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PubMed1989

Analysis of water-soluble vitamins in total parenteral nutrition solution by high pressure liquid chromatography.

A stability-indicating high pressure liquid chromatographic method was developed to determine the stability of water-soluble vitamins in total parenteral nutrition mixtures. Folic acid and thiamine were determined by direct injection and precolumn enrichment, followed by UV detection. Nicotinamide and pyridoxine were determined simultaneously without sample pretreatment by UV detection of nicotinamide and fluorescence detection of pyridoxine. Riboflavin 5'-phosphate was also determined without elaborate sample handling and by fluorescence detection. Ascorbic acid was determined as the sum of ascorbic acid and dehydroascorbic acid. After derivatization to a quinoxaline the latter substance was determined by direct injection and fluorescence detection.

Ascorbic Acid↗
PubMed1992

Effects of cortical ablation on apomorphine- and scopolamine-induced changes in dopamine turnover and ascorbic acid catabolism in the rat striatum.

Levels of dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), ascorbic acid and dehydroascorbic acid (DHAA) were measured by HPLC in the striatum of rats whose fronto-parietal cortex had been unilaterally ablated after a single injection of apomorphine (1 mg/kg s.c.), scopolamine (0.6 mg/kg s.c.) or L-glutamate (500 mg/kg i.p.). Unilateral cortical ablation decreased striatal levels of glutamate in both striata ipsilateral (35%) and contralateral (17-25%) to the lesion. Apomorphine and scopolamine significantly increased (+94 and +122%, respectively) the DHAA/ascorbic acid ratio in the striata ipsilateral to the lesion in unoperated and sham-operated rats (+72 and +34%, respectively), but both drugs failed to increase it in ablated rats. L-Glutamate significantly increased the DHAA/ascorbic acid ratio in unoperated (+53%) and ablated rats (+37%). The increase in sham-operated rats (+34%) did not reach statistical significance. Apomorphine and scopolamine significantly decreased the DOPAC/DA ratio in the striata ipsilateral to the lesion of unoperated, sham-operated and ablated rats. The decrease in the DOPAC/DA ratio induced by apomorphine and scopolamine was greater in ablated rats than in sham-operated rats. L-Glutamate induced only minor changes in striatal DA and DOPAC levels. We conclude that the apomorphine- and scopolamine-induced increase in ascorbic acid oxidation in the striatum requires intact cortico-striatal glutamatergic pathways. Cortical ablation potentiates the apomorphine- and scopolamine-induced inhibition of striatal DA turnover.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1991

Vitamin C and vitamin E status in the spontaneously diabetic BB rat before the onset of diabetes.

Ascorbic acid (AA), dehydroascorbic acid (DHAA), and vitamin E were measured in tissues and plasma of 30 control and 30 spontaneously diabetic BioBreeding rats (BBdp) during development and before the onset of diabetes. At weaning, rats were fed an AIN-76 semisynthetic diet for 30, 64, or 113 days, after which plasma and tissues from 10 rats of each group were collected and analysed for AA, DHAA, and vitamin E. AA and DHAA levels were significantly increased in plasma and spleen of the diabetes-prone rats compared with those of the control group at 30 and 64 days, but the difference disappeared by 113 days. No differences were observed in liver, adrenals, thymus, and pancreas at any of the time periods. However, lower levels of vitamin E were observed in adrenal gland, thymus, and pancreas of the diabetes-prone rats. It is concluded that BBdp rats have an altered metabolism of AA, DHAA, and vitamin E, before the onset of diabetes. These changes could be due to genetic and physiological factors operating during development of this rat strain.

Adrenal Glands↗
PubMed1996

Glycation mediated crosslinking between alpha-crystallin and MP26 in intact lens membranes.

