lily Givar; Bita Sodaei; Sepideh Hamedi
Abstract
Book and documents damaged or contaminated by microorganisms are a serious threat to the health of users and librarians. This research was aimed to identify the different species of fungi in the archive of museums and their effects on manuscripts and also reviewing the possibility of transferring them ...
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Book and documents damaged or contaminated by microorganisms are a serious threat to the health of users and librarians. This research was aimed to identify the different species of fungi in the archive of museums and their effects on manuscripts and also reviewing the possibility of transferring them to employees or vice versa. Method: Current research was conducted in a field experiment. First the manuscripts (Aldoa, Resale Haj and Kholase Alfieh) were examined based on the visual effects of the fungal deterioration, then sampling was performed to cultivate and identify fungi under sterile conditions. Sabouraud dextrose agar medium was used for cultivation and finally, after 10 to 14 days, directs smears were prepared from grown colonies, and fungal genera were identified. the fungi were identified based on microscopic and morphological properties. The results of the studies showed that the fungi on the paper works in the archives of the Malek museum include Aspergillus flavus, Cladosporium, Acremonium, Trichophyton schoenleinii and Sterile hyphae, respectively. Aspergillus, Cladosporim and Acremonium fungi are common allergenic fungi which are identified in the libraries and can cause lung allergies in human. So these fungi can be dangerous for people who suffer from tuberculosis or background lung diseases. T.schoenleinii fungus is a pathogenic fungus in humans and is not common in books. This pathogenic fungus can be probably transferred to the manuscript by one of the librarians or a person who has frequently accessed to this book. Sterile hyphae are usually scattered in the surrounding and are not worth diagnosing and pathogenic.
Biodegradation
pardis yousefi; Sepideh Hamedi; Esmaeil Rasooly Garmaroody; mojtaba koosha
Abstract
Bio-refinery includes technologies which can convert biomass resources to valuable products. In this study, carboxymethylation of the xylan-rich hemicelluloses extracted from sugarcane bagasse pith was performed. DS of the carboxymethyl xylan (CMX) was determined 0.68 using ICP-OES analysis. The presence ...
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Bio-refinery includes technologies which can convert biomass resources to valuable products. In this study, carboxymethylation of the xylan-rich hemicelluloses extracted from sugarcane bagasse pith was performed. DS of the carboxymethyl xylan (CMX) was determined 0.68 using ICP-OES analysis. The presence of absorption bands at 1580 and 1311 cm-1 in the FTIR spectrum of the modified xylan are associated to the stretching vibration of C-O bonds of carboxymethyl groups. The carboxymethyl xylan/chitosan (CMX/CS) films were then prepared by casting method. XRD pattern showed that the intensity of the characteristic peaks of the chitosan reduced after film preparation which may be due to decreasing the crystalline nature of the film. SEM images showed that the surface of the film is uniform. The observed exothermic peak in DSC thermograms showed that the films degraded at higher than 200oC. Water vapor permeability (WVP) of the carboxymethyl xylan/chitosan film was measured 0.84± 0.1 g mm/m2 h kPa. Colorimetric analysis proved that the white index (WI) of the CMX/CS film increased as compared with xylan/chitosan film. In contrary, the yellow index (YI) of the CMX/CS film decreased. Swelling ratios of the CMX/CS and xylan/CS films were measured as 130.42 and 95.71 respectively. The prepared CMX/CS films exhibited higher tensile strength in compared to xylan/chitosan film. This may be resulted from the interactions between amine groups of chitosan and carboxyl groups of CMX. CMX/CS film exhibited the higher antibacterial activity against E. coli that S. aureus.
Chemical conversion
Niloufar Davodi; Esmaeil Rasooly Garmaroody; Omid Ramezani; Sepideh Haamedi
Abstract
In this study, in order to control the inhibitory compounds in the bio-refinery, bagasse pith was pretreated under acidic hydrolysis with dilute sulfuric acid 8%, 90 minutes at 120 ° C. Then, by using de-depleting methods of overliming, activated carbon and combining of both, removal of deterrent ...
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In this study, in order to control the inhibitory compounds in the bio-refinery, bagasse pith was pretreated under acidic hydrolysis with dilute sulfuric acid 8%, 90 minutes at 120 ° C. Then, by using de-depleting methods of overliming, activated carbon and combining of both, removal of deterrent compounds from the above pretreatment hydrolyzates was performed. In the overliming, calcium hydroxide and sulfuric acid, in activated carbon method, activated carbon was used at three levels (0.5, 1.5 and 2.5%) and in the combined method of the combination of materials in the two previous methods became after acid treatments and each of the methods of insemination, the amount of recovered sugars and the values of the inhibitory compounds of furfural and hydroxymethylfurfural in the hydrolyzate were measured as two important indicators. The results showed that application of the above methods on hydrolyzate increased the yield of reduced sugars, so that the highest sugar yield (˃32%) was obtained after the independent method of overliming. In addition, active and combined carbon autonomous methods (overlimming and activated carbon) have an optimum activated carbon consumption of 2.5 and 1.5%, respectively. The qualitative study of the presence of inhibitory agents in hydrolyzates showed that furfural and hydroxymethylfurfural have maximum absorption at wavelengths of 276 and 282 nm. Also, an overliming with 2.5% activated carbon as the best method could eliminate up to 100% of inhibitory compounds. On the other hand, the autonomous method of overliming, with the removal of ˃90% of the inhibitory compounds, also has the highest sugar yield. Therefore, taking into account simultaneously the rate of sugar yield and the elimination of deterrent compounds, two independent alternatives of Overliming and Overliming with 2.5% active carbon could be proposed for the production of bioassays, such as bioethanol, xylitol, ... from the pith of bagasse.
