Buffy coat (top/bottom)- and whole-blood filtration (top/top)-produced red cell concentrates differ in size of extracellular vesicles.

BACKGROUND AND OBJECTIVES: The influence that blood component separation methods have on changes to the red blood cell membrane during storage is not well understood. In Canada, red cell concentrates (RCCs) are produced using the buffy coat (BC, top/bottom) and the whole-blood filtration (WBF, top/top) methods, and this study aimed at comparing their influence on the characteristics of the extracellular vesicles (EV) which accumulated in the respective products during storage. MATERIALS AND METHODS: Using flow cytometry, dynamic light scattering and mass spectrometry, we assessed RCC EVs for concentration, size, lipid composition and correlation with supernatant haemoglobin (Hb). RESULTS: Accumulation of RBC EVs (CD235a(+) ) with storage time was similar in WBF and BC RCCs. The size of the EVs changed from <100 nm at d5 to near 200 nm by d42, with the EVs from WBF being smaller (P < 0·001) than BC RCCs at all storage times. The amount of EV-bound Hb in the WBF and BC units was similar (about 10% of total supernatant Hb). WBF EVs and BC EVs displayed similar lipid composition. CONCLUSION: Haemolysis and EVs increase in BC and WBF RCCs during storage. Differences in the size characteristics of the EVs in WBF and BC RCCs suggest that non-RBC EVs are more prevalent in WBF products. Understanding the impact that manufacturing has on the characteristics of the different populations of EVs in RCCs will aid quality improvement efforts.

In vitro mutagenicity of anti-inflammatory parsalmide analogues PA7, PA10, and PA31 triggered by biotransformation into hydroxy derivatives.

In this study, the mutagenicity of the anti-inflammatory parsalmide [5-amino-N-butyl-2-(2-propynyloxy)-benzamide] analogues PA7 [5-amino-N-butyl-2-cyclohexyloxy-benzamide], PA10 [5-amino-N-butyl-2-phenoxy-benzamide] and PA31 [5-amino-N-butyl-2-(p-tolyloxy)-benzamide] was determined by an Ames Salmonella assay. The experiments were performed by preincubating the compounds in the absence and presence of a post-mitochondrial fraction (S9) of rat liver homogenate from phenobarbital/beta-naphtoflavone treated rats. No mutagenic effect was observed after direct testing (no S9 added) in Salmonella typhymurium strains TA98, TA100, TA102, TA1535 and TA1537. However, in the presence of S9, the test substances triggered mutagenic responses in strains TA100 and TA98. PA31 presented the strongest mutagenic potential. The reversion rates in the presence of PA31 were about 2-19 fold higher than spontaneous mutation rates. In the presence of PA7, the reversion increased 2-14-fold over spontaneous rates. While PA10 showed a relatively mild mutagenic potential, as the number of revertants did not exceed 2.5 times the number of spontaneous mutations. Mass spectrometric analysis of the in vitro biotransformation showed that S9 converted (%), regioselectively, PA7 (19%), PA10 (7%) and PA31 (12%) into hydroxy-derivatives.

Volatile compounds of cashew apple (Anacardium occidentale L.).

The volatile compounds of a largely consumed Brazilian cashew apple variety (Anacardium occidentale L. var. nanum, Anacardiaceae) were recovered by headspace extraction or simultaneous distillation-extraction. Several compounds including esters (29), terpenes (16), hydrocarbons (9), carboxylic acids (7), aldehydes (7), alcohols (3), ketones (2), lactones (2) and norisoprenoids (1) were characterized and quantified by gas chromatography-mass spectrometry analyses.

Application of high-temperature gas chromatography-mass spectrometry to the investigation of glycosidically bound components related to cashew apple (Anacardium occidentale L. Var. Nanum) volatiles.

Free and bound volatile components of a Brazilian cashew apple variety (Anacardium occidentale L. var. nanum) were obtained by simultaneous distillation-extraction (SDE) and XAD-2 adsorption. According to gas chromatography-mass spectrometry (GC-MS) analyses and retention indices, 62 free volatile constituents were characterized and quantified. They were esters (40%), terpenes (20%), hydrocarbons (14%), fatty acids (9%), aldehydes (8%), alcohols (3%), lactones (3%), ketones (1%), phenols (1%), and norisoprenoids (1%). The glycosidically bound volatile precursors were analyzed by high-temperature GC-MS, after room temperature silylation. Several conjugated alcohols and cinnamic acids were detected and reported as cashew apple glycosyl constituents for the first time.