With advancing age, progressive crosslinking occurs between lens crystallin proteins and other lenticular components. This crosslinking may be involved in the development of senile cataracts. Experiments were conducted to determine whether non-enzymatic glycation could be involved in the crosslinking between lens alpha-crystallin and MP26, an abundant lens fiber cell membrane intrinsic protein. In vitro crosslinking of alpha-crystallin and MP26 of bovine lens membranes was observed in presence of two degradation products of ascorbic acid (ASA), dehydroascorbic acid (DHA) and threose. Alkali-washed bovine lens membranes, isolated after glycation with DHA and threose, contained both alpha-crystallin and MP26, as determined by immunoblot and double immunocytochemical labeling studies. In contrast, membranes incubated without these glycating compounds contained only MP26. SDS-PAGE analysis of [125I] alpha-crystallin incubated with lens membranes in the presence of threose showed a higher amount of radioactivity in high molecular weight aggregates than in the aggregates produced when alpha-crystallin and threose were incubated without membranes. A slot-blot immunoassay of alkali-washed human lens membranes showed a higher amount of covalently bound alpha-crystallin in aged, cataractous or diabetic lens membranes than was present in lens membranes from young normal donors. Based on the in vitro results, we hypothesize that non-enzymatic glycation is one of the vivo mechanisms in the crosslinking of alpha-crystallin to lens membrane proteins, such as MP26. This crosslinking may contribute significantly to the development of age-related and diabetic cataracts.

Aging↗
PubMed1995

Neuronal antioxidant system and MPTP-induced oxidative stress in the striatum and brain stem of the rat.

Levels of ascorbic acid (AA), dehydroascorbic acid (DHAA), glutathione (GSH), uric acid, dopamine (DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 3-methoxytyramine (3-MT), noradrenaline (NA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and 1-methyl-4-phenylpyridinium ion (MPP+) were determined in the striatum, striatal synaptosomes, and/or brain stem of 3- and 6-month-old male Wistar rats given MPTP 35-52 mg/kg IP. In older rats, MPTP 35 mg/kg caused a 38% death rate within 15 min-12 h. Levels of MPTP and MPP+ in the striatum, synaptosomes, and brain stem were directly correlated with the absolute MPTP dose/rat. MPTP decreased striatal DA metabolites and NA levels in the striatum and brain stem, and increased uric acid levels in all regions in all rats. All these changes were significantly correlated with MPP+ levels. GSH levels were increased in younger rats and decreased in older rats. AA oxidation was increased mainly in older rats. We conclude that acute lethality and regional brain MPTP and MPP+ levels depend upon the absolute dose of MPTP/rat rather than the relative dose/kg. In younger rats, the neuronal antioxidant GSH system is more efficient than in older rats, in which the response to MPP(+)-induced oxidative stress also involves AA oxidation. The increase in uric acid levels provides further evidence for a mechanism of MPTP neurotoxicity involving oxidative stress mediated by xanthine oxidase.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1996

Further investigation of allopurinol effects on MPTP-induced oxidative stress in the striatum and brain stem of the rat.

Levels of uric acid, xanthine, hypoxanthine, ascorbic acid (AA), dehydroascorbic acid (DHAA), glutathione (GSH), noradrenaline (NA), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 5-hydroxytryptamine (5-HT), 5-hydroxyindoleacetic acid (5-HIAA) 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 1-methyl-4-phenylpyridinium ion (MPP+) were determined in the striatum and/or in the brain stem of 3-month-old male Wistar rats given allopurinol (300 mg/kg day by gavage) for 3 days before a single MPTP 35 mg/kg dose IP. Allopurinol alone decreased uric acid and increased xanthine levels both in the striatum and in the brain stem; moreover, allopurinol decreased striatal DOPAC + HVA/DA ratio and increased 5-HIAA/5HT ratio in the brainstem. Allopurinol affected neither regional MPTP nor MPP+ disposition. Allopurinol potentiated the MPTP-induced decrease in the DOPAC+HVA/DA ratio and increase in striatal AA oxidation; in addition, allopurinol antagonised the MPTP-induced: (i) increase in uric acid levels; (ii) decrease in NA levels in both regions, in DA levels, and in the 5-HIAA/5-HT ratio in the brain stem: (iii) increase in AA oxidation in the brain stem. In conclusion, the MPP(+)-induced oxidative stress mediated by xanthine oxidase seems to be involved in DA depletion in the brainstem and in NA depletion in both regions; moreover, striatal uric acid may have an active role in the neuronal antioxidant pool.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1993

Correlation between 1-methyl-4-phenylpyridinium ion (MPP+) levels, ascorbic acid oxidation and glutathione levels in the striatal synaptosomes of the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated rat.

