Oat spelts

By the treatment of oat spelt xylan with phenyl or tolyl isocyanate in pyridine the fully fimctionahzed corresponding carbamates were prepared [416]. Xylan 3,5-dimethylphenylcarbamate showed higher recognition abihty for chiral drugs compared to that of the same cellulose derivative [417]. 

Thermoplastic xylan derivatives have been prepared by in-hne modification with propylene oxide of the xylan present in the alkaline extract of barley husks [424,425]. Following peracetylation of the hydroxypropylated xylan in formamide solution yielded the water-insoluble acetoxypropyl xylan. The thermal properties of the derivative quahfy this material as a potential biodegradable and thermoplastic additive to melt-processed plastics. Xylan from oat spelts was oxidized to 2,3-dicarboxyhc derivatives in a two-step procedure using HI04/NaC102 as oxidants [426]. 

En me Treatment of LCCs. Purified Bacillus circulans xylanase (specific activity, 110 units/mg protein), purified Coriolus versicolor )9-mannanase (specific activity 179 units/mg protein), purified Thermoascus aurianticum /8-glucosidase (specific activity, 150 units/mg protein), and purified Schizophyllum commune acetyl xylan esterase (AXE specific activity, 180 units/mg protein) were used. Unit activity for xylanase and )9-mannanase was defined as the amount of enzyme catalyzing the release of 1 /xmol reducing power per minute at 50°C and pH 6.0 using oat spelts... 

Koch-Light 1887-00 oat-spelt xylan (Lot 90560) was split into soluble and insoluble fractions by dissolving it in 0.05A/, pH 6.05 sodium citrate buffer and centrifuging out Ae unAssolved material. The msoluble portion was suspended in Ae buffer in roughly 1% concentration and was assayed wiA an equal volume of Xylanase II in... 

Figure 1. Induction of xylanases in Trichoderma harzianum. The ratios of xylanase to endocellulase activities were determined in the culture filtrates of T. harzianum grown on steam treated aspenwood. Aspen chips were steam treated from 20 to 240 s at 240° C to produce a series of samples with a variable content of xylan and cellulose. The specific content of these carbohydrates were expressed as the ratio of xylan to glucan. Enzyme activities were determined on culture filtrates of 300 mL batch cultures of T. harzianum grown on these wood samples at a loading of 1% (w/v) as described by Saddler and Mes-Hartree (66). Enzyme activities were also determined in culture filtrates of T. harzianum grown on Avicel, Solka Floe and oat spelts xylan.

Cereals containing gluten (i.e., wheat, rye, barley, oats, spelt, kamut or their hybridized strains) and products thereof, except cereals used for making distillates or ethyl alcohol, wheat-based maltodextrins, and dextrose and glucose syrups... 

Variations on the filter paper assay have been developed. Irwin and coworkers have established a method for differentially measuring soluble and insoluble reducing sugars released from filter paper.192 Ghose and the IUPAC committee also proposed a similar approach for measuring hemicellulases in 1987.193 This method relies on meeting a standard level of conversion of the xylan fraction in oat spelt xylan to xylose in a specified... 

XOS are manufactured by enzymatic hydrolysis of xylan from corn cobs, oat spelt xylan or wheat arabinoxylan [257]. Xylan, a principle t)q)e of hemicellulose exists as a linear polymer of -D-xylopyranosyl units linked by 1 4 glycosidic bonds. Depending on the origin, different substituents such as arabinfuranosyl, 4-0-methylglucuronosyl and acetyl groups are present. Typical raw materials for XOS production include hardwoods, com cobs, straws. 

Tiichoderma longibrachia- tum 37.7 kDa 5.0-6.0 45 Oat spelt Xylobiose, xylotetraose and higher DP XOSs Nd... 

The microorganism was grown in mineral medium supplemented with 1.0 to 10.0 g/L of the earbon source and also in a mineral medium with oat spelt xylan or D-maltose, with the addition of glucose or xylose. Samples were collected from the culture and centrifuged at... 

Fig. 1 Effect of carbon sources concentration on xylanase production by B. circulans Dl, after 48 h of cultivation. Oat spelt xylan (squares) D-maltose (circles) D-galactose (triangles) D-glicose (inverted triangles) D-cellobiose (diamonds) D-arabinose (plus signs)...

Fig. 2 Xylanase production by B. circulans Dl in mineral medium with oat spelt xylan (10.0 g/L squares) and oat spelt xylan (10.0 g/L) plus glucose (a) or xylose (b) at 1.0 (circles), 3.0 (triangles) or 5.0 g/L (inverted triangles)...

Fig. 4 Twenty-four-hour digestions of oat spelt xylan with varying loadings of XynA presented as the percent of xylan eonverted to xylotetrose, xylo-triose, xylobiose, and xylose. All error bars represent the SD replicate assays...

Digestions of oat spelt xylan with purified XynA and the XlnD further show the utility of the 3-xylosidase activity in a real lignocellulosic system. For example, in Fig. 4, we show how the endoxylanase primarily degrades the xylan to xylobiose and xylotriose and to a lesser extent, xylose. Shown in Fig. 5, xylan converted by XynA in the presence of small quantities of XlnD is entirely converted to monomeric xylose during the 24-h incubation... 

H. jecorina Untreated Tifton 85 Shake flask 28 C, 1% oat spelt Xylan 85.0 This work... 

H. jecorina LHW- DDGS Shake flask 28°C, 1% oat spelt xylan 93.4 18... 

---