In vitro antioxidative activity of Fritillaria cirrhosa D. Don straw ethanolic extract and its effect on lipid, protein oxidation, and quality of Chinese-style sausage.

Fritillaria cirrhosa D. Don, which can be used for medicine and food, contains a variety of chemicals including polyphenols, alkaloids, terpenoid, and others that have beneficial biological properties like antihypertension, bacteriostasis, and anti-inflammatory. The ethanolic extract of Fritillaria straw was obtained for this study using ultrasonic-aided extraction, and the amounts of total phenols and total flavonoids were 26.56 ± 1.36 mg GAE/g dw and 18.75 ± 0.80 mg RE/g dw, respectively. Ultra-performance liquid chromatography-quadrupole time-of-flight-mass spectrometry technology was utilized to identify 50 major chemicals in the Fritillaria straw extract (FSE). Meanwhile, the antioxidative activities of FSE were evaluated by 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and Ferric reducing antioxidant power assays in vitro, which pointed out the antioxidative potential of FSE. Additionally, 0.1%, 0.5%, and 1% of FSE and 0.02% butylated hydroxyanisole (BHA) + butylated hydroxytoluene (BHT) (1:1) were separately added to Chinese-style sausage to study their effects on the lipid oxidation, protein oxidation, and quality of the sausage at different storage times. The study found that the effect of adding 1% FSE on carbonyl content, total volatile basic nitrogen, and TVC of sausage could achieve the effect of the 0.02% BHA + BHT (1:1) group on the 35th day, and the thiobarbituric acid reactive substances value and peroxide value of sausage were significantly lower than the control group. Therefore, as one of the candidates to replace synthetic antioxidants, the FSE can be used in the production of Chinese sausages, which has a positive effect on improving the product's quality and extending the shelf life. PRACTICAL APPLICATION: The antioxidative activities of 50 main compounds were identified after the ethanolic extraction of Fritillaria straw. This Fritillaria straw extract was added to Chinese sausage, effectively inhibiting the oxidation of lipids and proteins as well as the decomposition of proteins. Obviously, the Fritillaria straw extract, one of the choices to replace synthetic antioxidants, may be useful for future meat processing, because of its positive impact on the product's quality and shelf life.

[Remote sensing inversion of surface soil organic matter at jointing stage of winter wheat based on unmanned aerial vehicle multispectral]. / åŸºäºŽæ— äººæœºçš„å†¬å°éº¦æ‹”èŠ‚æœŸè¡¨å±‚åœŸå£¤æœ‰æœºè´¨å«é‡é¥æ„Ÿåæ¼”.

The rapid monitoring of soil organic matter (SOM) content in large-scale salinized wheat fields can provide data for promoting research in saline soils and carbon cycle. Based on field sampling and remote sensing images of unmanned aerial vehicle, we established remote sensing prediction models of regional SOM using three methods, i.e., multiple linear regression (MLR), partial least squares (PLSR), and support vector machine regression (SVR) for bare land and wheat field, respectively. The models were validated and compared to identify the optimal inversion model of SOM. Moreover, the SOM in the area was inverted using the optimal model, with the inversion results being compared with the data by interpolation. The results showed that the spectrum after the filtering of 5×5 median was best related to surface SOM. Among the three models, the SVR model had the highest prediction accuracy, followed by the PLSR, while the MLR lowest. The SVR model was the best one for estimating wheat field, with coefficient of determination (R2) and root mean square error (RMSE) of 0.89 and 0.20, respectively, and the validated R2 and RMSE were 0.82 and 0.24, respectively. The bare land SOM was also best fitted by the SVR model, with R2 and RMSE were 0.63, 0.26, respectively, and the verified R2 and RMSE were 0.61, 0.25, respectively, but without statistical significance. The inversion of the optimal model revealed that SOM content in this region ranged from 17.51 to 22.53 g·kg-1, with an average of 19.51 g·kg-1, which was generally consistent with the field measurement. Compared with the inversion results, the interpolation data were limited in accuracy. Overall, our study suggested that the unmanned aerial vehicle-based multi-spectral analysis could be applied to quick and accurate estimation of SOM content in saline soil at the jointing stage of winter wheat.