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Background. Lactobacillus acidophilus has become increasingly popular because of their beneficial effects on health of their host, and are called proboscis. In order to exert beneficial effects for probiotics, they must be able to tolerate the acidic conditions of the stomach environment and the bile in the small intestine. Micro- encapsulated form has received reasonable attention, since it can protect probiotic organisms against an unfavourable environment, and to allow their release in a viable and metabolically active state in the intestine. The aim of this study was to investigate some factores, such as chitosan solution pH and concentration, xanthan concentration, cell suspension-xanthan ratio, mixed bacteria glue liquid-chitosan ratio, which impacted the process of microencapsulation of L. acidophilus. Material and methods. In this study, L. acidophilus was immobilized with xanthanthitosan gel using extrusion method. The viable counts and encapsulation yield of L. acidophilus encapsulated in different chitosan solution pH (4.5, 5, 5.5 and 6), in different chitosan concentration (0.5%, 0.7%, 0.9% and 1.1%), in different xanthan concentration (0.5%, 0.7%, 0.9% and 1.1%), in different cell suspension-xanthan ratios (1:5, 1:10, 1:15 and 1:20), in different mixed bacteria glue liquid-chitosan ratios (1:3,1:4,1:5 and 1:6), have been investigated by single factor experiment method. Results. The optimum conditions of microencapsulated L. acidophilus have been observed. The optimum chitosan solution pH for L. acidophilus was 5.5; the optimum chitosan concentration was 0.9%; the optimum xanthan concentration was 0.7%; the optimum cell suspension-xanthan ratio was 1:10; the optimum mixed bacteria glue liquid-chitosan ratio was 1:3. Conclusions. These results will be helpful to further optimize the process of L. acidophilus microencapsulation, and provide reference for obtaining higher viable counts and entrapped yield of L. acidophilus microcapsules.
The present investigation was carried out to evaluate the potential of chitosan alone and in combination with various agricultural wastes for the management of rootknot nematode, Meloidogyne incognita on eggplant cv. ‘BR-112’ under greenhouse conditions. The results showed that chitosan as a single or joint treatment with agricultural wastes significantly (p ≤ 0.05) reduced root-knot indices, and the nematode population in soil. As a result, of this, the growth and growth yielding attributes of eggplant were remarkably augmented. Chitosan as an elicitor induced plant mediated systemic resistance against M. incognita in eggplant. The results of the study demonstrated that maximum reduction in eggmass/root, eggs/eggmasses, nematode population and root-knot indices, was acquired by the treatments: chitosan + onion and chitosan + mentha. It was followed by chitosan + Brassica, chitosan + urad and chitosan + coconut whereas, chitosan combined with corn cob waste was found to be the least effective when compared to the control. The application of chitosan alone was effective but not very satisfactory. Compared to the control applications of all the treatments significantly increased plant growth in terms of length, fresh and dry weights, pollen fertility, yield and biochemical parameters such as chlorophyll, carotenoid content and antioxidant enzymes. This may have been due to the eliciting activity of chitosan, causing systemic resistance in the plant and the release of various toxic chemical compounds during decomposition which have lethal effects against the second stage juveniles of M. incognita and nematode multiplication.
The study involved mice of an inbred CFW line from the author’s own culture conducted according to the street light method (Lane Petter and Pearson 1971). All the animals, aged about 3 months and weighing 20 g each, were infected per os with 200 T. spiralis larvae per mouse. A total of 76 mice, divided into two groups, were used. Group I constituted the control and consisted of T. spiralis-infected mice, while Group II consisted of chitosan (chitosan adipinate)-treated mice receiving a dose of 0.4 mg per mouse, administered intra-peritoneally for 20 days (6 days prior to infection until day 13 post-infection). Four mice of each group were sacrificed by decapitation on invasion day 7, 14, 21, 28, 35, 42, and 60. Sections of the jejunum and mandibular muscle were used to prepare populations of cells involved in the inflammatory infiltration. The populations selected were the T (CD4+ and CD8+) lymphocytes and macrophages. The first were identified with immunofluorescence, using labelled monoclonal antibodies, while identification of the latter proceeded immunoenzymatically, with non-labelled monoclonal antibodies. In addition, the infected animals in each group were examined for the presence of parasites: on day 7, 10, 14, and 21 post-infection, the intestinal parasites were counted, while, the muscle-dwelling larvae being enumerated on day 60 post-infection. In this study, the macrophage count in the jejunum mucosa basement membrane of the chitosan-treated mice increased until day 21 post-infection and remained, until the observations were terminated, at a level higher than that in the control. On the other hand, the transversely striated muscles revealed, in addition to T CD4+ and T CD8+ lymphocytes, a stronger macrophage mobilisation throughout the period of observations. The chitosan-treated mouse jejunum were also a site of a faster removal (“expulsion”) of adult parasites than in the control, the muscle larval count in those mice being clearly lower than in the control.
