (to 24 g of germ) resulted in oil yields of about 90%. Nine other commercial enzymes were evaluated and resulted in significant but lower oil yields. In the absence of enzymes, oil yields of 27 to 37% were achieved. The chemical compositions of hexane-extracted vs. aqueous enzymatic-extracted corn oils were very similar.

Plant sterols (phytosterols) have been shown to possess serum cholesterol-lowering properties. In recent years, several phytosterol-enriched functional food products have been developed and marketed. Some phytosterol products contain common unsaturated sterols and some contain a subset of phytosterols called phytostanols (saturated sterols, also called plant stanols). Current methods for the quantitative analysis of plant sterols are labor intensive and require sophisticated gas or liquid chromatographs. In this study, a popular commercial spectrophotometric serum cholesterol test kit was evaluated for the analysis of plant sterols. The results indicate that the method could be modified to analyze phytosterols and phytostanols by increasing the incubation time. Both free phytosterols and fatty acyl phytosteryl esters were quantitatively analyzed, but ferulate phytosteryl esters, such as those that are found in corn and other cereals, were not hydrolyzed by the enzymes in the test kit and therefore were not detected.

Samples of freshly ground corn kernels and freshly ground rolled oats were extracted via pressurized liquid extraction (accelerated solvent extraction) using four different organic solvents [hexane, methylene chloride (also known as dichloromethane), isopropanol, and ethanol] at two temperatures (40 and 100°C). Lipid yields varied from 2.9 to 5.9 wt% for ground corn and from 5.5 to 6.7 wt% for ground oats. With ground corn, more lipid was extracted as solvent polarity was increased, and for each individual solvent, more lipid was extracted at 100°C than at 40°C. With ground oats, the same temperature effects was observed, but the solvent polarity effect was more complex. For both corn and oats, methylene chloride extracted the highest levels of each of the nonpolar lipid classes. In general, for both corn and oats, icnreasing solvent polarity resulted in increasing yields of polar lipids, and for each solvent, more of each lipid class was extracted at 100°C, than at 40°C. Among the lipids in corn extracts, the phytosterols may be the most valuable, and total phytosterols ranged from about 0.6 wt% in the hot ethanol extracts to about 2.1 wt% in the hot hexane and methylene chloride extracts. Total phytosterols in all oat extracts were about 0.1 wt%. Digalactosyldiacylglycerol was the most abundant polar lipid in the oat extracts; its levels ranged from 1.6 wt% in the cold hexane extracts to 4.3 wt% in the hot ethanol extracts.

Dry-milled yellow corn and freshly ground food and nonfood grade yellow and white hybrid corn kernels were pretreated in a solution of lactic acid and sodium metabisulfite followed by extraction with 70% ethanol. Zein was precipitated from the extract by reducing the ethanol content of the extract to 40%. Lipid associated with the zein isolates was between 15 and 20% and contained mostly endogenous free fatty acids. The effect of the endogenous free fatty acids on zein isolate films, with and without free fatty acids, was determined by measuring various film properties. Stress-strain measurements indicated 40-200% greater elongation for zein films containing endogenous free fatty acids. Films prepared from zein isolated from preground corn stored for approximately 4 months (27 degrees C, 17% relative humidity) had approximately 3 times greater elongation values than zein films prepared from freshly ground corn.

Previously, hexane extraction of corn fiber was reported to produce a unique and potentially valuable oil that contained high levels of several phytosterols (which have been noted for their cholesterol-lowering properties). Current studies revealed that heat treatment (over the range of 100-175 degrees C) of corn fiber in either a convection oven or a vacuum oven caused only a modest reduction in the levels of the phytosterol components. However, these same heat pretreatments caused a considerable increase (up to 10-fold) in the levels (increasing from 0.34 wt % to a maximum of 3.64 wt % gamma-tocopherol in the oil) and yields (increasing from 5.4 mg of gamma-tocopherol/100 g of corn fiber to a maximum of 52.1 mg of gamma-tocopherol/100 g of corn fiber) of gamma-tocopherol in corn fiber oil. The main differences between the convection oven and vacuum oven pretreatments were associated with the disappearance of free fatty acids and free phytosterols at the higher temperature pretreatments in the vacuum oven, probably due to the lower boiling points of these lipids. Microwave pretreatment was also effective but caused a much smaller increase in the levels of gamma-tocopherol.