Effects of a super-absorbent polymer derived from poly-γ-glutamic acid on water infiltration, field water capacity, soil evaporation, and soil water-stable aggregates

The poly-γ-glutamic acid super-absorbent polymer (γ-PGA SAP) is an environmentally friendly material. Five different γ-PGA SAPs contents based on weight, including 0% (CK), 0.05% (T1), 0.10% (T2), 0.15% (T3), and 0.20% (T4), were added to the soil in this study. The results showed that cumulative infiltration decreased by 32.4% (T1), 39.2% (T2), 51.0% (T3), and 52.0% (T4) at 90 min and the field capacity was increased by 18.7% (T1), 26.0% (T2), 37.8% (T3), and 58.3% (T4) compared with the CK. The cumulative evaporation of the different treatments with γ-PGA SAPs was 17.1% (T1), 23.5% (T2), 24.4% (T3), and 25.3% (T4) higher than that of the CK at the end of the evaporation experiment. The evaporation experiment lasted 96 h (CK), 132 h (T1), 144 h (T2), 180 h (T3), and 312 h (T4) to progress from field capacity to a soil water content of 10%. Adding γ-PGA SAPs to the soil significantly increase the water-stable aggregate content below 0.25 mm when the γ-PGA SAP addition exceeded 0.10%. So reasonable utilization of γ-PGA SAP can improve water use efficiency and improve soil structure in semi-arid areas.</p

Primer sequences used for quantitative real time RT-PCR.

Primer sequences used for quantitative real time RT-PCR.</p

AT1aR knockout improved epididymal histomorphology induced by high fat diet.

A, B: Body weight of rats was recorded weekly and body weight gain was calculated by weight increase in 12 weeks. C. Daily food intake of rats. D: Physical morphology of epididymal fat. E: Epididymal fat index (showed as epididymal fat weight/body weight). F: Adipocytes morphology was visualized by HE staining and adipocyte area were calculated by Image J. *p +p -/—ND rats; Ψp < 0.05 vs WT-ND rats. Data were presented as Mean ± S.E.M. n = 6.</p

sgRNA primer sequences for AT1aR^-/- rats generation.

sgRNA primer sequences for AT1aR-/- rats generation.</p

AT1aR deficiency did not cause alterations of AT1bR and AT2R in adipose tissue.

A. Gene expression of AT1bR in adipose tissue. B. Protein expression of AT2R in adipose tissue. Data were presented as Mean ± S.E.M. n = 4. (TIF)</p

Development of AT1aR^-/- rats.

A. sgRNA combined CRISPR/Cas system to generate AT1aR-/- rats. B, C. PCR results for AT1aR-/- rats and WT rats. M: marker; N: negative control; P: positive control D. AT1aR deficiency was confirmed in major Ang II responsive tissues. Data were presented as Mean ± S.E.M. n = 5. (TIF)</p

AT1aR knockout improved insulin resistance and metabolic disorders in high-fat diet rats.

A: Oral glucose tolerance test (OGTT) curve and area under the curve. B: Insulin tolerance test (ITT) curve and area under the curve. C: Fasting blood glucose (FBG). D: Blood pressure. E: Serum triglyceride (TG) levels. F: Serum total cholesterol (T-CHO). G: Serum free fatty acids (NEFAs). H: Serum glycerol. I: Serum low-density lipoprotein (LDL). J: Serum high-density lipoprotein (HDL). *p #p < 0.05 vs WT-HFD rats. Data were presented as Mean ± S.E.M. n = 6.</p

AT1aR knockout activated cAMP/PKA pathway.

A: Protein expressions of PKA, P-GSK-3β (ser9) and GSK-3β in adipose tissue. B: cAMP levels in adipose tissue. C: The proposed pathway for Ang II inhibiting adipose lipolysis. By binding to AT1R, Ang II activates inhibitory Gi which in turn reduces cAMP production. As a result, PKA activation is limited and HSL phosphorylation is decreased, leading to inhibitory of triglyceride hydrolysis. +p -/—ND rats. Data were presented as Mean ± S.E.M. n = 6.</p

Poly-γ-glutamic acid enhances the wheat yield, water use efficiency and soil physicochemical properties of the arid area in the Northwest China

Poly-γ-glutamic acid (γ-PGA) is an environment-friendly super absorbent polymer that can be used as a soil conditioner, which is promising to improve crop productivity and cope with soil degradation. The objectives of this study are to study the effects of γ-PGA on soil physicochemical properties and winter wheat (Triticum aestivum L. cv. Xinong 975) production in arid region of Northwest China. According to the mass ratio of γ-PGA and soil, experiment treatments consisted of four different γ-PGA application rates, which were designated as 0 (CK), 0.05% (P0.05), 0.1% (P0.1), and 0.15% (P0.15), respectively. The mixed soil samples were uniformly filled into identical plastic pots. Each treatment had three replicates randomly distributed within 12 pots. The results indicated that γ-PGA significantly increased saturated water content by 6.3-11.5%, field capacity by 8.4-15.3%, and plant available water by 5.1-12.5% compared with the CK. γ-PGA increased soil NO3−-N content and residue, and enhanced the proportions of soil macro-aggregates compared with the CK. γ-PGA increased winter wheat yield by 29.3-34.7%, and WUE by 21.2-33.3% compared with the CK. The main conclusion γ-PGA application amount of 0.05-0.1% can be used to improve soil physicochemical properties and winter wheat production in degraded soil.</p

High fat diet activated Ang II-AT1R axis in rats.

A. Protein expressions of kinases downstream of the Ang II-AT1R axis, p38 and ERK. B. Gene expression of Nox4 in adipose tissue. *p < 0.05 vs WT-ND rats. Data were presented as Mean ± S.E.M. n = 4.</p