Pluronic f 127 powder

A 20% (w/v) solution of Pluronic F127 in saline solution was prepared by using a magnetic stirrer at 4°C overnight. The Pluronic F127 powder was purchased from Sigma-Aldrich, MO, USA.
The DBM-PF127 composite was prepared mixing DBM particles (< 80 μm) and the Pluronic F127 solution at 4°C to obtain a composite containing 40% (w/w) DBM. The composite preparation has a form of putty at the room temperature.

Essential oil from black mustard [Brassica nigra (L.) Koch] seeds was purchased from Moksha Lifestyle Products^TM (New Delhi, India) and used in the study without further purification. Two surfactants, namely, Triton X-100 and Atlas G5002, were procured from Loba Chemie Pvt. Ltd. (Mumbai, India) and Croda India Company Pvt. Ltd. (Navi Mumbai, India), respectively. Pluronic F-127 powder was purchased from Sigma-Aldrich Chemicals Pvt. Ltd. (Bangalore, India), and potato dextrose agar (PDA) powder, potato dextrose broth (PDB) powder, and resazurin sodium salt were obtained from HiMedia Laboratories Pvt. Ltd. (New Delhi, India). Oil O Red dye was supplied by Alfa Aesar, Thermo Fisher Scientific India Pvt. Ltd. (Mumbai, India). All the solvents used in the study were purchased from Merck Life Science Pvt. Ltd. (New Delhi, India) and were of AR grade.

Sodium alginate powder (80~120 cP, Wako Pure Chemical Industries, Osaka, Japan) was dissolved in deionized water at 1% (w/v). Gelatin methacrylate (GelMA), photoinitiator (lithium phenyl-2,4,6-trimethylbenzoylphosphinate, LAP) and blue light source (3 W, 405 nm) were purchased from Suzhou Intelligent Manufacturing Research Institute (Suzhou, China). GelMA was dissolved in deionized water at 2.5% (w/v), 5% (w/v) and 7.5% (w/v), and the final concentration of photoiniator was 0.25% (w/v), 0.5% (w/v) and 0.75% (w/v), respectively. Sodium alginate was dissolved in 2.5% GelMA solution at a concentration of 1% to obtain a mixed solution, which was named Alg-GelMA (1%, 2.5%) solution. Similarly, we can prepare Alg-GelMA (1%, 5%) and Alg-GelMA (1%, 7.5%) solution. Corresponding composite hydrogels can be fabricated after curing of these mixed solutions. Calcium chloride (CaCl₂) powder (Sinopharm Chemical Reagent Co., Ltd., Shanghai, China) was dissolved in deionized water at 1.5% (w/v). Collagen (CellmatrixTM Type I-A) was purchased from Nitta Gelatin Inc. (Osaka, Japan). Pluronic F-127 powder (Sigma-Aldrich, Shanghai, China) was dissolved in deionized water at 10% (w/v). Fluorescence microspheres were purchased from Aladdin Industrial Corporation (Shanghai, China). All chemicals were used without further purification.

The experiments were performed using the following polymers: polyethylene glycol 8000 (MW = 8000 Da, by Sigma-Aldrich Chemie GmbH, Deisenhofen, Germany), polyethyleneimine linear (MW = 2500 Da, by Polysciences Inc., Warrington, PA, USA), pluronic^® F-127 powder (MW = 12,600 Da, by Sigma-Aldrich Chemie GmbH, Deisenhofen, Germany), and elastamine^® RE-2000 amine (MW = 2000 Da, Huntsman Corporation, Ternate, Italy) as polyetherdiamine. All other used chemicals were purchased from Sigma-Aldrich (Sigma-Aldrich Chemie GmbH, Deisenhofen, Germany). The materials were used as received; solvents were of analytical grade. Products containing rhodamine, fluorescein sodium salt, or oil red O were stored at 4 °C in the dark.

Meloidogyne graminicola were inocubated on rice seedlings (Oryza sativa variety Nipponbare) treated with GC-7 to determine the direct effect of isolate GC-7 on the infectivity of nematodes. The roots of rice seedlings were immersed in a 50% GC-7 isolate fermentation culture (1 × 10⁹ cfu/ml) for 8 h. Roots soaked in NB medium for 8 h were used as controls. Pluronic F-127 powder (Sigma Aldrich, St Louis, United States) was added to sterile water and allowed to dissolve with stirring at 4°C for 24 h. Next, treated rice seedlings were placed in F127 gel plot, then 100 μl of M. graminicola suspension (1,000 vigorous J2s/mL) was added surrounding to each seedling. The F127 plot was incubated in greenhouse previously described. At 5 and 14 days post inoculation (dpi), the plant roots were carefully collected and stained using the NaOCl-acid fuchsin method (Bridge and Page, 1982 ). The total number of nematodes inside root galls per rice seedling was counted using a stereomicroscope (Nikon, Tokyo, Japan). The number of nematodes at different life stages was determined using a stereomicroscope to calculate their ratio and analyze the effect of GC-7 on nematode development. Each treatment had four replicates and was performed three times independently.

The preparation of hydrogel referred to the cold method that was described in a previous study [26 ]. The samples were prepared by dissolving Pluronic F127 powder that were purchased from Sigma Aldrich (St. Louis, MO, USA) at various concentrations (5%, 10%, 20%, 30%, and 40% w/v) in distilled water at 4 °C overnight to facilitate dissolution of the polymer. The samples were stored 24 h and mixed with calcium silicate cement (Union, Seoul, Korea) in 1:0.3 ratios (codes: H5, H10, H20, H30, and H40). Calcium silicate cement mixed with distilled water was used as a control (MDW).