A B S T R A C TConcentrations of the major jlavonoids and phenolic acids in the peel und cortex of fiuit of eight commercial apple cultivars were determined by H P L C . The multivariate statistical technique of correspondence analysis was applied to the polyphenol profiles to describe distinctive groups of cultivars and of polyphenois, and their joint correspondences.Cultural and growing conditions had u limited eflect on the polyphenol profiles of the cortex and peel. Chlorogenic acid was the principal polyphenol in the cortex with the lowest levels being in Red Delicious and the highest in Jerseymac, which were compensated by changes in phlorizin. Cortland had low levels of' chlorogenic acid and Gravenstein had high levels, but these were oflset by the levels of catechins.The quercetin, rhamnoside, was the principal phenolic compound for the peel data with low levels in Red Delicious, Cortland, Spartan and Jerseymac and high levels in Golden Delicious, Gravenstein and Northern Spy. Levels of chlorogenic acid, offset by levels of phlorizin and catechins, distinguished between Red Delicious and Cortland. Rutin was important in distinguishing between Jerseymac and Spartan.

The flavonoid glycosides of Spartan apples were isolated by column chromatography on polyamide and Sephadex resins and by RP-HPLC. They were characterized by and 13C NMR as phlorizin and the following glycosides of quercetin: -L-arabinofuranoside, d-D-galactopyranoside, /3-D-glucopyranoside, -L-rhamnopyranoside, /3-D-xylopyranoside. The coupling constants in the XH NMR spectra were used to establish anomeric configurations of all glycosides.

Extraction of Spartan apple (Malus domestica) fruit acetone powder and fractionation of the extract on DEAE‐agarose allowed detection and quantification of 10 glycosidases active toward 4‐methylumbelliferyl glycosides. Hydrolysis was measured fluorimetrically. The predominant activity, a β‐d‐galactosidase (EC 3.2.1.23), labile upon purification, was stabilized by soluble PVP. Molecular weights, measured by gel permeation HPLC, pH optima and Km values were obtained for most glycosidase activities. Multiple forms of several activities were found. The major α‐d‐ and β‐d‐galactosidases were resolved on phosphocellulose. The β‐d‐galactosidase so obtained had associated α‐l‐arabinopyranosidase and β‐d‐fucosidase activities which were retained upon GP‐HPLC. Mixed substrate kinetic analysis and inhibition analysis of this fraction indicated that the enzyme has 3 catalytic sites, 1 for each substrate, whose substrates mutually influence each other's activity positively.

The intracellular a-aminoadipic acid pool in Streptomyces clavuligerus mycelium growing in a starchpeptone medium decreased during the late exponential and stationary phases when cephamycin was being produced; however, the amino acid accumulated extracellularly. Although the specific activity of lysine e-aminotransferase (LAT) decreased during this period, there was no indication that the extracellular a-aminoadipic acid functioned as a precursor reserve for synthesis of the fl-lactam antibiotic. MeaSurement of LAT activity in cultures grown in defined media with starch and various nitrogen sources indicated that the enzyme was synthesized preferentially only during early growth. In its insensitivity to induction by a precursor, and in its susceptibility to carbon catabolite repression, LAT behaved as a secondary metabolic pathway enzyme. Unexpectedly, however, the enzyme increased in specific activity when cultures were supplemented with excess phosphate. Unlike LAT, cadaverine aminotransferase was inducible by Iysine or cadaverine and insensitive to phosphate; its features were consistent with a role in the catabolism of lysine by S. clavulioerus.

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