Food Engineering and Technology Department, Institute of Biosciences, Letters and Exact Sciences, São Paulo State University (UNESP), Cristóvão Colombo 2265, Jardim Nazareth, São José Do Rio Preto, SP, 15054-000, Brazil.
Chemical Engineering Department, Federal University of São Carlos (UFSCar), Rod. Washington Luiz, km 235, SP 310, Bairro Monjolinho, São Carlos, SP, 13565-905, Brazil.
Bioprocess Biosyst Eng. 2019 Nov;42(11):1757-1768. doi: 10.1007/s00449-019-02172-z. Epub 2019 Jul 20.
The use of Metarhizium anisopliae as a bioinsecticide is steeply increasing worldwide. However, to reduce the production costs, it is necessary to develop sophisticated techniques for conidia production. This work aimed to use a tray bioreactor to produce conidia of M. anisopliae ICB-425 in long rice and find the limiting bed depth in which the production is still viable. Experiments have been carried out to assess the influence of the air temperature and relative humidity on the spore concentration in order to determine the limiting temperature. Two scales of bioreactors in plastic packages have been used, containing 10 and 500 g of rice, and the results were similar. In the tray bioreactor, the bed depths of 2, 4 and 6 cm have been used, corresponding to the dry rice weights of 1, 2 and 3 kg, respectively, and the results were similar to the ones in plastic packages. A one-phase heat transfer model has been used to foresee the maximum temperature within the bed and the results agreed fairly well with the experimental ones. Using the model, a bed depth of 7 cm was found to be the limit for the tray bioreactor. The results obtained are very promising for the mass production of conidia of M. anisopliae at lower costs and with more effective control.
利用绿僵菌作为生物杀虫剂在全球范围内迅速普及。然而，为了降低生产成本，有必要开发出复杂的分生孢子生产技术。本研究旨在使用托盘生物反应器在长粒水稻上生产绿僵菌 ICB-425 的分生孢子，并确定仍可进行生产的限制床层深度。已经进行了实验来评估空气温度和相对湿度对孢子浓度的影响，以确定限制温度。使用了两种塑料包装的生物反应器，分别包含 10 和 500 g 的水稻，结果相似。在托盘生物反应器中，使用了 2、4 和 6 cm 的床层深度，分别对应于 1、2 和 3 kg 的干稻重，结果与塑料包装中的结果相似。使用单相传热模型预测了床层内的最高温度，结果与实验结果相当吻合。使用该模型，发现托盘生物反应器的床层深度为 7 cm 是极限。这些结果为以更低的成本和更有效的控制大规模生产绿僵菌分生孢子提供了非常有前景的途径。
