Abstract Factors that limit forage quality are complex and interactive. Structural characteristics breakdown primarily highly lignified support tissues like sclerenchyma xylem. However, the presence of chemical barriers (likely low molecular weight phenolic compounds) within “living” cell walls, such as parenchyma bundle sheath epidermis, prevents fiber degradation in these tissues. The high proportions leaves warm‐season grasses plus growth hotter climates, which tends to speed maturity,...

Sheep fed the forage Digitaria pentzii fertilized with sulfur were compared those unfertilized for rumen microbial population involved fiber degradation. No differences detected in bacterial as determined by anaerobic cultures on a habitat-simulating medium, xylan, or pectin, 35S labeling techniques protein, transmission electron microscopic studies of bacterium-fiber interactions. Rumen volume and water flow from not different sheep each forages. fungi prevalent sulfur-fertilized D. shown...

Ruminal bacteria were subjected to a series of phenolic compounds in various concentrations acquire fundamental information on the influence growth and potential limits forage utilization by monomers. Ruminococcus albus 7, flavefaciens FD-1, Butyrivibrio fibrisolvens 49, Lachnospira multiparus D-32 tested against 1, 5, 10 mM sinapic acid, syringaldehyde, syringic ferulic vanillin, vanillic p-coumaric p-hydroxybenzaldehyde, p-hydroxybenzoic hydrocinnamic acid. Responses variable dependent...

Bermudagrass (Cynodon dactylon) leaf blades and whole cordgrass (Spartina alterniflora) fiber were evaluated for degradation of cell walls by microbial groups in ruminal fluid. The selected the addition antibiotics to inoculum as follows: (i) fluid (WRF), no antibiotics; (ii) cycloheximide (C) inhibit fungi, thus showing potential bacterial activity; (iii) streptomycin penicillin (S,P) fiber-degrading bacteria, fungal (iv) streptomycin, penicillin, chloramphenicol (S,P,CAM) all bacteria...

The white rot fungi Ceriporiopsis subvermispora FP-90031-sp and Cyathus stercoreus ATCC 36910 were evaluated for their ability to delignify Bermuda grass (Cynodon dactylon) stems improve biodegradability. Compositional structural alterations in plant cell walls effected by the determined nuclear magnetic resonance spectroscopy, gas chromatography of alkali-treated residues, microspectrophotometry, electron microscopy. Contaminating bacteria fungi, which grew from unsterilized stems, did not...

Five anaerobic fungal isolates from the bovine rumen were grown on Coastal Bermuda grass (CBG) leaf blades and monitored over a 9-day period for substrate utilization, fermentation products, cellulase, xylanase activities. Two of showed monocentric growth patterns; one (isolate MC-1) had monoflagellated zoospores morphologically resembled members genus Piromyces; other MC-2) multiflagellated Neocallimastix. Three (PC-1, PC-2, PC-3) exhibited polycentric have not yet been described in...

Seven strains of filamentous fungi and one yeast were isolated from flax that was dew retted in the United States. These subcultured to purity identified, six appear not have been reported earlier as isolates dew-retted flax. Five purified U.S. strains, two Europe, a laboratory culture Aspergillus sojae tested for their ability ret stems. The monocultures evaluated degree retting, fiber strength, dry weight loss, tactile response (i.e., feel softness) reflected fiber. Structural...

Two extracellular feruloyl esterases (FAE-I and FAE-II) produced by the anaerobic fungus Neocallimastix strain MC-2 which cleave ferulic acid from O-(5-O-[(E)-feruloyl]-alpha-L- arabinofuranosyl)-(1-->3)-O-beta-D-xylopyranosyl-(1-->4)-D-xylopyranose (FAXX) were purified. The molecular masses of FAE-I FAE-II 69 24 kDa, respectively, under both denaturing nondenaturing conditions. Apparent Km maximum rate hydrolysis with FAXX 31.9 microM 2.9 mumol min-1 mg-1 for 9.6 11.4 FAE-II. was...