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Removal of chromium by biosorption method (chitosan)

63%
Discharge of metal containing effluents into water has been a cause of major concern. Traditional treatment methods are proving to be ineffective and expensive. Chitosan was studied as a potential biosorbent due to its positive charge and relatively low cost. The study involves evaluating the metal binding performance of chitosan in a Polymer Enhanced Diafiltration (PEDF) system which uses an ultra filtration membrane to retain the chitosan which, in turn, binds the metal, thereby preventing passage into the permeate stream. Conditions for binding such as pH, concentration of polymer and chromium were studied. Optimal performance was obtained when the system was operated at pH values lower than the pKa of chitosan i.e. 6.3. Using 6 g/L chitosan at pH 4.0, chromium concentration was reduced to less than 1mg/L from a feed concentration of 20 mg/L. Equilibrium dialysis experiments were done to study the kinetics of binding and the uptake of metal per gram of polymer. Rheological measurements demonstrated that in the presence of 1-100 mM chromate, chitosan was found to be slightly shear thickening at low concentrations such as 4 g/L and 6 g/L whereas it was slightly shear thinning at higher concentrations like 12 g/L and 20 g/L This suggests that neutralization of chromium anions is due to the interaction of multiple chitosan molecules. This result is consistent with the relatively stiff nature of the polysaccharide. Overall, this study suggests that some modification of the native polymer would be required to improve uptake and make it an industrially workable process.
Изложена актуальность разработки технологии и технического обеспечения производства микобиопрепаратов на основании элиситоров полисахаридной природы – хитина и глюканов. Рассмотрены современные представления о ключевых механизмах индукции устойчивости растений. Представлена технологическая схема модельной биотехнологии получения полисахаридов из клеточной стенки гриба трутовика настоящего.
The subject of the studies was the soil with introduced solutions containing 0.1 % chitosan. These materials were obtained from the Institute of Chemical Fibres in Łódź (in the form of a microcrystalline gel) and also from the Department of Food Biochemistry and Chemistry of the University of Agriculture in Lublin (in a liquid form, Le. dissolved in acetic acid). In order to set an experiment in a growth chamber, grey brown podzolic soil formed from loesses and taken from a mechanically treated belt of black fallow was used. The soil (1000 g) was watered every 8 days with 100 ml of examined chitosan solutions per pot. Control soil was watered with sterile distilled water. Seven days after each watering, soil samples were taken for microbiological analysis. Then 25 runner bean seeds were sown into each pot. After six weeks of plants' growth the experiment was finished and the number of plants was counted, their healthiness deterrmined and soil microbiological analysis was performed. Regardless of chitosan form introduced to the soil it stimulated the growth of bacteria and fungi, since in these experimentall combinations was found a significantly higher number of microorganisms as compared with the control. A particular high increase in the number of microorganism colonies was observed with simultaneous growth of plants and the application of chitosan. A considerable increase of fungi colonies from the Trichoderma genu s was found in the soil treated with chitosan in the form of both a microcrystalline gel and a liquid. The species of this genus are considered to be antagonists; it affects pathogenic fungi through competition, antibiosis and over-parasitism. An increase in colonies of saprophytic microorganisms, including antagonistic ones of Bacillus spp. and Pseudomonas spp. was observed in the soi l treated with chitosan . On the other hand, in the soil after the growth of bean and treated watered with chitosan only few colonies of Fusarium oxysporum f.sp. phaseoli - bean pathogen were found. The healthiness of plants grown in soil treated with chitosan was significantly better as compared to the control. The populations of antagonistic microorganisms formed in the soil in these treatments probably limited the growth of pathogenic fungus.
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