Emulsion formation and stabilization by biomolecules: the leading role of cellulose

Emulsion stabilization by native cellulose has been mainly hampered because of its insolubility in water. Chemical modification is normally needed to obtain water-soluble cellulose derivatives. These modified celluloses have been widely used for a range of applications by the food, cosmetic, pharmaceutic, paint and construction industries. In most cases, the modified celluloses are used as rheology modifiers (thickeners) or as emulsifying agents. In the last decade, the structural features of cellulose have been revisited, with particular focus on its structural anisotropy (amphiphilicity) and the molecular interactions leading to its resistance to dissolution. The amphiphilic behavior of native cellulose is evidenced by its capacity to adsorb at the interface between oil and aqueous solvent solutions, thus being capable of stabilizing emulsions. In this overview, the fundamentals of emulsion formation and stabilization by biomolecules are briefly revisited before different aspects around the emerging role of cellulose as emulsion stabilizer are addressed in detail. Particular focus is given to systems stabilized by native cellulose, either molecularly-dissolved or not (Pickering-like effect).Financially support by the Portuguese Foundation for Science and Technology, FCT, via the projects PTDC/AGR-TEC/4814/2014, PTDC/ASP-SIL/30619/2017 and researcher grant IF/01005/2014. RISE Research Institutes of Sweden AB and PERFORM, a competence platform in Formulation Science at RISE, are acknowledged for additional financing. This research has been supported by Treesearch.se.info:eu-repo/semantics/publishedVersio

'Mediterranean' dietary pattern for the primary prevention of cardiovascular disease

It is well established that diet plays a major role in cardiovascular disease risk. The traditional Mediterranean dietary pattern is of particular interest because of observations from the 1960s that populations in countries of the Mediterranean region, such as Greece and Italy, had lower mortality from cardiovascular disease compared with northern European populations or the US, probably as a result of different eating habits. This review assessed the effects of providing dietary advice to follow a Mediterranean-style dietary pattern to healthy adults or people at increased risk of cardiovascular disease in order to prevent the occurrence of cardiovascular disease and reduce the risk factors associated with it. Definitions of a Mediterranean dietary pattern vary and we included only randomised controlled trials (RCTs) of interventions that reported at least two of the following components: (1) high monounsaturated/saturated fat ratio, (2) low to moderate red wine consumption, (3) high consumption of legumes, (4) high consumption of grains and cereals, (5) high consumption of fruits and vegetables, (6) low consumption of meat and meat products and increased consumption of fish, and (7) moderate consumption of milk and dairy products. The control group was no intervention or minimal intervention. We found 11 RCTs (15 papers) that met these criteria. The trials varied enormously in the participants recruited and the different dietary interventions. Four trials were conducted in women only, two trials were in men only and the remaining five were in both men and women. Five trials were conducted in healthy individuals and six trials were in people at increased risk of cardiovascular disease or cancer. The number of components relevant to a Mediterranean dietary pattern ranged from two to five and only seven trials described the intervention as a Mediterranean diet. The largest trial, which recruited only postmenopausal women and was not described as a Mediterranean diet meeting only two of the criteria described above, reported no difference in the occurrence of cardiovascular disease between the dietary advice group and the control group. The other trials measured risk factors for cardiovascular disease. As the studies were so different, it was not possible to combine studies for most of the outcomes. Where it was possible to combine studies, we found small reductions in total cholesterol levels as well as in the harmful low-density lipoprotein (LDL) cholesterol concentrations. The reductions in total cholesterol were greater in the studies that described themselves as providing a Mediterranean diet. None of the trials reported side effects. The review concludes that, from the limited evidence to date, a Mediterranean dietary pattern reduces some cardiovascular risk factors. However, more trials are needed to look at the effects of the different participants recruited and the different dietary interventions to see which interventions might work best in different populations

Etiikkaa historiantutkijoille

Satu Lindman, Anu Koskivir­ta ja Jari Eilola (toim.) Historian­tutkimuksen etiikka. Gaudea­mus 2017

Perspectives on the Lindman Hypothesis and cellulose interactions

In the history of cellulose chemistry, hydrogen bonding has been the predominant explanation when discussing intermolecular interactions between cellulose polymers. This is the general consensus in scholarly textbooks and in many research articles, and it applies to several other biomacromolecules’ interactions as well. This rather unbalanced description of cellulose has likely impacted the development of materials based on the processing of cellulose—for example, via dissolution in various solvent systems and regeneration into solid materials, such as films and fibers, and even traditional wood fiber handling and papermaking. In this review, we take as a starting point the questioning of the general description of the nature of cellulose and cellulose interactions initiated by Professor Björn Lindman, based on generic physicochemical reasoning about surfactants and polymers. This dispute, which became known as “the Lindman hypothesis”, highlights the importance of hydrophobic interactions in cellulose systems and that cellulose is an amphiphilic polymer. This paper elaborates on Björn Lindman’s contribution to the subject, which has caused the scientific community to revisit cellulose and reconsider certain phenomena from other perspectives.info:eu-repo/semantics/publishedVersio

Simultaneous treatment of SO2 containing stack gases and waste water

A process for simultaneously removing sulfur dioxide from stack gases and the like and purifying waste water such as derived from domestic sewage is described. A portion of the gas stream and a portion of the waste water, the latter containing dissolved iron and having an acidic pH, are contacted in a closed loop gas-liquid scrubbing zone to effect absorption of the sulfur dioxide into the waste water. A second portion of the gas stream and a second portion of the waste water are controlled in an open loop gas-liquid scrubbing zone. The second portion of the waste water contains a lesser amount of iron than the first portion of the waste water. Contacting in the openloop scrubbing zone is sufficient to acidify the waste water which is then treated to remove solids originally present