Comprehensive characterisation of phenolics from Nitraria sibirica leaf extracts by UHPLC-quadrupole-orbitrap- MS and evaluation of their anti-hypertensive activity

Biology and morphometric relationship of gall inducers Contarinia sp. and corresponding parasitoids for swollen galls of Nitraria sibirica pall

Galls function as provide shelter for gall inducers, guarding them against their natural enemies. Previous research has illuminated the interactions between galls, gall inducers, and their corresponding parasitoids within various caltrop plants. However, less is known about these relationships within Nitraria sibirica, particularly regarding the efficacy of parasitism. Therefore, this study aimed to identify the morphometric relationships among the swollen galls, gall inducers, and their parasitoids. Two species of gall inducers and three species of parasitoids were obtained from the swollen galls of N. sibirica. The correlations of the parasitization indexes, the lifespan of gall inhabitants, and temperature and the morphometric relationships between the galls and their inhabitants were analyzed. The dominant gall inducer identified was Contarinia sp. (Diptera: Cecidomyiidae). Furthermore, it was observed that three solitary parasitoids attacked Contarinia sp. in the swollen galls, with only Eupelmus gelechiphagus acting as an idiobiont ectoparasitoid. The dominant parasitoids were Platygaster sp. and Cheiloneurus elegans at sites 1 and 2, respectively, with Platygaster sp. displaying greater abundance than C. elegans in the swollen galls. The lifespan of the gall inhabitants shortened gradually as the temperature increased. Moreover, the optimal number of gall chambers ranged from two to four per swollen gall with maximized fitness, which can be considered the optimal population density for the gall inducer Contarinia sp. Morphometric analysis exhibited a strong linear correlation between gall size and chamber number or the number of gall inhabitants, as well as a weak correlation between gall size and body size of the primary inhabitants of swollen galls. Our results highlight the importance of the biological investigation of parasitoids and gall inducers living in closed galls with multiple chambers and may pave the way for potential application in biological control.

Polysaccharides from Nitraria retusa Fruit: Extraction, Purification, Structural Characterization, and Antioxidant Activities

Polysaccharides are important bioactive components of Nitraria retusa fruit (NRF). In this study, the ultrasonic-assisted extraction (UAE) conditions of polysaccharides from Nitraria retusa fruit (NRFPs) were optimized by response surface methodology (RSM). The structural characteristics and antioxidant activity were investigated. The maximum NRFPs yield of 3.35% was obtained under the following optimal conditions: temperature of 59.5 °C, time of 30.5 min, liquid-to-solid ratio of 19.5 mL/g. Three polysaccharide fractions, NRFP-1 (20.01 kDa), NRFP-2 (28.96 kDa), and NRFP-3 (67.45 kDa), were isolated. Glucose, galactose, and arabinose in different percentages were identified as the primary monosaccharide units. The Fourier transform infrared spectrometer (FT-IR) and nuclear magnetic resonance (NMR) analysis indicated the presence of α- and β-glycosidic bonds in NRFPs. The NRFP-3 exhibited the highest scavenging activities against DPPH, ABTS, -OH free radicals, and Fe⁺³-reducing activity.

Non-volatile compounds of Hyssopus cuspidatus Boriss and their antioxidant and antimicrobial activities

Hyssopus cuspidatus is a famous spice and an aromatic vegetable. Few information could be available concerning its non-volatile chemical composition and bioactivities. Preliminary bioactive evaluations on the crude ethanol extract and its four fractions disclosed that the ethyl acetate fraction (EAF) exhibited antioxidant and antimicrobial bioactivities. LC-MS/MS analysis of EAF helped to identify sixty-four compounds, and phenolic compounds were the dominant components. Systematic separation and purification of EAF led to the isolation of thirty-four compounds. Six compounds were identified to be new and eighteen compounds were discovered from H. cuspidatus for the first time. Rosmarinic acid, methyl rosmarinate, butyl rosmarinate and salvigenin were the major components of EAF and their contents were determined. Most of isolated compounds exhibited significant or moderate antioxidant and antimicrobial activities. This research supported the edible application of H. cuspidatus and disclosed the potency of it as a natural antioxidant and antimicrobial food additive.