Journal of Biomedical and Pharmaceutical Sciences

Two fundamental tools in thermal analysis [differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA)] using five heating rates and one DSC-Fourier Transform Infrared (DSC-FTIR) microspectroscopy using one heating rate, were used to determine the thermal characteristics and dehydration kinetics of glucose (Glc) monohydrate, maltose (Mal) monohydrate and trehalose (Tre) dihydrate in the solid state. Non-isothermal dehydration kinetics of these three sugar excipients was investigated using a model-free isoconversional Flynn–Wall–Ozawa integral method by TGA technique at different heating rates. The apparent activation energy of the dehydration kinetics was determined as: 215.7 ± 33.1, 364.9 ± 49.8 and 207.7 ± 49.4 kJ/mole for Glc monohydrate, Mal monohydrate and Tre dihydrate, respectively. The thermal-responsive changes for several specific FTIR bands in the three-dimensional FTIR spectral contour profile were observed within 50~136°C for Glc monohydrate and >95°C for Mal monohydrate in the dehydration process by the one-step DSC-FTIR microspectroscopic technique. However, two unique FTIR peaks at 1640 and 1687 cm-1 due to the bending vibrational mode of solid-like water and liquid water in the molecules of Tre dihydrate were gradually changed in the range of temperatures between 69 and 81°C during the thermal-induced dehydration process from DSC-FTIR microspectroscopic contour profile.

The effect of fibre length in a cement/fibre composite biomaterial on cement/fibre integration, ultimate compressive strength and compressive elastic modulus was investigated. Dicalcium phosphate dihydrate/ poly(lactide-co-ε-caprolactone) 75:25 was the composite material investigated, at a 25%w/w ratio. A direct relationship between increased fibre length and increasing void volume in the material was determined using micro-CT imaging and Finite Element modelling, attributed to entanglement of the fibres causing poor cement/fibre integration. This in turn was used to explain a measured decrease in the compressive strength of composites with longer fibres, from 32±2 MPa to 24±3 MPa for composites containing 400±100 μm to 1280±350 μm length fibres respectively. It was also found that the compressive elastic modulus of all cement/fibre composites was far lower than that of blank cement alone, from 1.3±0.2 GPa to 270±70 MPa. However, no correlation could be drawn between compressive elastic modulus and void volume or fibre length, as any fibre presence at the set weight ratio had a similar effect.

Chrysophyllum albidum has reputation in Nigeria as remedy for different ailments. This study evaluated the methanol extract of C. albidum stem bark for its phyto-constituents, anti-inflammatory and analgesic effects in Albino rats. Phytochemical analysis was conducted using standard procedures while the anti-inflammatory and analgesic effects were determined using formalin-induced acute paw edema and nociception in rat respectively. The results of the phytochemical screening indicated the presence of anthraquinones, steroids, tannins, alkaloids, glycosides, flavonoids, saponins and phlobatannins. The percentage inhibition of the paw oedema was calculated to be 39.09%, 37.27%, 53.63% and 62.72% for groups treated with 100 mg/kg, 200 mg/kg, 400 mg/kg body weight of methanol extract of C. albidum stem bark and diclofenac respectively, with the group treated with 400 mg/kg body weight of the extract having the highest percentage inhibition amongst the extract-treated groups. The analgesic effect was evaluated by calculating the paw-licking rate within 60 minutes after induction of oedema. The values were calculated to be 239.75 ± 13.91, 159.65 ± 11.62, 75.72 ± 5.31, 65.08 ± 9.71 and 292.04 ± 11.88 for groups treated with 100 mg/kg, 200 mg/kg, 400 mg/ kg body weight of the extract, 5 mg/kg body weight of the standard drug (diclofenac) and the negative control group (induced, but not treated) respectively. It can be concluded from the result obtained in this study that methanol extract of C. albidum stem bark contain bioactive constituents with analgesic and anti-inflammatory potentials, which goes to support its acclaimed traditional medical use of other parts of the plant in the management of pain and inflammatory conditions.

The aim of the present study was to investigate the protective role of phloretin on liver and kidney of streptozotocin (STZ) induced diabetic rats. Phloretin was used at the dose of 25 mg and 50 mg/kg b.w on STZ-induced diabetic rats to analyse the blood glucose, serum insulin, total protein, liver function enzymes and kidney function markers. Significant reduction in the levels of insulin and total protein and elevated levels of blood glucose, kidney function markers such as urea, creatinine and uric acid and increased activities of serum enzymes like alanine amino transferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) were observed in diabetic rats. Treatment of diabetic rats with phloretin ameliorate the elevated levels of glucose, activities of liver function enzymes and kidney function markers and also restore the levels of insulin and total protein to near normal. The results of this study concluded that phloretin have hepato and renal protective effects on STZ-induced diabetic rats. The present findings indicate that phloretin could be considered as therapeutic agents that can ameliorate the progression of diabetic complications.

Chrysophyllum albidum (C. albidum) has reputation in Nigeria as remedy for different ailments. This study evaluated the antimalarial potentials of methanol extract of the stem bark of C. albidum and specific Alkaline phosphatase (ALP), Alanine transaminase (ALT) and Aspartate transaminase (AST) activities in both sera and livers of Plasmodium berghei infected mice treated with methanol extract of C. albidum stem bark. The result of the phytochemical screening indicated the presence of anthraquinones, steroids, tannins, alkaloids, glycosides, terpenoides, flavonoids, saponins and phlobatannins. Percentage parasite inhibition was calculated to be 56.97%, 74.10%, 85.26% and 92.83% for groups treated with 200 mg/kg, 400 mg/kg, 600 mg/kg body weight of the methanol extract of C. albidum stem bark and 5 mg/kg body weight of Chloroquine (standard drug) respectively. It was observed that, the specific ALP, ALT and AST activities in both sera and liver samples of the group infected but not treated were significantly higher (p<0.05) than the infected and treated groups. There was significant difference (p<0.05) in the specific ALP, ALT and AST activities between groups treated with 5 mg/kg body weight of Chloroquine and 600mg/kg body weight of the methanol extract of C. albidum stem bark. However, there was no significant difference (p<0.05) in the specific ALP, ALT and AST activities between the groups treated with 200 mg/kg and 400 mg/kg body weight of methanol extract of C. albidum stem bark. The ability of the methanol extract of C. albidum stem bark to inhibit parasite multiplication/progression may be attributed to the presence of various bioactive constituents such as flavonoids, tannins, alkaloid or saponins and further support the ethno medicinal claim of the use of other parts of the plant in the treatment of malaria.