In 6-month-old male Wistar rats, levels of dopamine (DA), dihydroxyphenylacetic acid (DOPAC), ascorbic acid (AA), dehydroascorbic acid (DHAA), uric acid, glutathione (GSH) and 1-methyl-4-phenylpyridinium ion (MPP+) were determined by HPLC in the crude striatal synaptosomal fraction after single injections of MPTP 35 mg/kg i.p. 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) induced a 32.5% death rate within 15 min to 10 h. Groups of surviving rats were sacrificed 1, 3, 8 and 24 h after MPTP. MPTP significantly increased levels of DHAA and uric acid and decreased levels of DOPAC and GSH. Individual synaptosomal levels of MPP+ were correlated inversely with DOPAC (r = -0.601, P < 0.002) and GSH levels (r = -0.496, P < 0.02) and directly with levels of uric acid (r = +0.627, P < 0.001); these latter, in turn, were correlated with DHAA (r = +0.418, P < 0.05) and GSH levels (r = -0.357, P = 0.07). In conclusion, the response of the endogenous antioxidant system (increase in AA oxidation, decrease in GSH levels) correlates well with the MPTP-induced increase in uric acid levels and provides further evidence for a mechanism of MPTP neurotoxicity involving oxidative stress produced by xanthine oxidase.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1993

Effects of ageing on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) neurotoxic effects on striatum and brainstem in the rat.

In 3- and 18-month-old male Wistar rats, levels of dopamine (DA), dihydroxyphenylacetic acid (DOPAC), ascorbic acid (AA), dehydroascorbic acid (DHAA), noradrenaline (NA), uric acid, glutathione (GSH) and 1-methyl-4-phenylpyridinium ion (MPP+) were determined by HPLC in the striatum and/or in the brainstem 24 h after single injections of MPTP (12-35 mg/kg i.p.). Aged rats had lower baseline levels of AA and GSH, compared to young rats. In aged rats, MPTP 35 mg/kg induced a 70% death rate and a decrease in striatal DOPAC/DA ratio which was significantly correlated to MPP+ concentrations (r = -0.840, P < 0.005); in addition, MPTP did not increase AA oxidation. In the brainstem, the MPTP-induced decrease in NA levels and increase in uric acid levels were significantly correlated to the MPP+ concentrations (r = -0.709, P < 0.05, and r = +0.888, P < 0.001, respectively). In conclusion, evidence is given of a mechanism of toxicity of MPTP involving oxidative stress produced by xanthine oxidase; in addition, in aged rats the neuronal antioxidant system (levels of AA and GSH) is considerably lower than in young rats and may play an enabling role in the MPTP age-related neurotoxic effects on striatum and brainstem.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1995

Effects of allopurinol on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurochemical changes in the striatum and in the brainstem of the rat.

Levels of uric acid, xanthine, hypoxanthine, ascorbic acid (AA), dehydroascorbic acid (DHAA), glutathione (GSH), noradrenaline (NA), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) and 1-methyl-4-phenylpyridinium ion (MPP+) were determined in the striatum and/or in the brainstem of 3-month-old male Wistar rats, given allopurinol (500 mg/kg day by gavage) for 3 days before a single MPTP 52 mg/kg dose i.p. Allopurinol alone decreased uric acid and hypoxanthine levels in the striatum and in the brainstem; moreover, allopurinol increased AA oxidation and decreased striatal DA metabolites. Allopurinol affected neither regional MPTP and MPP+ levels nor the MPTP-induced inhibition of striatal DA oxidative metabolism. On the contrary, the MPTP-induced increase in uric acid levels and decrease in xanthine, hypoxanthine and NA levels were fully antagonised. Such findings demonstrate that the claimed MPP(+)-induced oxidative stress mediated by xanthine oxidase may be involved at least in the NA depletion; moreover, uric acid may have a physiological role as an active component of the neuronal antioxidant pool.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1995

Allopurinol protects against manganese-induced oxidative stress in the striatum and in the brainstem of the rat.

