facilities within the weapons complex. The inventory of chemicals and mixtures was used to identify generic chemical mixtures to be used by DOE'S Subsurface Science Program in basic research on the subsurface geochemical and microbiological behavior of mixed contaminants (DOE 1990a and b). The generic mixtures contain specific radionuclides, metals, organic ligands, organic solvents, fuel hydrocarbons, and polychlorinated biphenyls (PCBs) in various binary and ternary combinations. The mixtures are representative of in-ground contaminant associations at DOE facilities that are likely to exhibit complex geochemical behavior as a result of intercontaminant reactions and/or microbiologic activity stimulated by organic substances. Use of the generic mixtures will focus research on important mixed contaminants that are likely to be long-term problems at DOE sites and that will require cleanup or remediation.The report provides information on the frequency of associations among different chemicals and compound classes at DOE waste sites that require remediation. For example, radionuclides such as uranium, plutonium, strontium, and cobalt were found, in some cases, to be disposed of with organic substances (e.g., organic acids, complexing agents, and solvents) that could influence radionuclide geochemical behavior and subsurface transport. Knowledge of the types of chemicals that coexist in waste sites is important to remediation for various reasons:. The efficiency of many biotic and abiotic treatment processes for soil and ground-water contaminants is affected by the presence of co-contaminants.m Multiple contaminant species may be treated simultaneously and more effectively by specific aboveground or in-ground techniques if the nature of the contaminant association is understood in advance.rn Certain types of chemical mixtures may require special precautions or the development of new remediation strategies or techniques.rn In-ground remediation activities may selectively mobilize certain mixtures of chemical constituents to air or ground water, thereby increasing environmental risk; or some mixtures may be stabilized, thus reducing environmental impact.iiiThe report provides quantitative information on the frequency of occurrence of binary, ternary, and higher order contaminant mixtures in the 91 waste sites. This quantitative information may be used to refine or guide the development of new aboveground and in situ remediation strategies that can be used throughout the weapons complex.Scientists T waste sites at 18 U.S. Department of Energy (DOE) facilities. The review was conducted to identify (1) inorganic and organic contaminants found within soil and ground water at DOE waste sites, ( 2 ) their concentration ranges, and (3) their frequency of occurrence as single compounds and as binary, ternary, quaternary, and higher order contaminant mixtures. Fuel hydrocarbons, chlorinated hydrocarbons, radionuclides, metals, inorganic anions, and ketones were the contaminant classes most frequently measured in the ground at...

p-Couimaric acid (4-hydroxycinnamic acid) and ferulic acid (4-hydroxy-3-methoxycinnamic acid) have been identified as conistituen-ts of cutin. Their reduction products were isolated fromi a phenolic fraction released from the cutin of the fruits of apple, peach, pear, and two varieties of tomato and apple leaf by treatment with LiAlH4 or LiAlD4. They were identified by comlibined gas chromatography and mass spectrormetry. p-Cotimaric acid was present in all samples of cutill (0.07-O.5i3% by weight), whereas only peach and pear cutin con-tainied measuirable aniotunits of ferulic acid (0.007% and 0.035.%, respectively). Both p-coutnaric acid and ferulic acid were idenitified to be conistituients of the insoluble material recovered after partial hydrolysis (12-42% loss) of cutin in 1 M NaOH at 80 C. A significanit part (48%) of the p-coumlaric acid contain-ed inl tomato cutin was contained in the insoluible material recovered after partial degradation (7.4%) of this cutin with 0.01 m NaOH. These data indicate that these phenolic components are tightly (possibly covalently) bountid to ctutin. Similar analysis of the phenolic fractions froni the stuberins of potato, sweet potato, turnip, rutabaga, carrot, anid red beet revealed that they contained onily fertilic acid (0.0.5-0.22%). Ferulic acid was identified as a constituen-t of the insoluible m-laterial recovered after partial hv-drolvsis of potato and beet suberins (34% and 32% loss, respectively) in 1 m NaOH at 80 C. A major part (65%) of the fertulic acid conitain-ed in potato suberin was contained in the inisoluble inaterial recovered after partial (26.8% loss) degradation of this suberin with 0.01 M NaOH. Fertulic acid appears to be tightly (probably covalently) bound to suiberin.Cutin, the structural component of plant cuticle, is a polymer of hydroxy fatty acids (8). The common major components of this polymer are palmitic acid, 16-hydroxypalmitic acid, 10,16-dihydroxypalmitic acid, or its positional isomers, oleic acid, 18-hydroxyoleic acid, 18-hydroxy-9, 10-epoxystearic acid, and 9, 10, 18-trihydroxystearic acid. The composition of the aliphatic components of suberin from the underground parts of plants is somewhat similar to that of cutin; however, there are significant quantitative differences between the composition of these two types of protective polymers (5-8). One major difference appears to be that suberin preparations contain quite large proportions of phenolic materials, while cutin preparations contain very little phenolic compounds, although the phenolics which might be present in cutin preparations have not been examined. In this paper we report experimental evidence which strongly suggests that p-coumaric acid and 'or ferulic acid are covalently attached to cutin and suberin. MATERIALS AND METHODS Isolation of Phenolic Compounds from Cutin and Suberin afterLiAlH1 and LiAID4 Degradation. Powdered cutin from apple leaf and fruits of apple, tomato, peach, and pear were obtained as previously described (11). A 500 mg sample of each cutin...

Data were collected from six experiments using duodenally cannulated Holstein dairy cows (88 combinations of cow and period) to evaluate the relationship between urinary purine metabolites and microbial N flow. Experiments evaluated the effects of dietary factors on microbial N production, which included 1) varying concentrations of ruminally degradable protein and nonstructural carbohydrates, 2) supplemental sources of protected amino acids, 3) grass silage treated with fibrolytic enzymes, 4) bacterial inoculation of corn silage, and 5) ruminal starch availability as affected by corn silages of varying maturity. The coefficient of determination for individual experiments that measured the relationship between microbial N flow and allantoin or uric acid excretion in urine ranged from 0.01 to 0.68 and 0.02 to 0.82, respectively. Across all experiments, the coefficients of determination between microbial N flow and allantoin or uric acid excretion in urine were r2 = 0.002 and 0.11, respectively. Removal of data from one experiment improved the overall coefficient of determination between microbial N flow and urinary uric acid to r2 = 0.32. Urinary allantoin excretion across experiments was negatively correlated with microbial N flow, but urinary allantoin excretion within experiments was positively correlated with microbial N flow. Uric acid excretion in urine was positively correlated with microbial N flow across and within experiments, except for one experiment. Our data demonstrate that uric acid excretion in urine can be used to predict microbial N production, except in early lactation, and that urinary allantoin excretion cannot be used to predict microbial N production accurately among cows at different stages of lactation.

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