Lian Huida,Qin Cheng,Zhang Cong,Yan Minfei,Li Hongbing,Zhang Suiqi
Aims Lanthanum, a rare earth element, is used in agriculture and forestry to promote plant growth and productivity. We aimed to investigate its role in altering the roots and alleviating P deficiency in the adzuki bean Vigna angularis . Methods The adzuki bean variety “Jin No. 5” was pre-cultivated in sand. Fourteen-day-old seedlings were sprayed twice with 0.4 mM LaCl 3 solution. Next, we treated the seedlings with half-strength Hoagland solution containing P reduced to 1% of its original concentration (P-deficient); P reduced to 5% of the original (P-marginal); and unadjusted solution (P-sufficient). We measured plant growth, root structure, root hydraulic conductivity, P content, gas exchange, and photosynthetic pigment levels in all groups. Results LaCl 3 application significantly increased leaf P concentration, effectively improving the P uptake efficiency of roots, shoots, and leaves under severe P stress. Root morphology and acid phosphatase (APase) activity varied significantly in response to LaCl 3 under low-P stress. A greater leaf area, gas exchange ability, chlorophyll content, and carotenoid content were observed in the presence of LaCl 3 under P-marginal stress. Conclusions The application of LaCl 3 can promote growth and P acquisition in adzuki beans under P limitation by inducing changes in root morphology, APase activity, and hydraulic conductivity.
Muhammad Mazhar,Zhu Yong,Wen Anyan,Liu Na,Qin Likang
Regular consumption of low-glycemic index (GI) foods is a common strategy for type 2 diabetes patients. To evaluate the potential application of adzuki beans in low-GI foods, the phenolic profile and alpha-amylase inhibitor (α-AI) activity of four varieties of adzuki beans (G24, Te Xiao Li No. 1, Gui Nong No. 1, and Qian Xiao Hei) were determined. The starch digestibility properties and in vitro glycemic index (IVGI) of these beans were also evaluated using the in vitro digestion model coupled with 3,5-dinitrosalicylic acid colorimetry. The results indicated that these adzuki beans, containing numerous phenolics, showed inhibitory activities to alpha-amylase with the α-AI activities between 1.760 ± 0.044 and 3.411 ± 0.186 U/g. The resistant starch (RS) contributed predominantly to the total starch with proportions between (69.78 ± 2.45%) and (81.03 ± 0.06%); Te Xiao Li No. 1 was the highest compared with the other varieties. The adzuki beans were categorized into low- or medium-GI foods, and the IVGI ranged from (39.00 ± 0.36) to (56.76 ± 4.21). These results suggested that adzuki beans can be used as a component of low-GI foods.
Herein, a novel peptidyl probe is first synthesized by the amide reaction between glutathione-capped gold nanoclusters (GSH-AuNCs) and positive charged arginine-rich peptide (Arg 9 ), and it is called Arg 9 -GSH-AuNCs. Polyuridylic acid (polyU), as a polyanion , is firstly used to induce the aggregation-induced emission enhancement (AEE) of positive charged Arg 9 -GSH-AuNCs through electrostatic attraction . The peptide bond on the carboxyl terminal of the arginine residues can be recognized and cleaved by trypsin. Hence, polyU is hard to induce the aggregation of peptidyl probe again, and the AEE from GSH-AuNCs becomes weak. It is an ideal platform to detect trypsin and screen trypsin inhibitors . The fluorescent peptidyl probe exhibits excellent sensitivity for trypsin. A good linear range of trypsin is obtained from 1 to 50 ng·mL −1 with the limit of detection (LOD) 0.31 ng·mL −1 , which is lower than those of most reported works. Furthermore, the inhibitory effects of the extracts from foods (i.e., soybean seed flour, black soybean seed flour, mung bean seed flour, and azuki bean seed flour) on the trypsin activity have been studied. The half maximal inhibitory concentration (IC 50 ) values of extracts from soybean seed flour, black soybean seed flour, mung bean seed flour, and azuki bean seed flour are 4.5, 9.3, 11.6, 20.9 μg·mL −1 , respectively. The screening results show that these extracts from foods all have inhibitory effects on trypsin. Among them, the extract from soybean seed flour exhibits significant inhibitory effect.