Mitochondrial DNA lineages of Italian Giara and Sarcidano horses

Giara and Sarcidano are 2 of the 15 extant native Italian horse breeds with limited dispersal capability that originated from a larger number of individuals. The 2 breeds live in two distinct isolated locations on the island of Sardinia. To determine the genetic structure and evolutionary history of these 2 Sardinian breeds, the first hypervariable segment of the mitochondrial DNA (mtDNA) was sequenced and analyzed in 40 Giara and Sarcidano horses and compared with publicly available mtDNA data from 43 Old World breeds. Four different analyses, including genetic distance, analysis of molecular variance, haplotype sharing, and clustering methods, were used to study the genetic relationships between the Sardinian and other horse breeds. The analyses yielded similar results, and the FST values indicated that a high percentage of the total genetic variation was explained by between-breed differences. Consistent with their distinct phenotypes and geographic isolation, the two Sardinian breeds were shown to consist of 2 distinct gene pools that had no gene flow between them. Giara horses were clearly separated from the other breeds examined and showed traces of ancient separation from horses of other breeds that share the same mitochondrial lineage. On the other hand, the data from the Sarcidano horses fit well with variation among breeds from the Iberian Peninsula and North-West Europe: genetic relationships among Sarcidano and the other breeds are consistent with the documented history of this breed

Factors influencing MOW deinking : laboratory scale studies

The deinking of MOW is examined at laboratorial scale. The effect of deinking aids, pre-washing and mixing are studied. The operating conditions during pulp treatment affect the pulp and paper properties, interfering with the mechanism of ink removal and modifying the ink particle characteristics. Pre-washing the pulp facilitates the deinking process. Cellulolytic enzymes and deinking chemicals are comparable in terms of ink removal ability.Portucel Vian

Enzymatic versus chemical deinking of non-impact ink printed paper

Enzymatic versus chemical deinking is examined for MOW and photocopy prints. Several enzymatic preparations and two fibre/ink particle separation methods are tested. Deinking was monitored by image analysis and standard pulp and paper characterisation procedures. The effectiveness of the fibre/ink particle separation method depends on the ink particle’s size: for smaller particles a washing step is recommended whereas for larger particles, the use of flotation is necessary. The enzymatic treatment is a competitive alternative for MOW and photocopy paper deinking. However, the process requires the selection of an adequate enzymatic preparation for each paper grade

Refining and enzymatic treatment of secondary fibres for paperboard production : Cyberflex measurements of fibre flexibility

Recycling is generally affected by secondary fibre quality. High temperature and pressure during the drying stage causes irreversible changes in fibre morphology, which is the mainly responsible for the considerable reduction in the swelling and bonding ability (strength and number of bonds) [1, 2, 3]. Additionally, the reduced dewatering ability of these pulps is a major problem during paper manufacture as they decrease the speed on the paper machine and worsen sheet formation [4]. Secondary fibre upgrade is difficult and sometimes unpredictable, as the samples to be treated vary along with their history. Traditional upgrade methodologies have been used to improve secondary fibre properties, but the results are most of the times insufficient [1, 5]. Different reports suggest that treating pulps with enzymes and refining could overcome these problems [4, 6, 7, 8, 9]. More recently, Cellulose-Binding Domains (CBD’s) usage has been shown as an interesting tool to modify recycled fibres properties

Modification of secondary pulp fibre fractions by enzymatic treatment

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Enzymatic modification of paper fibres

The enzymatic mode of action in paper fibre upgrading is still uncertain. In an attempt to clarify how enzymes modify pulp and paper properties, several parameters were analysed in the present work: (i) thermal analysis of the water–solid surface interactions; (ii) fibre cake permeability; (iii) particle size analysis. The results obtained suggest that enzymes modify the interfacial properties of fibres, increasing the water affinity, which in turn change the technical properties of pulp and paper, such as drainability and strength. The modification of paper and pulps following a treatment with cellulosebinding domains further supports this hypothesis

Effects of enzymatic treatment and refining on the properties of recycled pulp

The effect of refining and enzymatic treatment on secondary fibre properties is shown. The following treatment sequences were studied: (i) refining; (ii) refining + enzymatic treatment; (iii) enzymatic treatment + refining; (iv) enzymatic treatment. The effectiveness of the methods was evaluated by measuring physical and mechanical properties of pulp and paper (drainage rate, burst, tensile and tear indexes). The obtained data revealed that combined refining and enzymatic treatment can be considered as a valuable methodology to upgrade recycled pulps. The first is responsible for increasing burst and tensile resistance. The second, if developed under controlled conditions, alloes better drainage, with only slight variation on paper mechanical properties