Levels of uric acid, xanthine, hypoxanthine, ascorbic acid (AA), dehydroascorbic acid, glutathione (GSH), noradrenaline (NA), dopamine (DA), dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and and 3-methoxytyramine were determined in the striatum and/or in the brainstem of 3-month-old male Wistar rats given manganese (MnCl2, 200 mg/kg/day for 7 days by gavage) alone or associated with allopurinol. Allopurinol alone (300 mg/kg/day for 4 days by gavage) decreased uric acid and increased xanthine levels both in the striatum and in the brainstem; moreover, allopurinol decreased the striatal DOPAC + HVA/DA ratio. Allopurinol antagonised the Mn-induced: (a) increase in the DOPAC + HVA/DA ratio; (b) increase in uric acid levels and AA oxidation; and (c) decrease in GSH and NA levels. We conclude that allopurinol may protect against Mn-induced oxidative stress by inhibiting both DA oxidative metabolism and xanthine oxidase-mediated formation of reactive oxygen species.

Allopurinol↗
PubMed1990

2-Imidazolethiones protect ascorbic acid from oxidation induced by copper.

The oxidation of ascorbic acid to dehydroascorbic acid was accelerated by metal ions such as copper. This stimulation of ascorbate oxidation was inhibited by the addition of 2-imidazolethiones and other sulfhydryl-containing compounds, but not by 2-imidazolones or phenytoin. Although the 2-imidazolethiones interacted with copper, as shown by a decrease in the ultraviolet absorbance of the compounds, the product formed still protected ascorbate from oxidation. The 2-imidazolethiones are proposed to complex copper through their free -SH groups.

Ascorbic Acid↗
PubMed1986

Analysis of digoxin at therapeutic concentrations using high-performance liquid chromatography with post-column derivatization.

A high-performance liquid chromatographic (HPLC) procedure has been developed for the analysis of digoxin in plasma at therapeutic concentrations. The assay method provides resolution of digoxin from its metabolites using a 15 cm X 4.6 mm HPLC column containing 3-micron octadecylsilane-bonded stationary phase. The effluent of the column is passed through a post-column reactor in which a fluorescent derivative is formed by the co-addition of hydrochloric acid and dehydroascorbic acid. Detection of the derivative is accomplished in a fluorometer with excitation at 336 nm and emission at 425 nm. The extraction efficiency for recovery of digoxin from plasma samples was 70% using chloroform-isopropanol (9:1) following a pre-wash with isooctane to remove endogenous substances. The calibration curve was linear (r = 0.9999) over the range 0.5-4 ng/ml digoxin in plasma using digitoxigenin as internal standard. The minimum detectable quantity of digoxin in plasma was 0.5 ng/ml at a signal-to-noise ratio of 4:1. Split-samples of digoxin control sera were assayed by the HPLC procedure and by the prescribed radioimmunoassay procedure. Excellent correlation was observed between the two methods (r = 0.999). No interference was noted when a selection of commonly co-prescribed drugs were evaluated for chromatographic co-elution or interference in detection with that of digoxin or the internal standard.

Chromatography, High Pressure Liquid↗
PubMed2005

Kinetic and thermodynamic characterization of the cobalt and manganese oxyhydroxide cores formed in horse spleen ferritin.

