A comparative study of physicochemical, proximate and minerals analysis of some underutilized wild edible seeds used as condiments in Nigerian traditional soups

The present study focused on Physicochemical, proximate and mineral analysis of some underutilized wild edible seeds (Parkia biglobosa, Prosopis africanum and Acacia sieberiana) used as condiments in Nigerian traditional soup and consumed by different tribal communities across the country. The seed samples were all pulverized and their properties determined appropriately. The physicochemical properties of the three seed samples were comparable with each other and the values obtained were similar and fell within the range observed for similar seeds and powdered samples used as condiments or for industrial purposes. Swelling and solubility profiles of the seed samples were quite high and reflected the high water absorption capacity of the pulverized seeds. Proximate analysis of the seed samples revealed a high protein content especially for P. africanum and A. siberiana while P. biglobosa had a high fat and carbohydrate content. Elemental analysis of the pulverized seeds was also carried out to determine the mineral contents and it was observed that the concentration of the essential elements were within safety limits while the heavy metals were very low with lead and chromium absent in two of the samples which was an indication of little or no toxicity of the seeds. The results of the various analysis carried out on the seed samples p\shows that all the three (3) study seeds are safe for consumption. These lend credence to their use as condiments and indicates that they can be further explored for other uses in the food industry.

Evaluation of the phase solubility of inclusion complexes of diisopropylphenol (INN) with hydroxypropyl-β-cyclodextrin

The paper presents the results of a study of the stability of aqueous solutions of inclusion complexes of hydroxypropyl-β-cyclodextrin with diisopropylphenol in various systems by the Higuchi-Connors phase solubility method. The phase solubility profiles for each system corresponding to the AN type are determined graphically, and the stability constants of the resulting inclusion complexes are calculated. An aqueous solution containing 0.2 % Tween 80 and 0.2 % mannitol was selected as the optimal condition for obtaining the hydroxypropyl-β-cyclodextrin inclusion complex with diisopropylphenol.

N1-Benzofused Modification of Fluoroquinolones Reduces Activity Against Gram- Negative Bacteria

<p>The fluoroquinolone class of antibiotics have a well-established structure-activity relationship (SAR) and a long history in the clinic, but the effect of electron-rich benzofused substituents at the N1 position remains poorly explored. Groups at this position are part of the topoisomerase-DNA binding complex and form a hydrophobic interaction with the major groove of DNA. Molecular modelling techniques were employed to select benzofused substituents that were shown to enhance this interaction of fluoroquinolones for the DNA gyrase target. Seven N1-modified fluoroquinolones were synthesised and tested against a panel of Gram-negative pathogens to determine minimum inhibitory concentration (MIC) values. Gram-negative outer membrane penetration was investigated using the membrane permeabiliser polymyxin B nonapeptide (PMBN) and the target affinity of representative compound <b>6e</b> was determined in a cell-free environment. A correlation between N1 substituent hydrophobicity and activity was observed across the MIC panel, with compound activity decreasing with increased hydrophobicity. Those compounds with highest hydrophobicity were inactive due to poor solubility profiles whereas compounds with intermediate hydrophobicity were inactive due to impaired outer membrane penetration and reduced inhibition for the DNA gyrase target, the latter in contrast to modelling predictions. This study adds new information to the fluoroquinolone SAR and suggests limited utility of large hydrophobic substitution at the N1 position of fluoroquinolones.</p>

N1-Benzofused Modification of Fluoroquinolones Reduces Activity Against Gram- Negative Bacteria

<p>The fluoroquinolone class of antibiotics have a well-established structure-activity relationship (SAR) and a long history in the clinic, but the effect of electron-rich benzofused substituents at the N1 position remains poorly explored. Groups at this position are part of the topoisomerase-DNA binding complex and form a hydrophobic interaction with the major groove of DNA. Molecular modelling techniques were employed to select benzofused substituents that were shown to enhance this interaction of fluoroquinolones for the DNA gyrase target. Seven N1-modified fluoroquinolones were synthesised and tested against a panel of Gram-negative pathogens to determine minimum inhibitory concentration (MIC) values. Gram-negative outer membrane penetration was investigated using the membrane permeabiliser polymyxin B nonapeptide (PMBN) and the target affinity of representative compound <b>6e</b> was determined in a cell-free environment. A correlation between N1 substituent hydrophobicity and activity was observed across the MIC panel, with compound activity decreasing with increased hydrophobicity. Those compounds with highest hydrophobicity were inactive due to poor solubility profiles whereas compounds with intermediate hydrophobicity were inactive due to impaired outer membrane penetration and reduced inhibition for the DNA gyrase target, the latter in contrast to modelling predictions. This study adds new information to the fluoroquinolone SAR and suggests limited utility of large hydrophobic substitution at the N1 position of fluoroquinolones.</p>

Investigation of possible solubility and dissolution advantages of cocrystals, I: Aqueous solubility and dissolution rates of ketoconazole and its cocrystals as functions of pH

Since there are conflicting reports in the literature on solubility and dissolution advantages of cocrystals over free forms, we systematically studied solubility and intrinsic dissolution rates of a weakly basic drug, ketoconazole, and its cocrystals with fumaric acid and succinic acid as functions of pH to determine what advantages cocrystals provide. pH-solubility profiles were determined in two different ways: one by lowering pH of ketoconazole aqueous suspensions using HCl, fumaric acid and succinic acid, and the other by adjusting pH of cocrystal suspensions using respective coformer acids or NaOH. Similar pH-solubility profiles were obtained whether free base or cocrystals were used as starting materials to determine solubility. With the addition of fumaric and succinic acids to aqueous suspensions of free base to lower pH, the maximum solubility (pHmax) was reached at pH ~3.5-4.0, below which the solubility decreased and cocrystals formed. The solubility, however, continued increasing when HCl was added to ketoconazole suspension as no cocrystal or salt was formed. During determination of cocrystal solubility, a conversion to free base was observed when pH was raised above pHmax. Thus, pH-solubility profiles of cocrystals resembled solubility profiles commonly encountered with salts. Above pHmax, both free base and cocrystal had similar solubility under identical pH conditions; the solubility of cocrystal was higher only if the pH differed. In contrast, intrinsic dissolution rates of cocrystals at pH>pHmax under identical bulk pH were much higher than that of free ketoconazole since cocrystals had lower microenvironmental pH at the dissolving surface, where the solubility was high. Thus, cocrystals of basic drugs can potentially provide higher dissolution rates under intestinal pH conditions.

Protein concentrates obtained from pig by-products using pH-shifting technique: a preliminary study

ABSTRACT: This study aimed to investigate the extraction and characterization of protein concentrates from pig by-products (heart, liver and kidneys) using the pH-shifting technique. From the solubility profiles (pH 2 to 12), the protein extraction was performed at alkaline pH (10.0 to 11.5), obtaining two fractions: soluble (SC) and insoluble (IC). Higher protein content (71 to 77%) and extractability (214 to 459 mg/g) were observed in heart and liver concentrates; whereas, for water holding capacity (WHC) the highest values (4.20 to 4.54 g water/g protein) were for the heart (SC) and kidney (SC and IC) concentrates. All concentrates had high emulsion stability and higher WHC than commercial protein extenders (whey and soybean). The concentrates obtained from the soluble fraction were redder (higher a* values and lower h values) and darker (lower L* values) than insoluble fraction, especially heart and liver concentrates. Use of concentrates in sausage production slightly altered the color chroma (C*) of samples. It was concluded that the pig by-products protein concentrates had great potential of use as extenders in sausage production.