In this study, ultrasonic/microwave-assisted extraction (UMAE), microwave-assisted extraction (UAE), ultrasound-assisted extraction (UAE), and pressurized liquid extraction (PLE) were applied to extract green coffee oil (GCO), and the physicochemical indexes, fatty acids, tocopherols, diterpenes, and total phenols as well as antioxidant activity of GCO were investigated and compared. The results indicated that the extraction yield of UMAE was the highest (10.58 ± 0.32%), while that of PLE was the lowest (6.34 ± 0.65%), and linoleic acid and palmitic acid were the major fatty acids in the GCO, ranging from 40.67% to 43.77% and 36.57% to 38.71%, respectively. A large proportion of fatty acids and phytosterols were not significantly influenced by the four extraction techniques. However, tocopherols, diterpenes, total phenols, and the free radical scavenging activity were significantly different among these four GCOs. Moreover, structural changes in the coffee residues were explored by scanning electron microscopy and Fourier transform infrared spectroscopy. Overall, the high antioxidant activity of GCO demonstrated that it can be used as a highly economical natural product in the food and agricultural industries.
Bacterial resistance is eroding the clinical utility of existing antibiotics necessitating the discovery of new agents. Bacterial type II topoisomerase is a clinically validated, highly effective, and proven drug target. This target is amenable to inhibition by diverse classes of inhibitors with alternative and distinct binding sites to quinolone antibiotics, thus enabling the development of agents that lack cross-resistance to quinolones. Described here are novel bacterial topoisomerase inhibitors (NBTIs), which are a new class of gyrase and topo IV inhibitors and consist of three distinct structural moieties. The substitution of the linker moiety led to discovery of potent broad-spectrum NBTIs with reduced off-target activity (hERG IC50 > 18 μM) and improved physical properties. AM8191 is bactericidal and selectively inhibits DNA synthesis and Staphylococcus aureus gyrase (IC50 = 1.02 μM) and topo IV (IC50 = 10.4 μM). AM8191 showed parenteral and oral efficacy (ED50) at less than 2.5 mg/kg doses in a S. aureus murine infection model. A cocrystal structure of AM8191 bound to S. aureus DNA-gyrase showed binding interactions similar to that reported for GSK299423, displaying a key contact of Asp83 with the basic amine at position-7 of the linker.
Introduction: The quality of pressed walnut oil can be improved by moderate roasting treatment.Methods: This study compared physicochemical characteristics and antioxidant ability of walnut oils pressed from differently roasted pretreated walnuts, analyzed the correlation among these indicators by using Pearson correlation coefficient and correlation coefficient heatmap, and evaluated the volatile organic compounds (VOCs) of walnut oil under optimal pretreatment roasting conditions using headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS).Results: Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were able to remarkably distinguish walnut oil produced by different roasting processes. In addition, correlation analysis showed that there was a significant impact among indicators. There were 73 VOCs were identified in the optimum roasted treated walnut oil, consisting of 30 aldehydes, 13 alcohols, 11 ketones, 10 esters, 5 acids, 2 oxygen-containing heterocycles, 1 nitrogen-containing heterocycle and 1 other compound. GC-IMS results showed that aldehydes contributed significantly to the volatile flavor profile of walnut oil, especially (E)-2-heptenal, (E)-2-pentenal and hexenal.Discussion: The properties of walnut oil based on varying roasting pretreatment of walnut kernels were significantly differentiated. Roasting at 120°C for 20 min is a suitable pretreatment roasting condition for pressing walnut oil. Roasting at 120°C for 20 min is a suitable pretreatment roasting condition for pressing walnut oil.
Three varieties of safflower seed oil (SSO) from Xinjiang Autonomous Region, China, were analyzed by headspace solid‐phase micro‐extraction gas chromatography coupled with mass spectrometry (HS‐SPME‐GC‐MS) to reveal volatile components. Overall, 67 volatile components were determined and four compounds including isoamyl alcohol, caproic acid, n‐pentanal, and heptanal were newly identified in SSO as aroma‐active components. Meanwhile, 16 compounds were selected by relative odor activity value (ROAV) to evaluate contributions of single compounds to the overall odor (ROAV > 1), in which nonanal, (Z)‐6‐nonenal, and (E)‐2,4‐decadienal were the top three contributed substances (ROAV > 70). The sensory panel was described as eight definition terms (grassy, fruity, almond, mushroom, fatty, sweet, paddy, and overall fragrance). Principal component analysis (PCA) revealed a significant separation of three cultivars with the first principal component (PC‐1) and the second principal component (PC‐2) expressing 73.9% and 23.1%, respectively. Both PCA and ROAV allowed identifying the compounds positively correlated to sensory evaluation.