Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by P.C. Chikezie
Total Records ( 10 ) for P.C. Chikezie
  C.O. Ibegbulem and P.C. Chikezie
  Kunu-zaki beverage is a popular cereal-grain based non-alcoholic drink traditionally produced from sprouted cereal grains like sorghum, millet, maize or their mixtures. Unsprouted grains can also be used, thereby saving time spent during sprouting without compromising sensory property. The present study sought to investigate, in comparative terms, the biochemical indices and sensory scores of Kunu-zaki beverages produced from Sprouted Guinea Corn (SGC) and Unsprouted Guinea Corn (USGC) as well as establishing correlation between these parameters. Production of Kunu-zaki beverages from USGC and SGC was carried out using standard procedures. Samples of the beverages were analyzed for glucose, protein and hydrogen ion concentrations in concurrence with sensory evaluation scores. The results indicated that the Kunu-zaki beverages produced were of comparable (p>0.05) acidity values. Protein and glucose concentrations of Kunu-zaki beverage produced from SGC were significantly higher (p<0.05) than beverage produced from USGC. Specifically, Kunu-zaki beverage produced from SGC gave: [protein] = 10.6±2.62 g L-1 and [glucose] = 500.0±4.90 mg dL-1, whereas beverage produced from USGC gave [protein] = 3.0 g L-1 and [glucose] = 335.3±2.8 mg dL-1. Sensory attributes of the beverages were not significantly different (p>0.05). The pH, mouthfeel, protein and glucose contents of the beverages had strong positive effects on their tastes. The protein content of Kunu-Zaki beverage produced from SGC had marginal effect on its taste. Although the levels of some biochemical parameters were reduced when Kunu-zaki beverage was produced from USGC, it did not affect its sensory property.
  C.O. Ibegbulem , P.C. Chikezie , C.O. Nweke , C.E. Nwanyanwu and D.C. Belonwu
  Effects of processing pineapple-based must into wines by Anaerobic Fermentation (AnF) only instead of Aerobic and Anaerobic Fermentations (AAnFs) were investigated. Control musts were subjected to aerobic fermentation, AnF and clarification for 7, 83 and 30 days, respectively. Test musts clarified in the course of 90 days AnF. Wines produced by AAnFs were more acidic (pHtest = 3.17±0.01, pHcontrol = 3.28±0.01, p<0.05), had more total acids (test = 0.70±0.01 g tartaric acid/100 mL, control = 0.66±0.00 g tartaric acid/100 mL, p<0.05), fixed acids (test = 0.49±0.02 g malic acid/100 mL, control = 0.39±0.01 g malic acid/100 mL, p<0.05), alcohol (test = 12.72±0.01%, control = 11.36±0.00%, p<0.05). Furthermore, wines produced by AnF had more volatile acids (test = 0.39±0.00 g acetic acid/100 mL, control = 0.33±0.01 g acetic acid/100 mL, p<0.05) and glucose (test = 1.50±0.01 g/100 mL, control = 1.40±0.00 g/100 mL, p<0.05). Pineapple-based must processed into wines by anaerobic fermentation produced organoleptically preferred good quality white dry table pineapple wines with lower derivable energy content.
