The Italian Journal of Biochemistry

V O L. 5 6, N. 1 MARCH 2007

Purification of Euphorbia characias Latex Peroxidase By Calmodulin–Affinity Chromatography
Francesca Pintus, Anna Mura
Department of Applied Sciences in Biosystems, University of Cagliari, Monserrato, Cagliari, Italy

The Italian Journal of Biochemistry: 2007; 56(1): 1-5

Abstract. A new procedure to purify to homogeneity an Euphorbia characias latex peroxidase is performed employing a calmodulin–Sepharose column as affinity chromatography. The advantage of this approach is the isolation of a peroxidase under fast and mild elution conditions with a high recovery in total activity.

Rat liver xanthine oxidoreductase: Effect of adenine on the oxidase and dehydrogenase activities
Kevork Hagopian
University of California, School of Veterinary Medicine, Department of Molecular Biosciences, Davis, USA

The Italian Journal of Biochemistry: 2007; 56(1): 6-17

Abstract. Xanthine oxidase (XO) and total oxidase plus dehydrogenase (XO+XDH) activities from rat liver were measured in the presence or absence of adenine in extracts prepared with or without DTT/PMSF in homogenization buffer. Presence of adenine in extracts, prepared with or without DTT/PMSF, caused a 45-60% decrease in XO and XO+XDH activities. Removal of adenine by dialysis from extracts prepared with or without DTT/PMSF resulted in the recovery of XO and XO+XDH activities to almost their pre-dialysis control levels. Enzyme activity after 24hr storage at -20°C depended on the presence or absence of DTT/PMSF and adenine, with both XO and XO+XDH activities being lower in extracts with the combined presence of DTT/PMSF and adenine. Incubation of extracts at 37°C for 30 minutes resulted in increased XO and XO+XDH activities, however, adenine-treated samples did not differ from their pre-incubation activities. The molecular mass of the enzyme from control and adenine-treated extracts was unchanged (300 kDa). Adenine-treated extracts prepared with or without DTT/PMSF showed higher D/O ratios in all post-dialysis samples when compared with their pre-dialysis ratios. The results suggest that adenine may play a role in preventing the dehydrogenase to oxidase conversion during extract preparation, storage, overnight dialysis and heat treatment.

Plasma levels of adrenomedullin and atrial natriuretic peptide in patients with congestive heart failure of various etiologies
M. Randa Abdel Kader, Grace B.D.M., Badawi N.E.S.
*Medical Biochemistry

The Italian Journal of Biochemistry: 2007; 56(1): 18-27

Abstract. Objective: The aim of this study was to evaluate the plasma levels of the adrenomedullin (ADM) and atrial natriuretic peptide (ANP) in adult and pediatric patients with congestive heart failure (CHF) of various etiologies and to investigate their relations with haemodynamic variables e.g. echocardiographic left ventricular ejection fraction (LVEF) and fractional shortening (FS). Subjects and Methods: The study was made in 38 adult and 21 pediatric patients with CHF of various etiologies and compared with 15 adult and 10 pediatric normal healthy controls. Patients with CHF were classified according to the New York Heart Association (NYHA) functional classification into grades II to IV in adult patients and into grade IV in all pediatric patients. ADM and ANP plasma levels were determined prior to the treatment with enzyme immunoassay. Results: A statistically significant difference in the plasma levels of ADM and ANP were found between pediatrics and adult patients and corresponding healthy controls. Their levels were progressively increased with severity of NYHA class in adult patients. We found a significant positive correlation between plasma levels of each of ADM and ANP and pulse rate, systolic and diastolic blood pressure; and a significant negative correlation between their plasma levels and echocardiographic LVEF and FS. A significant positive correlation between plasma levels of ADM and ANP in both pediatrics and adult patients were also found. Conclusion: Plasma levels of ADM and ANP increased in adult and pediatric patients with CHF irrespective of the cause. They were positively correlated with each other and negatively correlated with LVEF and FS. These findings might have important clinical implications in that a noninvasive blood test may be used to identify high-risk subjects for HF for more invasive procedures..

Fenugreek seeds modulate 1,2-dimethylhydrazine-induced hepatic oxidative stress during colon carcinogenesis
T. Devasena*, P. Venugopal Menon
*1Department of Biotechnology, Mother Teresa Women’s University, Kodaikanal, Tamil Nadu, India

The Italian Journal of Biochemistry: 2007; 56(1): 28-34

Abstract. 1,2-dimethylhydrazine (DMH) is a colon carcinogen which undergoes oxidative metabolism in the liver. We have investigated the modulatory effect of fenugreek seeds (a spice) on colon tumor incidence as well as hepatic lipid peroxidation (LPO) and antioxidant status during DMH-induced colon carcinogenesis in male Wistar rats. In DMH treated rats, 100% colon tumor incidence was accompanied by enhanced LPO and a decrease in reduced glutathione (GSH) content as well as a fall in glutathione peroxidase (GPx), glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT) activities. Inclusion of fenugreek seed powder in the diet of DMH treated rats reduced the colon tumor incidence to 16.6%, decreased the LPO and increased the activities of GPx, GST, SOD and CAT in the liver. We report that fenugreek modulates DMH-induced hepatic oxidative stressduring colon cancer

