Structural and rheological properties of diluted alkali soluble pectin from apple and carrot.

Pectin, a complex polysaccharide found in plant cell walls, plays a crucial role in various industries due to its functional properties. The diluted alkali-soluble pectin (DASP) fractions that result from the stepwise extraction of apples and carrots were studied to evaluate their structural and rheological properties. Homogalacturonan and rhamnogalacturonan I, in different proportions, were the main pectin domains that composed DASP from both materials. Atomic force microscopy revealed that the molecules of apple DASP were longer and more branched. A persistence length greater than 40 nm indicated that the pectin molecules deposited on mica behaved as stiff molecules. The weight-averaged molar mass was similar for both samples. Intrinsic viscosity values of 194.91 mL·g-1 and 186.79 mL·g-1 were obtained for apple and carrot DASP, respectively. Rheological measurements showed greater structural strength for apple-extracted pectin, whereas carrot pectin was characterized by a higher linear viscoelasticity limit. This comparison showed that the pectin fractions extracted by diluted alkali are structurally different and have different rheological properties depending on their botanical origin. The acquired insights can enhance the customized use of pectin residue and support further investigations in industries relying on pectin applications.

A mini-review on the plant sources and methods for extraction of rhamnogalacturonan I.

Rhamnogalacturonan type I (RG-I) is one of the pectin family member abundant in plant cell walls. Process of RG-I extraction from cell walls, either as a one-step or several-stage process, conditions the structure and properties of obtained polysaccharides. In this paper, we provide comprehensive overview of the factors related to the source and extraction techniques that determine the yield and chemical composition of pectin belonging to RG-I. The role of the source material, solvent, pH, temperature, time and additional factors related to applied techniques, such as microwaves, ultrasounds, high and low pressure or enzymatic treatments are discussed.

Structure and functionality of Rhamnogalacturonan I in the cell wall and in solution: A review.

Rhamnogalacturonan I (RG-I) belongs to the pectin family and is found in many plant cell wall types at different growth stages. It plays a significant role in cell wall and plant biomechanics and shows a gelling ability in solution. However, it has a significantly more complicated structure than smooth homogalacturonan (HG) and its variability due to plant source and physiological state contributes to the fact that RG-I's structure and function is still not so well known. Since functionality is a product of structure, we present a comprehensive review concerning the chemical structure and conformation of RG-I, its functions in plants and properties in solutions.

Perioperative prognostic factors in patients with ruptured abdominal aortic aneurysms treated in the intensive care unit.

BACKGROUND: The incidence of abdominal aortic aneurysm has been estimated at 20-40 cases per 100,000 per annum. The disease is often asymptomatic; in many cases, its first symptom is shock caused by a ruptured aneurysm. The aim of the present study was to assess retrospectively the selected perioperative factors in patients hospitalised in the intensive care unit (ICU) after repair of ruptured abdominal aortic aneurysm. METHODS: Analysis involved medical records of patients after repair of ruptured abdominal aortic aneurysm treated in ICU in the years 2009-2010. Patients were divided into two groups: group I - survivors who were discharged from ICU and group II - non-survivors. Demographic factors, intraoperative data, vital parameters, laboratory results and severity of patient's state on admission to ICU were analysed. RESULTS: Analysis of laboratory results on admission to ICU showed lower values of pH and HCO(3)(-) concentrations as well as higher international normalised ratio (INR) and activated partial thromboplastin time (APTT) in group II. Mean intraoperative diuresis differed between the groups; in group I - 303 mL and in group II - 155 mL. Mean diuresis on ICU day 1 was higher in group I compared to group II, i.e. 20.87 and 11.27 mL kg b.w.-1, respectively. APACHE II, SAPS II, MODS and SOFA point values were higher in group I than in group II. CONCLUSIONS: Markers of impaired homeostasis, such as pH, HCO(3)(-) concentration, INR and APTT assessed on admission to ICU can be relevant prognostic factors in patients after repair of ruptured abdominal aortic aneurysm. Monitoring of diuresis during surgery and on day 1 of ICU treatment was a sensitive risk marker for acute kidney injury. Multiple organ failure scales such as APACHE II, MODS, SOFA and SAPS II were reliable prognostic tools to be used in the early period of ICU treatment.