  P.C. Chikezie , A.R. Akuwudike and C.M. Chikezie
  Enzyme activity depends largely on environmental conditions such as temperature and pH. The stabilities of Polyphenol Oxidase (PPO) extracted from Solanum melongenas and Musa sapientum fruits pre-incubated in varying thermal and pH conditions were carried out. Enzyme activity was measured by spectrophotometric methods. The reaction mixture contained 3.5 mL of 0.20 M phosphate buffer (pH = 6.8), 1.0 mL of 0.75 mM catechol and 0.5 mL of enzyme solution. PPOS. melongenas and PPOM. sapientum gave different temperature and pH optima. The temperature-activity profile of PPOS. melongenas and PPOM. sapientum showed a strong positive correlation (r = 0.907363). At pH = 10.0, PPOM. sapientum activity represented 65.3% decay in enzyme activity, whereas PPOS. melongenas represented 79.3% decay in enzyme activity. PPOS. melongenas and PPOM. sapientum stability at pre-incubated temperatures of 20, 50 and 60°C and pH values of 3.5, 6.0 and 8.0 were measured. Residual activities of PPOS. melongenas and PPOM. sapientum showed a strong positive correlations under the same experimental thermal conditions, with exception at 20°C (r = 0.693375). Specifically, pre-incubation of PPOM. sapientum for t = 90 min at 60°C caused 18.4% decay in relative activity of PPOM. sapientum. At t = 90 min, pre-incubation of PPOM. sapientum, in pH = 3.5 caused decay in activity within the range of 30.8-36.1%, whereas PPOM. sapientum pre-incubated in pH = 6.0 and pH = 8.0 gave decay in activity within the range of (1.5-9.8%) and (2.7-6.5%), respectively. PPOS. melongenas and PPOM. sapientum showed relatively higher stabilities as the incubation pH tended towards alkaline conditions, whereas the two experimental temperatures (20 and 60°C) promoted destabilization.
  P.C. Chikezie , A.R. Akuwudike , C.M. Chikezie and C.O. Ibegbulem
  Largely, kinetic properties of Polyphenol Oxidase (PPO) involved the study of enzyme extracts obtained from whole fruits and vegetables. In the present study, PPO was extracted from three segments of Solanum melongenas and Musa sapientum fruits and partially purified. The specific activity of PPO was measured at each purification step to ascertain level of enzyme purity. In all cases, PPO conformed to Michaelis-Menten kinetics, showing different values of kinetics parameters. Michaelis-Menten constant for PPO (PPOKm) of S. melongenas mid-section and anterior segments showed no significant difference (p<0.05), whereas the posterior gave PPOKm = 4.6±0.49 mM (p>0.05). Maximum PPO activity (PPOVmax) was highest in the posterior segment: PPOVmax = 0.602±0.09 U. Mid-section of M. sapientum exhibited the highest Km value (PPOKm = 5.8±0.69 mM) compared with the anterior (PPOKm = 3.9±0.69 mM) (p>0.05) and posterior PPOKm = 4.9±0.11 mM segments (p<0.05). Overall, M. sapientum PPOKm values were relatively higher than those of S. melongenas. Posterior S. melongenas exhibited the highest PPOVmax = 0.602±0.09 U, whereas the lowest value was registered in the anterior segment of M. sapientum PPOVmax = 0.234±0.09 U. Substrate specificity for PPO (PPOVmax/Km) extracted from various segments of S. melongenas was in the increasing order of Mid-section > Posterior > Anterior, whereas that of M. sapientum was Mid-section > Anterior > Posterior. PPOVmax/Km between the two fruits showed strong positive correlation (r = 0.862339). Catechol was a better substrate for PPOS. melongenas than PPOM. sapientum. The experimentally observed kinetic parameters of S. melongenas and M. sapientum signified the presence of PPO isoenzymes and non-uniform distribution of PPO in the two fruits.
  V.O. Njoku , P.C. Chikezie , M.A. Kaoje , C.C. Monago and A.A. Uwakwe
  Studies were carried out to ascertain some kinetic properties of alkaline phosphatase (ALP) extracted from Lepus townsendii liver. Incubation of ALP extract with 4-nitrophenylphosphate (4-NPP) in glycine-NaOH buffer mixture at 37°C for 30 min formed the basis for determination of enzyme activity. Spectrophotometric method was used to assay for the enzyme activity for 30 min and the kinetic constants-maximum enzyme velocity (Vmax) and Michealis-Menten constant (Km) were evaluated. The Km and Vmax values were 0.5x10-3 M and 20x10-6 M min-1, respectively. Inhibition studies showed that ALP activity was competitively inhibited by 0.67 mM sodium hydrogen orthophosphate (NaH2PO4) and the inhibition constant (Ki) was 0.9x10-3 M. The optimum pH value for ALP activity was about 9.2 and optimum temperature registered 45°C. ALP activity exhibited linear Arrhenius relationship at temperature greater than 44.95°C with corresponding catalytic energy of activation (Ea) = 15.23 KJ mole-1. The present study gave insights into characteristic catalytic properties of ALP extracted from L. townsendii liver.
