Enzymatic efficacy of some types of Aspergillus fungi isolated from some manuscripts and its effect on some of the physical and chemical properties of the manuscripts

2nd International Scientific Conference (Pure Sciences, Brilliant Creativity and Renewed Building)

Zghair, A.^1

Karbala, Iraq^1

关键词: Aspergillus flavus;    Aspergillus fungi;    Aspergillus nidulans;    Degree of crystallization;    Infrared spectrum;    Oxidation process;    Physical and chemical properties;    Strength and elongations;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/571/1/012043/pdf
DOI  :  10.1088/1757-899X/571/1/012043

来源: IOP

【 摘 要 】

The study has been conducted in the laboratory of Imam Hussein Center (peace be upon him) for the restoration and conservation of manuscripts and the care of researchers at the Imam Hussein Holy Shrine. 150 fungal isolates of Aspergillus spp. have been taken from manuscripts. Aspergillus, Aspergillus flavus, Aspergillus nidulans, Candidus,Apergillus oryzae, Apergillus niger were diagnosed. The enzymatic tests were performed to determine which species has the ability to produce analyzer of protein,cellulose, fat and starch enzymes on solid culture media of specific inspection. The results showed that Aspergillus fungi were differentiated in its production of the studied enzymes. A. nigar gave positive result for all studied enzymes with varying level of efficacy. The highest enzyme activity of this species was amylase, lipase and cellulase. However, A.oryza recorded the highest efficacy of cellulase and amylase and medium efficacy with protease. A. candidus was producing high efficacy to protease, lipase and cellulase enzymes and gave a negative test with the amylase enzyme. A.flavus was the higher efficacy with protease, lipase, cellulase enzymes and medium efficacy with amylase, while A. nidulan was recorded as the highest efficacy with protease, lipase, and cellulase enzymes and medium efficacy with amylase enzyme. The effect of growth of these fungi on the physical properties of the elongation strength, tension force and color change of paper was studied. The results showed that the effect of fungi on the manuscripts through the exposure of the damaged sample to the dark color compared to the standard sample (unaffected). The results demonstrated that the lowest values in term of tensile strength and elongation for the affected sample compared to the non-affected sample, as well as the study of their effect on the chemical properties using X-ray diffraction analysis to determine the degree of crystallization of cellulose. The results showed an increase in the crystallization of cellulose. This means a change in the chemical and mechanical properties of cellulose. In addition, the infrared spectrum was used to determine changes in the functional groups of paper observing which revealed occurring a slight decrease in the OH group as a result of the loss of water molecules from cellulose. Also, we noticed an increase in C = O absorption due to cellulose oxidation processes.