An extracellular p-coumaroyl esterase produced by the anaerobic fungus Neocallimastix strain MC-2 released groups from 0-[5-0-((E)-p-coumaroyl)-alpha-L-arabinofuranosyl]-(1----3)-0-beta -D-xylopyranosyl-(1----4)-D-xylopyranose (PAXX). The was purified 121-fold culture medium in successive steps involving ultrafiltration column chromatography on S-sepharose and hydroxylapatite, isoelectric focusing, gel filtration. native enzyme had an apparent mass of 11 kDa under nondenaturing conditions a...

Anaerobic fungi in ruminal fluid from cows eating Bermuda grass hay plus a grain and minerals supplement were evaluated for diversity sporangial morphotypes colony growth patterns the degradation of various lignocelluloses. In selective cultures containing streptomycin penicillin, an active population colonized leaf blades degraded fiber at rates extents almost equal to that total population. Three major consistently observed on blades: oval, globose, fusiform. Fungal colonies representing...

Different morphological types of rumen bacteria which degraded cell walls forage grasses with various in vitro digestibilities were evaluated electron microscopy. The majority these (i.e., about 70% or more) consisted two distinct types: (i) encapsulated cocci and (ii) irregularly shaped bacteria, resembling major fiber digesters found the rumen. Each type was capable degrading structurally intact walls. Differences (P less than equal to 0.02) percent ratio observed between Bermuda grass...

Three wild-type white rot fungi and two cellulase-less mutants developed from Phanerochaete chrysosporium K-3 (formerly Sporotrichum pulverulentum ) were tested for their ability to delignify grass cell walls improve biodegradation by rumen microorganisms. Fungal-treated control stems of Bermuda analyzed content ester- ether-linked aromatics using alkali extraction gas chromatography, in vitro dry weight digestion production volatile fatty acids fermentations with mixed ruminal...

trans-p-Coumaric acid inhibited the growth of Bacteroides ruminicola on both cellobiose and glucose, while trans-ferulic vanillin retarded growth. The phenolic monomers varied in their potential to inhibit succinogenes beta-glucosidase, carboxymethylcellulase, xylanase, with p-coumaric being most inhibitory. B. beta-glucosidase was less than 10% by all three compounds.

Ruminal bacteria or fungi were selected by the addition of cycloheximide streptomycin and penicillin, respectively, to ruminal fluid, weakening degradation lignified tissues in alfalfa Bermuda grass stems these treatments whole fluid evaluated vitro. Dry weight loss was similar for streptomycin-penicillin treatment, whereas that with treatment significantly higher ( P ≤ 0.05) than treatment. In grass, dry which equal. Both peak load (Newtons) stress less other both forages. Fungi colonized...

The degradation of forage cell walls by rumen bacteria was investigated with critical-point drying/scanning electron microscopy and ruthenium red staining/transmission microscopy. Differences were observed in the manner attachment different morphological types to plant during degradation. Cocci, constituting about 22% attached bacteria, appeared be degraded via capsule-like substances averaging 58 nm width (range, 21 84 nm). Many bacilli adhere substrates without distinct material, although...

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Leaves of sericea lespedeza exhibit a high proportion condensed tannin, resulting in poor forage quality. The white rot fungi Ceriporiopsis subvermispora and Cyathus sterocoreus are known to preferentially degrade lignin variety plants were evaluated for their ability tannin from leaves with the aim improving digestibility. Relative levels cutin, pectin, cellulose monitored as function fungal treatment by solid-state cross-polarization magic angle spinning 13C nuclear magnetic resonance...

Commercial enzyme mixtures are tested for their possibly selective degradation of flax ( Linum usitatissimum L.) stem components in relation to the retting process producing linen. Structural and chemical compositional results from treatments obtained using scanning electron microscopy, histochemistry, gas-liquid chromatography, 13 C cp mas nmr spectrometry, mid-infrared spectroscopy. Flaxzyme Ultrazym an enriched pectinase mixture (epm), which was not developed but is included comparison,...

Information on the interaction between mixed populations in rumen and plant phenolics is required to fully elucidate limitations of phenolic compounds forage digestibility. The objective this study was examine degradation Italian ryegrass (Lolium multiflorum L.) hay incubated with ruminal consecutive batch culture (CBC) or without acids extracted from cell walls. Each CBC consisted a series 10 cultures (3 replicates per culture) inoculated (10%, vol/vol) sequence at 48-h intervals microbial...