TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The feedstock is pretreated with at least one irradiation, sonication, oxidation, pyrolysis and steam explosion to produce reduced recalcitrance lignocellulosic or cellulosic material. The irradiation is performed with an electron beam. The method involves converting the polycarboxylic acid to the chemically converted product. The chemical converting process is performed by polymerization, condensations, isomerization, esterification, alkylation, oxidation, amination, acid halide formation, reduction, hydrogenation, cyclization, ion exchange, anhydration, acylation and their combinations, or catalytic conversion, noncatalytic conversion and their combinations. The treating is performed initially with one of more enzymes to release one or more sugar from the lignocellulosic or cellulosic material followed by one or more organisms to produce the polycarboxylic acid. Preferred Components: The sugar is chosen from glucose, xylose, sucrose, maltose, lactose, mannose, galactose, arabinose, fructose, and disaccharides of cellobiose, sucrose or polysaccharides, or their mixtures. The treating step converts one or more sugars to an intermediate product before to conversion to the polycarboxylic acid. The intermediate product is ethanol or glycol. The sugar is converted to intermediate product by fermentation. The polycarboxylic acid is chosen from oxalic acid, malonic acid, succinic acid, tartaric acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, maleic acid, fumaric acid, glutaconic acid, traumatic acid, muconic acid, phthalic acid, isophthalic acid, terephthalic acid, citric acid, isocitric acid, aconitic acid, mellitic acid and their mixtures. In step (a) of the above-mentioned method the polycarboxylic acid is succinic acid. The product is chosen from tetrahydrofuran, gamma -butyrolactone, 2-pyrrolidone, N-methyl-2-pyrrolidone (NMP), N-vinyl-2-pyrrolidone, succinimide, N-hydroxysuccinimide, succinimide, succinyl chloride, succinic anhydride, maleic anhydride, 1,4-diaminobutane, succinonitrile, 1,4-butanediol and dimethyl succinate. The inorganic salts include monosodium phosphate, disodium hydrogen phosphate, sodium chloride, magnesium chloride, and calcium chloride. The nitrogen source includes yeast extract. The cellulosic or lignocellulosic material receives 10-50 Mrad radiation. The feedstock is pretreated with ionizing radiation to produce reduced recalcitrance lignocellulosic or cellulosic material. The ionizing radiation is performed with an electron beam. The polycarboxylic acid in the step (d) of the above-mentioned method is not succinic acid. EXAMPLE - No suitable example given.