Safari Marzieh, Motamedi Elaheh, Kari Dolatabad Hossein, Modarres Sanavy Seyed Ali Mohammad
Department of Agronomy, Tarbiat Modares University, Tehran, Iran.
Department of Nanotechnology, Agricultural Biotechnology Research Institute of Iran (ABRII), Agricultural Research, Education and Extension Organization (AREEO), Karaj, Iran.
Heliyon. 2020 Oct 20;6(10):e05076. doi: 10.1016/j.heliyon.2020.e05076. eCollection 2020 Oct.
In order to develop nanotechnology application in the agricultural systems achieving more sustainability in the environment, we have used different nano-carriers for phosphate solubilizing bacteria. The viability and efficacy of two bacterial species; (PP20) and (PK11) in solubilizing phosphate sources (i.e., tricalcium phosphate and hydroxyapatite) with different nano-carriers including nanoclay, natural char micro-particles (NCMPs), nanoclay + alginate, NCMPs + alginate, and natural char nano-particles (NCNPs)+alginate were investigated. Clay, talc powder, and natural char (NC) were included for comparison. The synthesized NCNPs and NCMPs were characterized using FTIR, SEM and Boehm titration analyses. The results confirmed that the chemical oxidation of pristine char made many oxygenated functional groups on the surface of tiny and spherical NCNPs (14.8 nm) which caused their effective incorporation in the matrix of alginate beads. Results of phosphate solubilizing study showed that was the superior species for viability and stability of its performance on solubilizing phosphorus. The six months evaluation showed that NCNPs + alginate and nanoclay + alginate carriers at both temperatures (4 °C and 28 °C), were the proficient carriers for preserving both bacteria. The results of solubilizing phosphorus sources revealed that both bacteria solubilized tricalcium phosphate more than hydroxyapatite and PK11 showed more privilege in this regard. In addition, the solubilizing index determined after storage for 6 months at 4 °C was higher for all the carriers. Analysis of variance for phosphatase activity revealed that embedding both bacteria in nanoclay + alginate carrier guaranteed the highest phosphatase activity, even though differences between this carrier and NCNPs + alginate and NCMPs + alginate were not significant for the PK11.
为了在农业系统中开发纳米技术应用以实现更高的环境可持续性，我们将不同的纳米载体用于解磷细菌。研究了两种细菌（PP20和PK11）在使用包括纳米黏土、天然炭微颗粒（NCMPs）、纳米黏土+海藻酸盐、NCMPs+海藻酸盐以及天然炭纳米颗粒（NCNPs）+海藻酸盐等不同纳米载体溶解磷源（即磷酸三钙和羟基磷灰石）方面的活力和功效。纳入黏土、滑石粉和天然炭（NC）作为对照。使用傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）和 Boehm 滴定分析对合成的NCNPs和NCMPs进行了表征。结果证实，原始炭的化学氧化在微小的球形NCNPs（14.8纳米）表面产生了许多含氧官能团，这使得它们能够有效地融入海藻酸盐珠粒的基质中。磷溶解研究结果表明，PP20在溶解磷的活力和性能稳定性方面是更优的菌种。六个月的评估表明，在两种温度（4℃和28℃）下，NCNPs+海藻酸盐和纳米黏土+海藻酸盐载体是保存两种细菌的有效载体。磷源溶解结果表明，两种细菌溶解磷酸三钙的能力均强于羟基磷灰石且PK11在这方面更具优势。此外，在4℃下储存6个月后测定的所有载体的溶解指数均更高。磷酸酶活性的方差分析表明，将两种细菌包埋在纳米黏土+海藻酸盐载体中可确保最高的磷酸酶活性，尽管对于PK11而言，该载体与NCNPs+海藻酸盐和NCMPs+海藻酸盐之间的差异并不显著。