Horse spleen ferritin (HoSF) containing 800-1500 cobalt or 250-1200 manganese atoms as Co(O)OH and Mn(O)OH mineral cores within the HoSF interior (Co-HoSF and Mn-HoSF) was synthesized, and the chemical reactivity, kinetics of reduction, and the reduction potentials were measured. Microcoulometric and chemical reduction of HoSF containing the M(O)OH mineral core (M = Co or Mn) was rapid and quantitative with a reduction stoichiometry of 1.05 +/- 0.10 e/M forming a stable M(OH)(2) mineral core. At pH 9.0, ascorbic acid (AH(2)), a two-electron reductant, effectively reduced the mineral cores; however, the reaction was incomplete and rapidly reached equilibrium. The addition of excess AH(2) shifted the reaction to completion with a M(3+)/AH(2) stoichiometry of 1.9-2.1, consistent with a single electron per metal atom reduction. The rate of reaction between M(O)OH and excess AH(2) was measured by monitoring the decrease in mineral core absorbance with time. The reaction was first order in each reactant with second-order rate constants of 0.53 and 4.74 M(-1) min(-1), respectively, for Co- and Mn-HoSF at pH 9.0. From the variation of absorbance with increasing AH(2) concentration, equilibrium constants at pH 9.0 of 5.0 +/- 1.9 for Co-HoSF and 2.9 +/- 0.9 for Mn-HoSF were calculated for 2M(O)OH + AH(2) = 2M(OH)(2) + D, where AH(2) and D are ascorbic acid and dehydroascorbic acid, respectively. Consistent with these equilibrium constants, the standard potential for the reduction of Co(III)-HoSF is 42 mV more positive than that of the ascorbic acid reaction, while the standard potential of Mn(III)-HoSF is 27 mV positive relative to AH(2). Fe(2+) in solution with Co- and Mn-HoSF under anaerobic conditions was oxidized to form Fe(O)OH within the HoSF interior, resulting in partial displacement of the Co or Mn by iron.

Animals↗
PubMed2004

Characterization and quantitation of antioxidant constituents of sweet pepper (Capsicum annuum L.).

Sweet peppers (Capsicum annuum L.) cv. Vergasa have been studied at four maturity stages (immature green, green, immature red, and red). The individual phenolics (hydroxycinnamic acids and flavonoids), vitamin C (ascorbic acid and dehydroascorbic acid), and individual carotenoids were characterized and quantified. Five hydroxycinnamic derivatives and 23 flavonoids were characterized and quantified from the pericarp of sweet pepper by high-performance liquid chromatography-diode array detection-electrospray ionization-mass spectrometry. Identification was carried out by their UV spectra, chromatographic comparisons with authentic markers, identification of hydrolysis products, and tandem mass spectrometry analysis. Hydroxycinnamic derivatives, O-glycosides of quercetin, luteolin, and chrysoeriol, and a large number of C-glycosyl flavones have been characterized. Some of these compounds were found for the first time in nature. Clear differences in the individual and total phenolic content were detected between the different maturity stages. Immature green pepper had a very high phenolic content while green, immature red, and red ripe peppers showed a 4-5-fold reduction. Ascorbic acid was the main form of vitamin C, and its content increased as the pepper reached maturity. The red ripe stage had a relevant impact on the carotenoids content. Thus, immature green peppers showed the highest content of polyphenols, while red ripe fruits had the highest content of vitamin C and provitamin A.

Antioxidants↗
PubMed2005

Stability of copigmented anthocyanins and ascorbic acid in a grape juice model system.

The stability of red grape anthocyanins (Vitis vinifera) was evaluated in a model juice system during normal (25 degrees C) and accelerated storage (35 degrees C) in the presence of ascorbic acid. Rosemary polyphenolic cofactors (0, 0.2, and 0.4% v/v) were evaluated as anthocyanin stabilizing agents. Cofactor addition resulted in concentration-dependent hyperchromic (up to 178%) and bathochromic (up to 23 nm) shifts, indicating a more intense red coloration of the models. Anthocyanin and ascorbic acid degradation followed first-order kinetics during storage. Results showed that copigmented treatments underwent a lower conversion of L-ascorbic acid into dehydroascorbic acid during storage when compared to the control, favorably impacting the vitamin retention of these models. Copigmentation did not affect anthocyanin degradation in the absence of ascorbic acid but in its presence aided to retain a higher anthocyanin content than the control. This study indicated that the addition of anthocyanin cofactors could be used to reduce the pigment and vitamin degradation while masking detrimental color changes in anthocyanin containing products.

Anthocyanins↗
PubMed2005

Ozonated water extends the shelf life of fresh-cut lettuce.