  P.C. Chikezie
  The aim of the present in vitro study was to ascertain the tendency of two quinoline (quinine and chloroquine phosphate) drugs to interfere with osmotic stability of three human erythrocyte genotypes, namely, HbAA, HbAS and HbSS. Spectrophotometric method was used for determination of the capacity of the erythrocyte genotypes to withstand osmotic stress in the presence of separate increasing concentrations (0.2, 0.4, 0.6 and 0.8 mg%) of the two antimalarials. The Mean Corpuscular Fragility (MCF) index of the three genotypes was in the order: HbAA<HbAS<HbSS irrespective of the malaria status of the blood donors. Whereas there was no significant difference (p>0.05) between the MCF values of non-malarious blood samples of HbAA and HbAS erythrocytes, values between HbAA and HbSS erythrocytes showed significant difference (p<0.05). In addition, parasitized erythrocytes exhibited significant (p<0.05) increased MCF values. Furthermore, at relative low experimental concentrations (approx<0.4 mg %) of the two drugs, parasitized erythrocytes and those of non-malarious human origin of HbAA and HbAS genotypes showed variable levels of stability. The HbSS erythrocytes did not exhibit osmotic stability within the range of experimental concentrations of the two drugs. The implications of these findings are discussed.
  P.C. Chikezie
  The aim of the present study was to ascertain methaemoglobin concentrations and levels of NADH-methaemoglobin reductase activity of three human erythrocyte genotypes, namely, HbAA, HbAS and HbSS. The cyanomethaemoglobin reaction was used for the determination of erythrocyte haemolysate methaemoglobin concentration. NADH-methaemoglobin reductase activity was measured by the rate of oxidation of NADH + H+ when, the erythrocyte enzyme was incubated in potassium ferrocyanide {K3Fe(CN)6}. Whereas, methaemoglobin concentrations in the three erythrocyte genotypes was in the range of 1.45±0.13 to 2.50±0.43%, in the order: HbAS<HbAA<HbSS, levels of NADH-methaemoglobin reductase activity ranged between 8.86±2.49 and 14.77±1.47 IU gHb-1, in the order of: HbSS<HbAS<HbAA. However, there was no significant difference (p<0.05) in methaemoglobin concentration and NADH-methaemoglobin reductase activity between HbAA and HbAS erythrocytes. The results showed a relationship between erythrocyte NADH-methaemoglobin reductase activity and methaemoglobin concentration.
  P.C. Chikezie
  In vitro study was carried out to investigate levels of oxidative stress indicators of sickle erythrocytes incubated in aqueous extracts of Anacardium occidentale, Psidium guajava and Terminalia catappa for 12 h. At regular time intervals of 3 h, portions of the incubation mixtures were withdrawn and spectrophotometric method was used to assay for levels of erythrocyte Malondialdehyde (MDA) and methaemoglobin (Met. Hb%). The control analysis showed that within the experimental time, erythrocyte MDA increased from 2.45±0.35 to 3.13±0.59 mmol mL-1 (p>0.05; pvalue = 0.801176). Erythrocyte MDA concentrations in the presence of the three extracts were higher than the control samples at t = 3 h (p>0.05; p value = 0.963253). Compared with the control samples at the given time (t) intervals, extract of T. catappa exhibited the highest capacity to cause reduction of erythrocyte MDA ([T. catappa] = 800 mg%; [MDA] = 2.89±0.33 mmol mL-1; t = 12 h). Erythrocyte Met. Hb% increased from 2.42±0.55 to 2.51±0.49% (p>0.05; p value = 0.995171) in the control samples within 12 h. Incubation of sickle erythrocytes with extract of (P. guajava) = 800 mg% for 9 h caused reduction of Met. Hb% from 2.49±0.49 to 2.29±0.45%; p>0.05; p = 0.983519. Extracts of A. occidentale, P. guajava and T. catappa exhibited variable capacities to hinder lipid peroxidation but did not cause corresponding reduction in erythrocyte Met. Hb%, exemplified by negative correlation between the two oxidative stress indicators in the presence of T. catappa and higher concentrations of A. occidentale and P. guajava.
