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Osvaldo H. Campanella

Bio: Osvaldo H. Campanella is an academic researcher from Ohio State University. The author has contributed to research in topics: Starch & Viscosity. The author has an hindex of 37, co-authored 277 publications receiving 5066 citations. Previous affiliations of Osvaldo H. Campanella include Massey University & United States Department of Agriculture.


Papers
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Journal ArticleDOI
TL;DR: EDNA and other extracellular substances, acting in concert with EPS, may impact the functional properties of the matrix and the virulence of cariogenic biofilms.
Abstract: Biofilms are highly structured microbial communities that are enmeshed in a self-produced extracellular matrix. Within the complex oral microbiome, Streptococcus mutans is a major producer of extracellular polymeric substances including exopolysaccharides (EPS), eDNA and lipoteichoic acid (LTA). EPS produced by S. mutans-derived exoenzymes promote local accumulation of microbes on the teeth, while forming a spatially heterogeneous and diffusion-limiting matrix that protects embedded bacteria. The EPS-rich matrix provides mechanical stability/cohesiveness and facilitates the creation of highly acidic microenvironments, which are critical for the pathogenesis of dental caries. In parallel, S. mutans also releases eDNA and LTA, which can contribute with matrix development. eDNA enhances EPS (glucan) synthesis locally, increasing the adhesion of S. mutans to saliva-coated apatitic surfaces and the assembly of highly cohesive biofilms. eDNA and other extracellular substances, acting in concert with EPS, may impact the functional properties of the matrix and the virulence of cariogenic biofilms. Enhanced understanding about the assembly principles of the matrix may lead to efficacious approaches to control biofilm-related diseases.

222 citations

Journal ArticleDOI
TL;DR: In this paper, the authors studied the changes in the distribution of β-Lactoglobulin, α-lactalbumin, and bovine serum albumin, using one dimensional and two dimensional PAGE.
Abstract: Whey protein concentrate (WPC) solutions containing 10, 30, 60 and 120 g dry powder/kg were heated at 75°C and whey protein aggregation was studied by following the changes in the distribution of β-lactoglobulin, α-lactalbumin and bovine serum albumin, using one dimensional and two dimensional PAGE. The one dimensional PAGE results showed that a minimal quantity of large aggregates was formed when 10 g WPC/kg solutions were heated at 75°C for up to 16 min whereas appreciable quantities were formed when 30, 60 and 120 g WPC/kg solutions were similarly treated. The two dimensional PAGE analysis showed that some disulphide-linked β-lactoglobulin dimers were present in heated 10 g WPC/kg solution, but very little was present in heated 120 g WPC/kg solution. By contrast, SDS was able to dissociate monomeric protein from high molecular mass aggregates in heated WPC solution of 120 g/kg but not in 10 g WPC/kg solution heated for 30 min. The rates of loss of native-like and SDS-monomeric β-lactoglobulin, α-lactalbumin and bovine serum albumin during heating increased as the WPC concentration was increased from 10 to 120 g/kg. In 120 g WPC/kg solution heated at 75°C, the amounts of SDS-monomeric β-lactoglobulin in each sample were greater than the quantities of native-like protein. However, in WPC solutions of 10, 30 and 60 g/kg, the differences between the amounts of native-like and SDS-monomeric proteins were slight. The loss of the native-like or SDS-monomeric proteins was consistent with a first or second order reaction. In each case, the apparent reaction rate constant appeared to be concentration-dependent, suggesting a change of aggregation mechanism in the more concentrated solutions. Overall, these results indicate that in addition to disulphide-linked aggregates, hydrophobic aggregates involving β-lactoglobulin, α-lactalbumin and bovine serum albumin were formed in heated WPC solution at high protein concentration, as suggested by model studies using binary mixtures of these proteins.

129 citations

Journal ArticleDOI
TL;DR: In this article, heat-induced aggregation and gelation of β-lactoglobulin, dispersed in imidazole-HCl buffer containing 0.1 mol/dm3 NaCl at a concentration of 10% (w/v), was studied at different temperatures and pHs.

120 citations

Book ChapterDOI
01 Jan 2016
TL;DR: In this paper, the principles of thermal treatment to inactivate spoilage and pathogenic microorganisms present in foods are described in terms of the conventionally used approach, which is based on the assumption that thermal death of bacteria is exponential with time.
Abstract: The principles of thermal treatment to inactivate spoilage and pathogenic microorganisms present in foods are described in terms of the conventionally used approach, which is based on the assumption that thermal death of bacteria is exponential with time. In addition, survival parameters, notably the decimal reduction time D , are assumed to vary with temperature following either an Arrhenius-type relationship or a linear relationship, specifically when the logarithm of D is plotted as a function of temperature. Since most experimental survival curves exhibit notorious nonlinear characteristics, the currently used procedure, based on linear survival curves, has been challenged. A new approach based on the Weibull model to describe nonlinear survival curves is also presented in this article as well as a different concept focusing on the determination of survival parameters and calculation of processing times for heat treatments under nonisothermal conditions. The last part of this article describes technological advances related to batch and continuous heat treatments.

