Combined Methods (combined + methods)

Distribution by Scientific Domains


Selected Abstracts


PRESERVATION OF "UMBU" (SPONDIAS TUBEROSA ARRUDA CÂMARA) PULP IN THE GREEN STAGE OF MATURATION BY COMBINED METHODS

JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2007
ELIDA CONCEIÇÃO JORGE
ABSTRACT "Umbu" (Spondias tuberosa Arruda Câmara) is a typical fruit from northeastern Brazil of considerable economic importance to this region, because several products are derived from it and commercialized, especially the pulp, which can be used as a raw material for preserves and juices. The objective of this research was to study the preservation of umbu in the green stage of maturation by combined methods, including heat treatment and the addition of preservatives and sucrose. The pulps were blanched, pasteurized and mixed with the preservatives and sucrose according to a complete factorial design with three variables (ratio pulp/sucrose, potassium sorbate and sodium metabisulfite), two levels and two repetitions. The products were filled into high-density polyethylene packages and exposed to a temperature of 40C for 120 days. Physicochemical, color and chemical (SO2) analyses showed that the concentrations of sodium metabisulfite and potassium sorbate used did not significantly alter product quality. The addition of sucrose significantly decreased the water activity and led to intense browning. The microbiological evaluations showed good product stability for 120 days. The overall results indicated that the heat treatment applied was effective if high levels of hygiene were maintained during the preparatory stages and the packaging materials were well sanitized. The combined preservation methods appear to be an economic way to preserve these high-acid pulps. [source]


Natural Antioxidants Preserve the Lipid Oxidative Stability of Minimally Processed Avocado Purée

JOURNAL OF FOOD SCIENCE, Issue 5 2005
Pedro Elez-Martinez
ABSTRACT: Lipid oxidation is one of the major phenomena that limit the shelf-life of avocado products. The effects of adding 100 ppma-tocopherol, 200 ppm ascorbic acid, and 200 ppm ethylenediaminetetraacetic acid (EDTA) on he stability of the lipidic fraction of minimally processed avocado purées were evaluated throughout storage. , tocopherol, followed by ascorbic acid, reduced oil rancidity processes during storage. Peroxide formation was minimal when a-tocopherol was added to avocado pulp, prolonging the induction stage of oils for at least 12 wk. When preserved in vacuum, iodine and specific extinction coefficient at 270 nm (k270) values were more stable, with changes of 5.87 g I2/100 g oil and 0.237, respectively, during 24 wk. On the other hand, EDTA was not shown to be effective in preserving the stability of the lipid fraction of avocado preserved by combined methods. [source]


71 Proteomics of haematococcus pluvialis: new opportunities for study of genomics of a non-sequenced species

JOURNAL OF PHYCOLOGY, Issue 2003
Q. Hu
The green alga, Haematococcus pluvialis, has become a model organism for commercial production of the high-value carotenoid astaxanthin. H. Pluvialis has also drawn significant scientific attention because fundamental biological questions relating to the massive cellular accumulation of astaxanthin have to be addressed in order to improve the yield and quality of the algal biomass. However, research has been impeded by the lack of molecular background information on this non-sequenced species. A combination of classical biochemistry with a state-of-the-art proteomic approach was used to address these questions. This was possible by taking advantage of information already available for homologous genes/gene-products in organisms whose genomes have been sequenced. The approach involved isolation of subsets of the proteome from subcellular compartments/organelles of an organism by one- or two-dimensional electrophoresis (1-DE or 2-DE) and their identification by N-terminal sequencing and peptide mass fingerprinting (PMF), involving matrix-assisted laser desorption/ionization and time-of-flight (MALDI-TOF) mass spectrometry coupled with bioinformatics. Based upon the information obtained from the combined methods, expression and physiological functions of specific genes/encoded proteins may be deduced. Examples include profiling of cell wall proteins, biogenesis and protein composition of lipid bodies, and expression patterns of soluble proteins under stress conditions. Advantages and limitations of the method for non-sequenced organisms and for cross-species protein identification will also be discussed. [source]


Optimization of metagenomic DNA extraction from activated sludge samples

ASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2009
Yuan-Yuan Qu
Abstract Metagenomic DNA extraction is essential for metagenomic technology. Therefore, optimization of a conventional total DNA extraction from activated sludge was investigated in detail in this study. Throughout two distinct orthogonal experiments, it was shown that the highest yield for metagenomic DNA could be obtained using TENP buffer, lysozyme of 1 mg ml,1 (1 h), protease K (200 µg ml,1), SDS (1%, 1 h). Furthermore, the quality of the differentially extracted DNA was subsequently assessed by the molecular fingerprint technology, such as denaturing gradient gel electrophoresis (DGGE) and ribosomal intergenic spacer analysis (RISA). The results indicated that the microbial diversity was dramatically different by different combined methods, and the DNA template quality for RISA was much better than that for polymerase chain reaction (PCR)-DGGE. This study provides detail process for metagenomic DNA extraction of activated sludge, and it would be useful for metagenomic DNA extraction of other environment samples. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd. [source]