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The present study aims to investigate the effect of copper (as CuSO4, 5H2O) supply (0, 25 and 50 μM) on performance of cilantro (Coriandrum sativum L.) plants grown under hydroponic conditions. All applied Cu concentrations drastically reduced the biomass production, length of the shoots and the roots and disturbed the ions (Cu, Ca, Fe, Zn and Mg) homeostasis. Either Cu-starvation (0 μM) or Cu-toxicity (25 and 50 μM) significantly reduced the net photosynthetic rate, stomatal conductance and transpiration rate resulting in reduced water use efficiency. Under Cu-toxicity, the variations in gas exchange parameters were associated with a remarkable decline in the photosynthetic pigments including Chlorophyll a, Chlorophyllb, Chlorophyll (a + b) and carotenoids. Additionally, an enhanced lipid peroxidation (evaluated as Malondialdehyde (MDA) contents) with a concomitant increase in proline, total soluble sugars and melanoidins contents were observed under these conditions. The increased MDA levels resulted in decrease in total lipid content and alteration of the fatty acid profiles in both shoots and roots with a general tendency toward the accumulation of saturated fatty acids that mirrors a decline in the desaturases activity. Although the increased activity of enzymatic antioxidants including catalase (CAT), gaiacol peroxidase (GPX) and ascorbate peroxidase (APX), the oxidative-induced injuries caused by 25 and 50 μM Cu were found to be irreversible and the optimal growth parameters were not achieved.

In a stricter legislative context, greener detergent formulations are developed. In this way, synthetic surfactants are frequently replaced by bio-sourced surfactants and/or used at lower concentrations in combination with enzymes. In this paper, a LC-MS/MS method was developed for the identification and quantification of enzymes in laundry detergents. Prior to the LC-MS/MS analyses, a specific sample preparation protocol was developed due to matrix complexity (high surfactant percentages). Then for each enzyme family mainly used in detergent formulations (protease, amylase, cellulase, and lipase), specific peptides were identified on a high resolution platform. A LC-MS/MS method was then developed in selected reaction monitoring (SRM) MS mode for the light and corresponding heavy peptides. The method was linear on the peptide concentration ranges 25-1000 ng/mL for protease, lipase, and cellulase; 50-1000 ng/mL for amylase; and 5-1000 ng/mL for cellulase in both water and laundry detergent matrices. The application of the developed analytical strategy to real commercial laundry detergents enabled enzyme identification and absolute quantification. For the first time, identification and absolute quantification of enzymes in laundry detergent was realized by LC-MS/MS in a single run. Graphical Abstract Identification and quantification of enzymes by LC-MS/MS.

International audience; The effects of feeding bees artificial sugars and/or proteins on the sugar compositions and (13)C isotopic measurements of royal jellies (RJs) were evaluated. The sugars fed to the bees were two C4 sugars (cane sugar and maize hydrolysate), two C3 sugars (sugar beet, cereal starch hydrolysate), and honey. The proteins fed to them were pollen, soybean, and yeast powder proteins. To evaluate the influence of the sugar and/or protein feeding over time, samples were collected during six consecutive harvests. (13)C isotopic ratio measurements of natural RJs gave values of around -25 ‰, which were also seen for RJs obtained when the bees were fed honey or C3 sugars. However, the RJs obtained when the bees were fed cane sugar or corn hydrolysate (regardless of whether they were also fed proteins) gave values of up to -17 ‰. Sugar content analysis revealed that the composition of maltose, maltotriose, sucrose, and erlose varied significantly over time in accordance with the composition of the syrup fed to the bees. When corn and cereal starch hydrolysates were fed to the bees, the maltose and maltotriose contents of the RJs increased up to 5.0 and 1.3 %, respectively, compared to the levels seen in authentic samples (i.e., samples obtained when the bees were fed natural food: honey and pollen) that were inferior to 0.2% and not detected, respectively. The sucrose and erlose contents of natural RJs were around 0.2 %, whereas those in RJs obtained when the bees were fed cane or beet sugar were as much as 4.0 and 1.3 %, respectively. The combination of sugar analysis and (13)C isotopic ratio measurements represents a very efficient analytical methodology for detecting (from early harvests onward) the use of C4 and C3 artificial sugars in the production of RJ.