111 citations

Journal ArticleDOI
TL;DR: This review addresses theGlass transition phenomenon from a kinetics and thermodynamics standpoint by presenting existing models that are able to estimate the glass transition temperature and explores traditional and novel methods used for the characterization of the glass Transition phenomenon.
Abstract: Given the complexity in composition and the various environmental conditions to which foods and pharmaceuticals are exposed during processing and storage, stability, functionality, and quality are key attributes that deserve careful attention. Quality and stability of foods and pharmaceuticals are mainly affected by environmental conditions such as temperature, humidity, and time, and for processing conditions (e.g., shear, pressure) under which they may undergo physical and chemical transformations. Glass transition is a key phenomenon which is useful to understand how external conditions affect physical changes on materials. Consequently, theories that predict and describe the glass transition phenomenon are of a great interest not only for the food industry but also it extends to the pharmaceutical and polymer industries. It is important to emphasize that the materials of relevance in these industries are interchangeably sharing similar issues on functionality and their association with the glass transition phenomenon. Development of new materials and understanding the physicochemical behavior of existing ones require a scientific foundation that translates into safe and high-quality foods, improved quality of pharmaceuticals and nutraceuticals with lower risk to patients, and functional efficacy of polymers used in food and medicinal products. This review addresses the glass transition phenomenon from a kinetics and thermodynamics standpoint by presenting existing models that are able to estimate the glass transition temperature. It also explores traditional and novel methods used for the characterization of the glass transition phenomenon.

95 citations


Cited by
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Journal ArticleDOI
TL;DR: In this article, a review summarizes the major applications of low and high power ultrasound in food science and technology, and their methods and applications including important research results including the basic principles and applications.

818 citations

17 Jun 2015
TL;DR: A general standardised and practical static digestion method based on physiologically relevant conditions that can be applied for various endpoints, which may be amended to accommodate further specific requirements, is proposed.
Abstract: Simulated gastro-intestinal digestion is widely employed in many fields of food and nutritional sciences, as conducting human trials are often costly, resource intensive, and ethically disputable. As a consequence, in vitro alternatives that determine endpoints such as the bioaccessibility of nutrients and non-nutrients or the digestibility of macronutrients (e.g. lipids, proteins and carbohydrates) are used for screening and building new hypotheses. Various digestion models have been proposed, often impeding the possibility to compare results across research teams. For example, a large variety of enzymes from different sources such as of porcine, rabbit or human origin have been used, differing in their activity and characterization. Differences in pH, mineral type, ionic strength and digestion time, which alter enzyme activity and other phenomena, may also considerably alter results. Other parameters such as the presence of phospholipids, individual enzymes such as gastric lipase and digestive emulsifiers vs. their mixtures (e.g. pancreatin and bile salts), and the ratio of food bolus to digestive fluids, have also been discussed at length. In the present consensus paper, within the COST Infogest network, we propose a general standardised and practical static digestion method based on physiologically relevant conditions that can be applied for various endpoints, which may be amended to accommodate further specific requirements. A frameset of parameters including the oral, gastric and small intestinal digestion are outlined and their relevance discussed in relation to available in vivo data and enzymes. This consensus paper will give a detailed protocol and a line-by-line, guidance, recommendations and justifications but also limitation of the proposed model. This harmonised static, in vitro digestion method for food should aid the production of more comparable data in the future.

806 citations

Journal ArticleDOI
TL;DR: In this paper, the authors survey the research progress in hydrogen generation from liquid-phase chemical hydrogen storage materials and their regeneration, and present a review of these materials in hydrogen storage.
Abstract: In the search for future energy supplies, the application of hydrogen as an energy carrier is seen as a prospective issue. However, the implementation of a hydrogen economy is suffering from several unsolved problems. Particularly challenging is the storage of appropriate amounts of hydrogen. In this context one of the promising hydrogen storage techniques relies on liquid-phase chemical hydrogen storage materials, in particular, aqueous sodium borohydride, ammonia borane, hydrazine, hydrazine borane and formic acid. The use of these materials in hydrogen storage provides high gravimetric and volumetric hydrogen densities, low potential risk, and low capital investment because it is largely compatible with the current transport infrastructure. In this review, we survey the research progresses in hydrogen generation from these liquid-phase chemical hydrogen storage materials and their regeneration.

709 citations

Journal ArticleDOI
TL;DR: In this article, the structure of β-Lg lattice Z at 3.0 A resolution by multiple isomorphous replacement and have partially refined it (R factor=24.8%).

682 citations