  C.O. Ibegbulem and P.C. Chikezie
  The serum lipid profiles of rats (Rattus norvegicus) fed with Palm Oil (PO) and Palm Kernel Oil (PKO)-containing diets were studied. Phytochemicals detected in the PO included tannins, flavonoids, saponins, cyanogenic glycosides and β-carotene while the PKO contained only tannins, flavonoids, cardiac glycosides and cyanogenic glycosides. The PO and PKO were acidic; with pH values of 5.54±0.01 and 5.85±0.01, respectively. The PO used was more (p<0.05) rancid and contained longer mono and polyunsaturated fatty acids than the PKO. Proximate compositions of the oils showed that they contained high sources of energy. Incorporating the oils at 10 mL per 100 g feed increased the lipid and energy contents of the feeds. Feeds were administered to the rats ad libitum for 35 days. The PO group (POG), PKO group (PKOG) and Control Group (CG) all drank distilled water as the only source of fluid. Consumption of the treated feeds reduced (p<0.05) daily feed intake and improved body weight gained and conversion of feed mass to body mass. The serum lipid profile of the rats showed that the POG had the highest (p<0.05) levels of triacylglycerol (TG) and Very Low Density Lipoprotein-cholesterol (VLDL-C). The PKOG had the lowest (p<0.05) high density Lipoprotein-chloesterol (HDL-C) compared to the CG and POG. It also had the highest (p<0.05) Total Cholesterol (TC): HDL-C ratio, low density lipoprotein-cholesterol (LDL-C) concentration and LDL-C: HDL-C ratio. While PO encouraged the formation of phospholipids as seen in the HDL-C, the PKO promoted the biosythensis of cholesterol as seen in the LDL-C. The study showed that PKO was more atherogenic because it was more saturated and contained fewer types of antioxidant phytochemicals.
  P.C. Chikezie , A.R. Akuwudike and C.M. Chikezie
  In vitro studies have revealed that plant extracts interfered and altered the polymerization profile of deoxygenated sickle cell haemoglobin molecules (deoxyHbS). The present study seeks to ascertain the capacity of aqueous extract of N. tabacum to alter and interfere with polymerization of deoxyHbS molecules in vitro. Spectrophotometric method was used to measure level of sodium metabisulphite induced polymerization of deoxyHbS molecule incubated in aqueous extract of N. tabacum for 180 sec. The polymerization profile of deoxyHbS molecules of control and test samples showed increasing level of polymerization with progression of experimental time. At experimental time t>30 sec, level of polymerization of control sample ranged between 60.9±0.76-100±1.05%, whereas, the test samples ranged in the following corresponding order: (N. tabacum) = 0.8 mg 100 mL-1, 65.6±0.93-176.0±4.26%, (N. tabacum) = 1.0 mg 100 mL-1, 75.7±1.07-192.9±5.03% and (N. tabacum) = 2.0 mg 100 mL-1, 135.9±5.04-297.2±19.14%. Activation of deoxyHbS polymerization by aqueous extract of N. tabacum increased in a concentration dependent manner and duration of incubation. Specifically, at t =180 sec, (N. tabacum) = 2.0 mg 100 mL-1 caused highest level of activation of deoxyHbS polymerization (197.2±19.14%); an increase in % polymerization in a ratio of 1:4.5 (approx.) compared with (N. tabacum) = 0.8 mg 100 mL-1 at t = 30 sec. The study showed that aqueous extract of N. tabacum exacerbated polymerization of deoxyHbS molecules in a concentration and time dependent manner. Therefore, N. tabacum in the present experimental form did not exhibit therapeutic potentials for management and alleviation of sickling disorder.
 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility