A Study to Evaluate Aflatoxin Contamination in Food from Gauteng Province

The sugar industry has been facing some problems with white sugar intended for soft drinks production. Some studies have been demonstrated the sugar could be source of insoluble substances technically called by Acid Beverage Flocs (ABF). It appears during the beverage production; however, the flocs are easily disappearing with shaking. This may be related to raw material the sugarcane quality and, consequently, with the efficiency of the juice clarification process, since if there is no adequate juice treatment. The sugarcane commonly has lower quality and higher intensity of impurities, such as proteins, wax, minerals and colloids. The sugar industries are implementing solutions to reduce the amount of impurities through using technologies like ionic resins to removal of color, odor or undesirable taste. It could transform raw sugar in refined or white sugars. The aim of this work was evaluate the efficiency of purification of sugar solution with chromatographic adsorption system. We observed that the color reduction was around 69% and an intensive reduction in turbidity of sugar aqueous solution. There were variation on sucrose and increase on reducing sugars (glucose and fructose) contents. It is possible to conclude that the process could be efficient to reduce the color (MAU color), turbidity and ABF into sugar solutions.

Mycotoxins are potentially dangerous contaminants of livestock feeds. In this study, we measured the levels of fumonisin B1 and glycated fumonisin B1 in feedstuffs and then investigated the ability of the extrusion heating regimen to convert the most prevalent mycotoxin contaminant, fumonisin B1 , to a less toxic glycated form. All feed samples were analyzed with fully validated methods. All measured concentrations of fumonisin B1 were below harmful thresholds, including European Union-recommended levels or US Food and Drug Administration action levels.

Because fumonisin B1 was highly contaminated mycotoxin in our present investigation and fumonisin B1 has been shown to be less toxic following Maillard type reaction with reducing sugar, we examined the formation of fumonisin B1 derivatives by Maillard reaction under extrusion process conditions. We employed a variety of tandem mass spectrometric methodologies to selectively detect fumonisin B1 derivatives and to elucidate their structures partially. We found that compounds of m/z 736 were more likely artifacts or side reaction products rather than glycation products. N-(carboxymethyl) fumonisin B1 of m/z 780 and other major glycation products of m/z 794 and 810 were not detected, and only negligible amounts of methylene fumonisin B1 was found in 10 extruded feed samples. Therefore, either the tested extrusion conditions did not induce fumonisin B1 glycation or the glycation products simply could not be detected by the method employed in this study.

The aims of this study were to determine HMF level in some foods and to reduce their level by biodegradation. Coffee whitener, cappuccino, hot chocolate, instant coffee, instant powdered mix (coffee, coffee whitener and sugar) and aromatized cocoa were subjected to HMF analysis in the scope of this study. The HMF determination of samples was carried out using a high performance liquid chromatography. Color properties of the samples were determined according to standard procedures and their relations with HMF content were also investigated. The biological degradation of HMF with lactic acid bacteria was also studied with broth media and a model food system (reconstituted milk).The average HMF levels were 12.59 mg/kg for coffee whitener, 572.49 mg/ kg for cappuccino, 660.29 mg/kg for hot chocolate, 1804.91 mg/kg for instant coffee, 871.56 mg/kg for instant powdered mix and 980.94 mg/kg for aromatized cocoa. The addition of lactic acid cultures reduced the HMF content of the samples. HMF levels of broth media and model food inoculated with lactic acid bacteria (L. lactis, L.bulgaricus, L. cremoris) decreased about 25 % as a result of HMF biodegradation.

When the banana (Musa paradisiaca) peel was subject of enzymatic hydrolysis with cellulase and hemicellulase, only glucose was obtained. Images from banana peel, using confocal laser scanning microscopy, demonstrate that the cellulose is the main structural compound. Fatty acids, phenolic and other compounds were detected from the organic residual extract, and characterized by means of NMR, FT-IR and UHPLC-MS techniques. The presences of these compounds were corroborated through a steam distillation. Under this condition, banana peel could have potential applications in the food field, where could be used to improve some procedures such as the obtaining of banana vinegar.

Fractionation is an effective technology to maximize the utilization of lignocelluloses for the production of chemicals and materials. In this case, bamboo was subjected to a two-step fractionation process based on the concept of biorefinery: (a) formic acid treatment at boiling point under atmospheric pressure for 2 h, and (b) post treatment with alkaline hydrogen peroxide solution containing 1% NaOH and 1% H2 O2 at 80 ºC. The combination of formic acid delignification and alkaline hydrogen peroxide degradation achieved an effective removal of both lignin (delignification rate 94.9%) and hemicelluloses (removal rate 87.4%) from bamboo, producing cellulose rich pulp, formic acid lignin and sugars. To investigate the structural modification of lignin during the fractionation process, the residual lignin in the treated samples was isolated and characterized with multiply techniques including gel permeation chromatography, pyrolysis gas chromatography mass spectrometry, Fourier-transform infrared spectroscopy, etc. The relative ratio of S/G was 1.63 for bamboo milled wood lignin (L1), whereas the lignin isolated from the formic acid treated cellulose-rich fraction (L2) presented a chromatograph similar to that of L1 but had a lower S/G ratio of 1.28. This indicated that a preferential removal of S units during the formic acid fractionation process. In addition, alkaline hydrogen peroxide treatment resulted in more removal of S units, as indicated by a lower S/G ratio of 0.71.

Volatile Organic Compounds (VOCs) profile of foods obtained by Gas Chromatography/Mass Spectrometry (GC/MS) can be considered a potent tool of food products quality changes occurring as a result of different processing, such as ripening and deterioration. The aim of the present study was the evaluation of volatiles profiles of peaches (cv Springcrest) during their storage in conditions similar to those of long distance transport that normally these products undergo before being placed on market. We investigated control sample (no stored fruit) and peaches stored in cardboard boxes wrapped in heat-sealed HD polythene bags, both in normal and modified atmosphere (0% and 23% CO2 ) after 1 and 8 days of storage at 4°C. GC/MS analysis of these samples allowed the identification of a total of 115 VOCs.

The comparison of the VOCs profile of the three peach samples (control, normal atmosphere and 23% CO2 ) shows that fruits packaged in normal atmosphere released a greater amount of esters of medium chain fatty acids, such as ethyl nonanoate and ethyl dodecanoate. On the other hand, fruits stored in normal atmosphere and modified atmosphere after 8 days of storage (increased concentration of CO2 in packs) released a greater amount of esters of long chain fatty acids, such as ethyl hexadecanoate.

The conversion of lignocellulosic biomass into biofuel and biomaterial is promising for the substitution of fossil resources in energy and material applications. Given the complexity of plant cell wall, the main challenge is to obtain lignocelluloses with high yield and purity. For a better understanding of lignocellulosic biomass, chromatography stands out as a powerful separation method that can support the lab directed research and pilot scale production of biomaterial and biochemical. This paper provides a review on the characterization of cellulose, hemicellulose and lignin along with their derivatives and decomposed sugar monomers, in particular their isolation and purificationmethods using various specific types of chromatography. Methods with various specific types of chromatography. This review also summarizes different chromatographic methods for obtaining the molecular weights of cellulose, hemicellulose and lignin that have been used in recent years, and highlights future opportunities for the application of those biopolymers.

Proteomics is very important component in the era of post-genomics because it can address functions of genes and some important non-gene-determined biological issues such as Post Translational Modifications (PTMs), splicing, translocation, and spatial structure. Proteome is very complex, including multiple parameters such as kind of proteins, copy number of each protein, PTMs, isoforms, spatial structure of each protein, protein-protein interaction, and protein-other molecule interaction, etc. Moreover, proteome is dynamic, and alters with different conditions such as different physiological processes, different pathological processes, and different disease status.

A novel, simple and economic reverse phase High Performance Liquid Chromatography (RP-HPLC) method has been developed for the quantification of Imatinib in bulk and capsule dosage form with greater precision and accuracy. Separation was achieved on Analytical technologies, C-18, (250mm*4.6mm) column in isocratic mode with mobile phase consisting of acetonitrile: potassium dihydrogen phosphate buffer (pH 2.5) (30:70v/v) with a f low rate of 0.8 mL/min. The detection was carried out at 268 nm. The retention time of Imatinib was found to be 2.67 min. The method was validated as per ICH guidelines. Linearity was established for Imatinib in the range 5-35 μg / ml with r2 value 0.996. The percentage recovery of Imatinib was found to be in the range 99.49-99.67 %. The high recovery and low relative standard deviation confirm the suitability of the proposed method for the estimation of the drug in bulk and capsule dosage forms. Validation studies demonstrated that the proposed RP-HPLC method is simple, specific, rapid, reliable and reproducible for the determination of Imatinib for quality control level.

I started off my career as a biotechnologist in the early eighties, of the last century, using mainly size exclusion chromatography to identify biologically active substances, from ovine broncho alveolar macrophages co-cultured with lymphocytes, from the lungs of young sheep infected with Jaagsiekte Retrovirus (JSRV)