Wheat straw compounds

With the extraction procedure we employed (22), ferulic acid was isolated as the most inhibitory component in wheat straw. There could also be other unknown compounds in the straw which would not be evident with this procedure. In addition, we ignored the possible influence of toxin-producing microorganisms. Microorganisms may have influenced the phytotoxicity exhibited by the aqueous wheat extract in Table IX. Although the present study was not concerned with the phytotoxic effects of microbially decomposed wheat straw, an influence of microbial activity on ferulic acid phytotoxicity was observed. From the results shown in Table XI, it appears that the presence of the prickly sida seed carpel enhanced the inhibitory effects of ferulic acid. In addition to ferulic acid in test solutions containing prickly sida seeds with carpels, a second compound, 4-hydroxy-3-methoxy styrene, was also found to be present. This compound is formed by the decarboxylation of ferulic acid and was produced by a bacterium present on the carpel of prickly sida seed. The decarboxylation of ferulic acid was detected in aqueous solutions of ferulic acid inoculated with the bacterium isolated from the carpels of prickly sida seed. No conversion occurred when the bacterium was not present. 

A simple lactone, parasorbic acid, from the fruit of mountain ash, inhibits seed germination and also has antibacterial action (75). Another such compound, patulin, is produced by several fungi, including Penicillium urticae, which produced large amounts of the substance when growing on wheat straw (76). 

Reversed-phase chromatography is the most popular mode of analytical liquid chromatography for phenolic compounds. In most cases, the reported systems for the separation of phenolics and their glycosides in foods are carried out on reversed-phase chromatography on silica-based Cl8 bonded-phase columns. Occasionally, silica columns bonded with C8 were applied in the analysis of phenolic acid standards and coumarins (7), and C6 columns for the analysis of ferulic acid in wheat straw (8). 

Olsson, M. (2006). Wheat Straw and Peat for Fuel Pellets - Organic Compounds From Combustion. Biomass Bioener., 30, 555-564. 

Martin, J. P. and Haider, K., 1979. Effect of concentration on decomposition of some 14C-labeled phenolic compounds, benzoic acid, glucose, cellulose, wheat straw, and Chlorella protein in soil. Soil Sci. Soc. Amer. J. 43, 917-920... 

On its own, DMD is too powerfnl an electrophilic reagent to be considered for lignin-retaining bleaching. Bnt, in carefnl conjunction with alkaline peroxide, it has been found useful in bleaching the ferulic acid-linked lignins in wheat straw mechanical pulps. Pan et al. [112] evaluated DMD for its ability to oxidize ferulic acid (IVa), ferulic acid ethyl ester and diferulic acid (IVb). All these model compounds were completely oxidized at room temperature. 

Infrared spectroscopy is an effective way to identify the presence of certain frmctional groups in a molecule. Also, one can use the unique collection of absorption bands to confirm the identity of a pure compound or to detect the presence of specific impurities [19, 20]. The FTIR spectra of wheat straw and pretreated wheat straws (Fig. 4) initially appeared rather similar. However, in a closer examination, spectra of pretreated wheat straw with water (lines 2 and 3) were similar to those of untreated wheat straw (line 1), and spectra of NaOH pretreated wheat straw (lines 4-7) can be clearly distinguished from those of untreated wheat straw (line 1) by the disappearance of ester linkage absorption (1,733 cm band). 

Biopolymers can be directly obtained [KOB 03] fiom hemicellulose in com or starch. Starch, a major polymer from arable crops, is a good candidate for the production of biodegradable packaging or objects. If combined with a compound of wheat straw, its potential apphcations could increase. 

Xylans from batch extraction are also good film formers even though the tensile properties of these films differ slightly from the twin-screw extracts. The difference might be a result of the compostion in minor compounds liable to oxidative cross linking in the twin-screw extract, thus leading to a more rigid film. Combined extrusion of wheat straw and bran leads to an extract witli a... 

Mortierella isabellina could grow on both C5 (arabinose, ribose, xylose, and mannose) and disaccharides (sucrose and cellobiose). When grown in the presence of model lignocellulosic inhibitor compounds, phenolic compounds were highly inhibitory, while furfural, 5-HMF, acetic acid, formic acid, and levulinic acid showed limited inhibition. Surprisingly acetic and formic acid improved lipid production by twofold as compared with that observed for the control. When grown on wheat straw, hydrolysate up to 53 % total lipids was obtained with a lipid yield of 16.8 % from the carbon sources (Zeng et al. 2013). 

Compound Unit (dry basis) Spruce Pine Birch Willow Wheat straw Rice straw Com stover... 

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