Celloto Valéria R, Oliveira Arildo J B, Gonçalves José E, Watanabe Cecília S F, Matioli Graciette, Gonçalves Regina A C
Departamento de Farmácia, Universidade Estadual de Maringá, Avenida Colombo 5790, Maringá, PR, Brazil.
ScientificWorldJournal. 2012;2012:495970. doi: 10.1100/2012/495970. Epub 2012 May 1.
While many natural and synthetic compounds exhibit auxin-like activity in bioassays, indole-3-acetic acid (IAA) is recognized as the key auxin in most plants. IAA has been implicated in almost all aspects of plant growth and development and a large array of bacteria have been reported to enhance plant growth. Cells of Klebsiella oxytoca isolated from the rhizosphere of Aspidosperma polyneuron and immobilized by adsorption on different inorganic matrices were used for IAA production. The matrices were prepared by the sol-gel method and the silica-titanium was the most suitable matrix for effective immobilization. In operational stability assays, IAA production was maintained after four cycles of production, obtaining 42.80 ± 2.03 μg mL(-1) of IAA in the third cycle, which corresponds to a 54% increase in production in relation to the first cycle, whereas free cells began losing activity after the first cycle. After 90 days of storage at 4°C the immobilized cells showed the slight reduction of IAA production without significant loss of activity.
虽然许多天然和合成化合物在生物测定中表现出类似生长素的活性，但吲哚 - 3 - 乙酸（IAA）被认为是大多数植物中的关键生长素。IAA几乎涉及植物生长和发育的各个方面，并且据报道大量细菌可促进植物生长。从多脉白坚木根际分离并通过吸附固定在不同无机基质上的产酸克雷伯菌细胞用于生产IAA。基质通过溶胶 - 凝胶法制备，硅钛是最适合有效固定的基质。在操作稳定性试验中，经过四个生产周期后仍保持IAA的产量，在第三个周期获得42.80±2.03μg mL(-1)的IAA，相对于第一个周期产量增加了54%，而游离细胞在第一个周期后开始失去活性。在4°C储存90天后，固定化细胞显示IAA产量略有下降，但活性没有明显损失。
