Same authors. The mass spectrum for peak c exhibited a key fragment at m/z 447, revealing a group of orientin isomers which, in line with the literature, could possibly be identified as 8-O-methyl-7-hydroxyaloin [47,84] or luteolin-6-C-glucoside [13]. Peaks d and e showed a most important fragment at m/z 433. It has been reported that Aloe vera extracts include aloin-derived diastereoisomers for instance 5, 7 or 10-hydroxyaloin, which were proposed for the tentative identification of these peaks [13,47,48,76,85]. Similarly, peaks f, g, h and j had been tentatively identified as dihydroisocoumarin glucoside [84], 6 -malonylnataloin B [47,48], six -malonylnataloin A [47,48] and 5,3 -dihydroxy-6,7,4 -trimethoxyflavone [48], respectively. Lastly, peak i showed a most important fragment at m/z 585. A compound with 585 g mol-1 of molecular weight was also discovered by A barro-Ortega et al. [13], despite the fact that its molecular structure was not determined.Table 6. Tentative identification of unknown phenolic compounds in AVE by HPLC-MS. Peak 1 a b c d tR 2 (min) ten.9 13 13.8 15.2 (m/z) [M-H]455 337 609 447 447 433 433 433 433 433 433 505 459 459 585 343 Elemental Composition C16 H17 O-Tentative Identification Unknown cis or trans 5-p-Coumaroylquinic acid luteolin-6,8-C-diglucoside 8-O-methyl-7-hydroxyaloin luteolin-6-C-glucoside 7-hydroxyaloin B 10-hydroxyaloin B 5-hydroxyaloin B 7-hydroxyaloin A 10-hydroxyaloin A 5-hydroxyaloin A Dihydroisocoumarin glucoside 6 -malonylnataloin B six -malonylnataloin A Unknown 5,3 -Dihydroxy-6,7,4 trimethoxyflavoneRef. [13] [13] [13] [47,84] [13] [47] [13,48,76,85] [13] [47] [13,48,76,85] [13] [84] [47,48] [47,48] [13] [48]e f g h i j15.FGF-21 Protein Storage & Stability 9 17.7 20.two 20.eight 24.two 24.C27 H29 O16 C22 H23 O10 C22 H23 O10 C21 H21 O10 C21 H21 O10 C21 H21 O10 C21 H21 O10 C21 H21 O10 C21 H21 O10 C24 H25 O12 C23 H23 O10 C23 H23 O10 C18 H15 O7 -Notation for peak identification refers to Figure 4. two Retention times from HPLC-MS according to extracted ion chromatograms (EICs).three.4. Scanning Electron Microscopy (SEM) SEM was used to investigate the impact on the MAE method around the AVS structure.AGR3 Protein web Figure 5a,b show SEM micrographs obtained for raw AVS after drying and grinding measures also as for AVS residue obtained just after MAE beneath optimal conditions, respectively.PMID:23775868 A considerable transform in the surface morphology on the AVS particles was observed. Before extraction, particles exhibited a reasonably smooth and unaltered surface. However, right after MAE, AVS showed improved porosity and evidenced surface deterioration. These benefits are in accordance with other authors reporting related effects of microwave irradiation on diverse vegetal components such as cocoa bean shell [5], Pinus radiata bark [87] and brown seaweeds [88]. In all instances, it was recommended that the damage for the vegetal structure can facilitate solvent penetration, enhancing diffusion and extraction of bioactive compounds, which aids to boost TPC and antioxidant activity values.Antioxidants 2022, 11,extraction, particles exhibited a reasonably smooth and unaltered surface. However, right after MAE, AVS showed improved porosity and evidenced surface deterioration. These final results are in accordance with other authors reporting similar effects of microwave irradiation on diverse vegetal materials for example cocoa bean shell [5], Pinus radiata bark [87] and brown seaweeds [88]. In all instances, it was suggested that the harm towards the vegetal structure can 21 of 25 facilitate solvent penetration, enhancing diffusion and extraction of bioactive compoun.