Study On The Anti-mildew Performance Of Rhizoma Corydalis Compound Nano-TiO₂ On Bamboo

Traditional bamboo mildew inhibitors not only pollute the environment and endanger human health,but also easily lose efficacy.Forest product industry urgently needs a kind of green,non-toxic,broad-spectrum and long-term mildew inhibitor.Many components of Chinese herbal medicine have excellent efficacy and environmental protection value in inhibiting microorganisms.Compounding with nano-TiO₂can improve its slow-release and loss-resistance performance,and make bamboo have more functions,it is expected to replace chemical mildew inhibitors containing copper,chromium,arsenic,etc.1.Five kinds of organic solvents were used for Soxhlet extraction of Rhizoma Corydalis,and the mixed molds of Aspergillus niger,Penicillium citrinum and Trichoderma viride were used as the target to carry out the anti-mildew test.The results showed that the ethanol extract of Rhizoma Corydalis had the best anti-mildew effect,and the toxic limit concentration was 0.10g/m L;the toxic limit concentration of 80%ethanol extract of Rhizoma Corydalis to Aspergillus niger was 0.09g/m L.The seven solvent extracts of Rhizoma Corydalis were detected by HPLC-MS.it was concluded that the components with molecular weight of 336.4,338.4 and 353.4 played an important role in the prevention of mold.2.Nano-TiO₂ was prepared by sol-gel method,calcined at 4 grades of temperature,XRD was used to analyze the crystal form and particle size.The anti-mildew test showed that the mixture of nano-TiO₂powder and ethanol extract of Rhizoma Corydalis could achieve good anti-mildew effect.Added the ethanol extract of Rhizoma Corydalis into the preparation process of nano-TiO₂,created two new composite methods--composite sol and powder.The composite powder has long time dispersion stability.The sustained-release property of the compound mildew inhibitors were detected by UV spectrophotometer.FTIR,SEM and EDS were used to detect and analyz the mildew inhibitors and modified bamboo samples.3.The results of bamboo mildew prevention test showed that the composite sol and composite powder with the concentration of 0.5g/m L reached the toxic limit concentration of bamboo mildew,and the prevention effect was equivalent to 7%ACQ-3.After 30 days of aging test,the results showed that the composite sol,composite powder and four kinds crystalline of nano-TiO₂treatment could effectively improve the anti ultraviolet effect of bamboo.