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Objective： This study aimed to improve the yield and gelling property of lemon pectin. Methods: Oxalic acid was used to extract pectin from lemon residue. The factors of optimal ratio of solid-liquid, pH, extraction temperature and extraction time were optimized through single factor experiments and orthogonal experiments. The purity, degree of esterification and rheological properties of the extracted lemon pectin were analyzed. The differences of gelling property between the extracted lemon pectin and two kinds of commercial high methoxyl pectins (HMP-1, HMP-2) were compared. Results: The results showed that the yield of pectin extract was 22.83%, with total galacturonic acid of 76.06% and degree of esterification of 75.94%, when the ratio of solid-liquid was 1∶20 （g/mL）, extracting pectin at pH 2.2 and 95 ℃ for 75 min. The viscosity of the extracted lemon pectin was higher than HMP-1 and HMP-2. The calcium sensitivity was between HMP-1 and HMP-2, and the temperature sensitivity was similar to HMP-2. The sol-gel transformation of the extracted lemon pectin was found at 76.55 ℃ in the calcium ion environment. Conclusion: Lemon pectin extracted by oxalic acid has good rheological and gel properties, and can be potentially used as a stabilizer in acidic milk drinks.

Two neolignan glycosides including a new one (1), along with seven iridoid glycosides (3 − 9) and nine flavonoid glycosides (10 − 18), were isolated from the leaves of Vaccinium bracteatum. Their structures were established mainly on the basis of 1D/2D NMR and ESIMS analyses, as well as comparison to known compounds in the literature. The structure of 1 with absolute stereochemistry was also confirmed by chemical degradation and ECD calculation. Selective compounds showed antiradical activity against ABTS and/or DPPH. Moreover, several isolates also suppressed the production of ROS in RAW264.7 cells and exerted neuroprotective effect toward PC12 cells. [ABSTRACT FROM AUTHOR]

Task participants' malicious behavior can significantly reduce the credibility of mobile crowd sensing (MCS). To solve this problem, this paper proposed a data collection mechanism that analyzed and quantified participants' historical reputation according to their willingness and the quality of data they had shared, and then updated their current reputation through the logistic regression model. Simultaneously, to measure the authenticity of the collected data, the participants were divided into two types:those who were related to direct transmission of sensing data and second, those who were involved in indirect forwarding of these, which was based on the remaining transmission time of sensing data and residual energy of mobile equipment. Then the server analyzed the accuracy of data collected by participants according to the multitasking scenario. Simulation results show that the proposed mechanism can significantly improve the perceived tasks performed in real time, greatly upgrade the quality of sensing data, and effectively reduce the reward expenses.

The potato tuber moth, Phthorimaea operculella, is the most damaging potato pest in the world and is difficult to control as the larvae are internal feeders in the foliage and tubers. Entomopathogenic fungi that colonize plants as endophytes have lethal and sublethal pathological effects on insect pests. We show that Beauveria bassiana colonizes the aerial parts of potato plants endophytically after inoculation through soil drenching. Endophytic B. bassiana persisted in potato foliage for more than 50 days postinoculation. Bioassays indicated that foliage of B. bassiana‐inoculated potato plants were pathogenic against larvae of P. operculella. Sublethal experiments indicated that B. bassiana negatively affected the growth, development, and reproduction of P. operculella. Development experiments showed that the weight of P. operculella pupae reared on B. bassiana‐colonized potato plants (4.25 mg) was significantly less than that of those reared on uninoculated control plants (8.89 mg). Compared with newly eclosed larvae fed on control plants, those fed on B. bassiana‐inoculated plants had significantly lower survivorship, with only 17.8% developing to the adult stage. Oviposition of P. operculella females reared on B. bassiana endophytically colonized plants was significantly lower (35 eggs/female) than of those reared on uninoculated plants (115 eggs/female). This study demonstrates that endophytic B. bassiana can be a potential biological control agent for the control and management of P. operculella. Comparing pupal weights of P. operculella reared on potato plants inoculated with the B. bassiana strain GZGY‐1‐3 and on untreated control plants, pupae from the control plants were significantly heavier than those from treated plants. [ABSTRACT FROM AUTHOR]