Search results for "Arid"

Fluorescence and color as markers for the Maillard reaction in milk–cereal based infant foods during storage

2007

Abstract Free and total fluorescence compounds and color formation were measured in three different milk–cereal based infant foods stored at 25, 30 and 37 °C for 9 months to evaluate the advanced and final stages of the Maillard reaction. Milk–cereal infant foods containing honey (B) or fruits (C) had fluorescent values higher than sample (A) without them. This difference could be ascribed to the higher monosaccharide (fructose and/or glucose) content of (B) and (C), which could increase susceptibility to the Maillard reaction. However, for color increase (ΔE), no significant differences (p

Diagnostic use of monoclonal IgG antibody to meningococcal B polysaccharide in cerebrospinal fluid

1986

Depressed Prostaglandin Release from Peritoneal Cells Induced by a T Cell Adjuvant, Lentinan

1979

Abstract PGE and PGF release from peritoneal exudate cells was studied in mice after injection with two s (1–3) glucans, the antitumor active lentinan and the inactive pachyman. 4 days after injection of both polysaccharides, the spontaneous and phagocytosis-induced PGE and PGF release was markedly suppressed. However, only the immunopotentiator lentinan induced peritoneal exudate cells which exhibited a longer lasting diminished PG release. The data suggest that the T cell adjuvant lentinan may potentiate cellular immune responses by reducing synthesis of immune suppressive prostaglandins from peritoneal exudate cells.

Control of end-of-life oxygen-containing groups accumulation in biopolyesters through introduction of crosslinked polysaccharide particles

2021

The formulation of bio-based materials with good performance in service and controlled end-of-life is imperative for an effective circular economy. In this work, an innovative approach to induce and control the end-of-life of biodegradable polyesters through introduction of crosslinked polysaccharide particles is proposed. Chitosan (Ch) has been subjected to ionotropically crosslinking and then added to polylactic acid (PLA) at different amounts (1.0–4.0%w) by melt mixing. All obtained results suggest that the addition of crosslinked Ch (cCh) particles does not modify significantly the investigated biopolyester properties. Specifically, the thermal analysis of the composites reveals that th…

Effect of konjac glucomannan addition on aroma release in gels containing potato starch.

2014

International audience; The present study aimed to measure the retention of aroma compounds (ethyl acetate, ethyl hexanoate and carvacrol) in dispersions based on konjac glucomannan and/or potato starch, and to highlight the influence of konjac glucomannan on the mechanisms involved in aroma retention. Publications on the effect of konjac glucomannan on aroma release are scarce. Konjac glocomannan is a polysaccharide used as a food additive for its viscous and emulsifying properties. Retention of aroma compounds in dispersions was calculated from partition coefficients which were measured using the phase ratio variation method. This method, consisting of analyses of the headspace at equilib…

ChemInform Abstract: The Allyl Ester as Carboxy-Protecting Group in the Stereoselective Construction of Neuraminic Acid Glycosides.

1989

The application of the allyl-ester moiety as protecting principle for the carboxy group of N-acetylneuraminic acid is described. Peracetylated allyl neuraminate 2 is synthesized by reacting the caesium salt of the acid 1 with allyl bromide. Treatment of 2 with HCl in AcCl or with HF/pyridine gives the corresponding 2-chloro or 2-fluoro derivatives 3 and 4, respectively (Scheme 1). In the presence of Ag2CO3, the 2-chloro carbohydrate 3 reacts with di-O-isopropylidene-protected galactose 5 to give the 2–6 linked disaccharide with the α-D-anomer 6a predominating (α-D/β-D = 6:1; Scheme 2). Upon activation of the 2-fluoro derivative 4 with BF3 · Et2O, the β-D-anomer 6b is formed preferentially (…

1991

Über die autoxydation ungesättigter verbindungen. IV. Mitt. Die autoxydation des 2.3-dimethylbutadiens (1.3) und des 10.12-octadecadiensäuremethylest…

1955

Die spontane Autoxydation des Dimethylbutadiens, die zu polymeren Peroxyden fuhrt, wird kinetische verfolgt und mit der Autoxydation des konjugierten 10, 12-Octadecadiensauremethylesters verglichen. Beide Reaktionen verlaufen autokatalytisch. Die Reaktionsgeschwindigkeit ist zu Beginn der Wurzel aus dem Autoxydationsgrad (Mol O2/Mol Substrat) proportional. Die gebildeten Peroxyde zerfallen monomolekular in kettenstartende Radikale. Die Brutto-aktivierungsenergieen werden angegeben. Die Einwirkung von Azodiisobuttersaurenitril, Ascaridol, Di-tert.-Butylperoxyd und Cu++ -oktoat auf die Autoxydation des 10,12-Octadecadiensauremethylesters wird untersucht. Es ergibt sich, das auch die Autoxydat…

Il clima nell'isola? Tende all'aridità, lo dicono le variabili pioggia e temperatura

2007

Long-term decrease in Asian monsoon rainfall and abrupt climate change events over the past 6,700 years

2021

Significance The variability of the Asian summer monsoon (ASM) is important for the functioning of ecological and societal systems at regional to continental scales, but the long-term evolution and interannual variability of this system is not well understood. Here, we present a stable isotope–based reconstruction of ASM variability covering 4680 BCE to 2011 CE. Superimposed on a gradual drying trend, a rapid drop in mean annual precipitation (>40%) toward persistently drier conditions occurred in ∼1675 BCE. This megadrought caused regional forest deterioration and enhanced aeolian activity affecting Chinese ecosystems. We argue that this abrupt aridification starting ∼2000 BCE triggered wa…