The use of ozonated water as a sanitizer to extend the shelf life of fresh-cut lettuce and the effect on the antioxidant constituents (polyphenols and vitamin C) were investigated. Fresh-cut iceberg lettuce (Lactuca sativa L.) was washed at 4 degrees C using three different ozonated water dips [10, 20, and 10 activated by ultraviolet C (UV-C) light mg L(-1) min total ozone dose], and the dips were compared with water and chlorine rinses. Treated lettuce was packaged in air or active modified atmosphere packaging (MAP) (4 kPa of O2 + 12 kPa of CO2 balanced with N2) and stored for 13 days at 4 degrees C. Despite its strong oxidizing activity, ozonated water did not stimulate the respiratory activity of fresh-cut lettuce. Moreover, ozonated water maintained the initial visual appearance of fresh-cut lettuce and controlled browning during storage in air. Initially, ozonated water and chlorine reduced the total mesophilic population by 1.6 and 2.1 log, respectively, when compared with water. Active MAP was effective in controlling total microbial growth, achieving 2.0 log reduction in relation to samples stored in air at the end of storage. On the other hand, active MAP caused a 2.0-3.5 reduction of coliforms on sanitized samples compared with water-washed samples. The most efficient treatments were ozone 20 and ozone 10 activated by UV-C, which were as effective as chlorine. Changes in individual phenolic compounds were independent of the washing treatments. In air, chlorogenic and isochlorogenic acid contents increased noticeably after 13 days while monocaffeoyltartaric and dicaffeoyltartaric acids remained unchanged. MAP effectively suppressed accumulation of caffeoylquinic derivatives, whereas caffeoyltartaric derivatives decreased during MAP storage to reach similar levels. The content of vitamin C (ascorbic acid and dehydroascorbic acid) decreased during storage, particularly under MAP. Ozonated water could be an alternative sanitizer to chlorine for fresh-cut lettuce due to good retention of sensorial quality and browning control with no detrimental reduction in the antioxidant constituents.

Ascorbic Acid↗
PubMed2006

Antioxidant composition in cherry and high-pigment tomato cultivars.

Fourteen cultivars of cherry tomatoes and four cultivars of high-pigment tomato hybrids were cultivated in southern Italy, and the red-ripe fruits were analyzed for their content in different classes of antioxidants and for their antioxidant activity. Among the different cultivars, significant differences were found between lycopene, beta-carotene, alpha-tocopherol, vitamin C (ascorbic acid and dehydroascorbic acid), and total phenolic and flavonoid contents. LS203 and Corbus appear to be the cultivars with the highest content of lipophilic and hydrophilic antioxidants among cherry tomatoes, respectively. All cultivars of high-pigment tomato hybrids showed an expected exceptionally high lycopene content. Among them, the highest content of lipophilic and hydrophilic antioxidants was found in cv. HLY 13. Hydrophilic and lipophilic antioxidant activities were both significantly influenced by genotype. Such results highlight an existing unexploited variability in tomato germplasm and stress the need to evaluate the biodiversity and to support conventional breeding programs to improve tomato nutritional value.

Antioxidants↗
PubMed2003

Effects of ascorbic acid and analogs on the activity of testicular hyaluronidase and hyaluronan lyase on hyaluronan.

We have evaluated the inhibition of testicular hyaluronidase and hyaluronan lyase by L-ascorbic acid and chemical analogs. We observed that L-ascorbic acid, D-isoascorbic acid and dehydroascorbic acid inhibited both types of enzymes, but showed stronger effects towards hyaluronan lyase. But these compounds were observed to degrade the substrate, hyaluronan, by themselves. Of the other ascorbic acid analogs tested, saccharic acid inhibited hyaluronan lyase, while not affecting the enzymatic activity of testicular hyaluronidase, nor affecting the physic-chemical stability of hyaluronan. This is the first compound, to our knowledge, to be shown to possess such selective inhibition. Therefore, we propose that saccharic acid could serve as a lead compound for the development of potent and selective inhibitors of bacterial hyaluronan lyase or of polysaccharide lyase enzymes in general as we observed this compound to be capable of inhibiting chondroitinase ABC in addition to hyaluronan lyase.

Animals↗