Comparison of pistachio hull essential oils from different tunisian localities
Thouraya Chahed, Wissal Dhifi, Ibtissem Hamrouni, Kamel Msaada, Amor Bellila, Mohamed E. Kchouk, Brahim Marzouk
Unité des Plantes Aromatiques et Médicinales, Centre de Biotechnologie du Technopole de Borj Cedria, Hammam-Lif, Tunisia

The Italian Journal of Biochemistry: 2007; 56(1): 35-39

Abstract. Pistachio (Pistacia vera L.) fruit is well known for its oleaginous and edible seed. Less information is available about the hull constituted by the epicarp and the mesocarp. This part of the fruit contains an essential oil that can be valorized. Tunisia is one of the countries cultivating pistachio trees. This work presents essential oil composition of pistachio hulls (Mateur variety) from different geographical localities: Grombalia (North-East), Kairouan (Middle) and Sfax (Middle-East). Yields were more important in Sfax samples (0.53% on a dry weight basis). Alpha-terpinolene was the major compound for Grombalia fruits (35.7%), whereas Kairouan and Sfax samples where characterized by a-pinene (42.5 and 43.8% respectively). For all samples, monoterpene hydrocarbons predominated (more than 79.8% of the essential oil).

Essential oil composition of Hypericum triquetrifolium Turra. aerial parts
Hosni Karim, Msaada Kamel, Ben Taarit Mouna, Chahed Thouraya, Marzouk Brahim
Aromatic and Medicinal Plants Unit, Biotechnologic Center in Borj-Cedria Technopol, Hammam-Lif, Tunisia

The Italian Journal of Biochemistry: 2007; 56(1): 40-46

Abstract. The essential oil obtained by hydrodistillation from the aerial parts of Tunisian endemic Hypericum triquetrifolium Turra (Clusiaceae) was analyzed using GC and GC-MS. One hundred and nine compounds consisting of 92.2% of total detected constituents were identified. Sesquiterpene hydrocarbons were the main constituents (59.37%), Alpha-humulene, cis-calamenene, d-cadinene, bicyclogermacrene, eremophilene, b-caryophyllene and (E)-g-bisabolene were found as the main ones. Alpha-pinene (10.33%) was detected as the main monoterpene hydrocarbons (12.19%). The oxygenated sesquiterpenes constituted (9.33%); caryophyllene oxide (1.38%) was reported as the main constituent of this fraction. The oxygenated monoterpenes were weakly represented (4.62%) and consisted of constituents in low percentages (<1%).

Variations in the Essential Oil Composition from Different Parts of Coriandrum sativum L. Cultivated in Tunisia
Kamel Msaada, Karim Hosni, Mouna Ben Taarit, Thouraya Chahed, And Brahim Marzouk
Aromatic and Medicinal Plants Unit, Biotechnologic Center in Borj-Cedria Technopol, Hammam-Lif, Tunisia

The Italian Journal of Biochemistry: 2007; 56(1): 47-52

Abstract. Essential oils obtained by hydrodistillation from different organs (flowers, leaves, stems and roots) of Tunisian coriander (Coriandrum sativum L.) was analyzed. GC and GC-MS analysis enabled us to identify 64 compounds and revealed great qualitative and quantitative differences between the analyzed parts. In all organs, the main compound was (E)-2-dodecenal, followed by (E)-2-tridecenal, g-cadinene, (Z)-myroxide, neryl acetate and eugenol. Multivariate analysis (PCA) revealed a high similarity in the essential oils composition between upper leaves and flowers in one hand and basal leaves, roots and stems on the other hand. Further, it has been reported an organ-dependant distribution of essential oil compounds.

Effects of L-Carnitine on RBC Membrane Composition and Function in Hyperinsulinemic Rats
P. Rajasekar, K. Balasaraswathi, C.V. Anuradha
Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalai Nagar, Tamil Nadu, India

The Italian Journal of Biochemistry: 2007; 56(1): 53-60

Abstract. The purpose of the study was to investigate the effects of L-carnitine (CA) on the susceptibility of erythrocyte (RBC) to peroxide-induced lipid oxidation, RBC membrane composition, ATPases activity and oxidative stress in fructose-fed hyperinsulinemic rats. The rats were subjected to experimental hyperinsulinemia and hyperglycemia by feeding a high fructose diet (60g/100g) for 6 weeks. The rats showed significant alterations in the RBC membrane composition. The protein content was lower than control animals, while cholesterol, phospholipids and free fatty acids were higher in fructose-fed animals. Significant differences in the total carbohydrate and relative proportions of hexose, hexosamine, sialic acid and fucose of membranes were observed. In these rats, membrane-bound ATPases (total ATPase, Na+, K+ ATPase, Mg2+ and Ca2+ ATPases) were significantly lower while thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides (LHP) in RBC membrane were significantly higher than those of control rats. The red cells were more susceptible to peroxide-induced oxidative stress that correlated with reduced levels of vitamin E found RBC membrane. When fructose-diet fed rats were treated simultaneously with CA (300mg/kg b.w/day, i.p), such alterations in membrane composition and enzyme activities did not occur. Effects of fructose loading on lipid peroxidation was also alleviated by CA. These findings suggest that high levels of dietary fructose is detrimental to RBC membrane integrity and that CA may have membrane stabilizing effects in this diet-induced model of type 2-diabetes.

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