A method of identifying a natural product comprising NP—[X].sub.n is provided. The method includes several steps. The first step includes selecting an organism having a biosynthetic pathway for producing the natural product comprising NP—[X].sub.n using a bioinformatics algorithm. The second step includes preparing a sample suspected to contain NP—[X].sub.n including a complex cellular metabolite mixture from an organism. The third step includes reacting the sample suspected to contain NP—[X].sub.n with reactivity probe Y according to Scheme I: Scheme I. NP—[X].sub.n represents a natural product NP having a chemical moiety X that is susceptible to chemical modification by reactivity probe Y to form at least one product adduct NP—[X].sub.n-m [Z].sub.n in which chemical moiety X reacts with reactivity probe Y to form adduct Z, wherein n ranges from 1 to about 10 and m is at least 1 and m≦n. The fourth step includes optionally dereplicating the product collection of at least one known labeled metabolite to provide a depleted product collection including at least one unknown labeled metabolite. The fifth step includes determining the structure of the at least one unknown labeled metabolite, thereby identifying the natural product comprising NP—[X].sub.n.

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A method of identifying or evaluating synergistic combinations of actives such as skin-care actives that improve the metabolism of a cell and provides an advantage over using the actives alone. The method includes contacting cells with test agents, alone and in combination, and determining a response of the cells to the test agent(s), wherein the response corresponds to a change in a metabolic indicator associated with glycolysis and a change in a metabolic indicator associated with oxidative phosphylation.

The present invention provides, among other things, improved substrate clearance assays for lysosomal enzyme that are particularly useful for measuring potency of lysosomal enzymes or other therapeutics for treatment of lysosomal storage diseases. In particular, the present invention combines a physiologically relevant substrate cell assay and an efficient scintillation based detection method.

The present disclosure relates to methods and apparatus for identifying metabolic pathways and metabolites in complex biological samples. In particular, the present disclosure relates to a method and apparatus to increase the confidence of metabolite identification in metabolomics, such as in untargeted metabolomics data, using various statistical tools, such as over representation and enrichment analysis.

The presently disclosed subject matter relates to methods of screening raw materials and pet food products to manufacture a palatable pet food product. The presently disclosed subject matter also relates to methods for identifying compounds that modulate the activity and/or expression of an olfactory receptor.

The methods described herein enable the evaluation of compounds on subjects to assess their therapeutic efficacy or toxic effects. The target of analysis is the underlying biochemical process or processes (i.e., metabolic process) thought to be involved in disease pathogenesis. Molecular flux rates within the one or more biochemical processes serve as biomarkers and are quantitated and compared with the molecular flux rates (i.e., biomarker) from control subjects (i.e., subjects not exposed to the compounds). Any change in the biomarker in the subject relative to the biomarker in the control subject provides the necessary information to evaluate therapeutic efficacy of an administered drug or a toxic effect and to develop the compound further if desired.

Compositions and methods for the measuring toxicity, antioxidant capacity, and oxidative stress are provided.

The present invention relates to a method for identifying substances which prime cells for a stress response by determining the respiration activity of the cells treated with a candidate substance in comparison to cells not treated with the candidate substance.

Methods of preparing a crosslinked hydraulic fracturing fluid include combining a hydraulic fracturing fluid comprising a polyacrylamide polymer with a plurality of coated proppants. The plurality of coated proppants include a proppant particle and a resin proppant coating on the proppant particle. The resin proppant coating includes resin and a zirconium oxide crosslinker. The resin includes at least one of phenol, furan, epoxy, urethane, phenol-formaldehyde, polyester, vinyl ester, and urea aldehyde. Methods further include allowing the zirconium oxide crosslinker within the resin proppant coating to crosslink the polyacrylamide polymer within the hydraulic fracturing fluid at a pH of at least 10, thereby forming the crosslinked hydraulic fracturing fluid.

The invention provides a breath test for assessing a metabolic phenotypeand/or assessing a disease state.