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Artificial cell microcapsules containing live bacterial cells and activated charcoal for managing renal failure creatinine: preparation and in-vitro analysis

Abstract

Activated charcoal was microencapsulated with Lactobacillus acidophilus 314 previously adapted for urea uptake. The creatinine removal capacity of this combination microcapsule was evaluated in-vitro in media simulating the small intestine. Results show that microcapsules containing both activated charcoal and L. acidophilus 314 demonstrated potential for decreasing creatinine. Interestingly, when co-encapsulating both activated charcoal and L. acidophilus 314 a smaller decrease in creatinine was observed than when encapsulating them separately. However, co-encapsulated microcapsules were more stable in various parts of the gastrointestinal system and survived longer in storage. These results suggest the feasibility of using microcapsules containing activated charcoal and probiotic bacteria as oral adjuvants for creatinine removal and provides a theoretical model for the use of these microcapsules to remove any unwanted metabolite.

Open access
A comparison of machine learning algorithms for the prediction of Hepatitis C NS3 protease cleavage sites

Abstract

Hepatitis is a global disease that is on the rise and is currently the cause of more deaths than the human immunodeficiency virus each year. As a result, there is an increasing need for antivirals. Previously, effective antivirals have been found in the form of substrate-mimetic antiviral protease inhibitors. The application of machine learning has been used to predict cleavage patterns of viral proteases to provide information for future drug design. This study has successfully applied and compared several machine learning algorithms to hepatitis C viral NS3 serine protease cleavage data. Results have found that differences in sequence-extraction methods can outweigh differences in algorithm choice. Models produced from pseudo-coded datasets all performed with high accuracy and outperformed models created with orthogonal-coded datasets. However, no single pseudo-model performed significantly better than any other. Evaluation of performance measures also show that the correct choice of model scoring system is essential for unbiased model assessment.

Open access
Differences in organic matter quality, chemical and microbiological characteristics of two Phaeozems under natural and anthropic influence

Abstract

The soil degraded and changed by the anthropic activity must be monitored and the awareness of the intrinsic processes will allow a pertinent analysis of the effects of the application of the new technologies on the management and the sustainability of the soil.

Two natural and anthropic Phaeozems were analyzed from the point of view of chemical, microbiological characteristics, quality and composition of organic compounds.

Total values of microbial biomass and bacterial and fungal counts were generally twice higher in Calcaric Phaeozems than in Verti-Stagnic Phaeozems.

The content of humic precursors in Calcaric Phaeozems was quantitatively higher than that determined in Verti-stagnic Phaeozems, with a total content of phenols of 14.6mgGAExg−1d.m., polysaccharides and proteins of 97mgxg−1, respectivelly 16.6mgxl−1.

The ascending chromatograms showed specific distribution and higher density of the organic compounds in the CAFT sub-fraction of the Verti-stagnic Phaeozems. Pfeiffer specific chromatograms revealed an enzyme activity much higher than average at the Verti-stagnic Phaeozems, with a well-characterized functional diversity. The nutritional reserve appeared increased but poorly diversified in the Calcaric Phaeozems. Humification processes are intense, colloidal substances are present, the mineral component is very well integrated in the organic material at the Verti-stagnic Phaeozems and complex protein content is well revealed especially in the Calcaric Phaeozems.

Capillary dynamolysis reflected a characteristic pattern of Phaeozems soils, with particularities for each soil type, represented by colors, contours and particular forms of the specific structures developed.

Both soils presented good conditions for sustaining vegetation either natural or cultivated but results indicated that anthropic intervention determined a more dynamic mineralization of organic matter. Further monitoring of soil organic matter dynamics is needed and adjusting management practices for conservation of biodiversity and global ecosystem protection against the effect of anthropic intervention.

Open access
Photosynthetic light reactions in Oryza sativa L. under Cd stress: Influence of iron, calcium, and zinc supplements

Abstract

Some mineral nutrients may help to alleviate cadmium stress in plants. Therefore, influence of Fe, Ca, and Zn supplements on photosynthesis light reactions under Cd stress studied in two Indian rice cultivars namely, MO-16 and MTU-7029 respectively. Exogenous application of both Fe and Ca ions helped to uphold quantum efficiency and linear electron transport during Cd stress. Also, recovery of biomass noticed during Cd treatment with Fe and Ca supplements. It was found that accumulation of carotenoids as well as non photochemical quenching enhances with Fe, Ca, and Zn supplements. Chlorophyll a/b ratio increased with Cd accumulation as a strategy to increase light harvest. Lipid peroxidation level was ascertained the highest during Cd plus Zn treatments. Above results point that both Fe and Ca ions supplements help to alleviate Cd stress on photosynthesis light reactions of rice plants.

Open access
Polymerization degree-dependent changes in the effects of in vitro chitosan treatments on photosynthetic pigment, protein, and dry matter contents of Ipomoea purpurea

Abstract

Morning Glory (Ipomoea purpurea (L.) Roth.) is a climbing plant known for its ornamental properties and ease of cultivation in temperate climates. Quality and colour of flowers and leaves, especially in the production of ornamentals, are important parameters both for producers and for customers. This study aimed to investigate the changes in photosynthetic pigment, protein and dry matter content of in vitro-propagated I. purpurea following chitosan treatment with different polymerization degrees (DP) and to determine the indirect effect of this biopolymer on leaves of the plant. Nodal explants of I. purpurea were cultured in medium supplemented with 5, 10 and 20 mg L−1 concentrations of a chitosan oligomers mixture with a variable degree of polymerization (DP) ranging from 2 to 15 or chitosan polymer with DP of 70. It was found that both oligomeric and polymeric chitosan treatments increased chlorophyll-a contents in the leaves when compared to the chitosan-naïve control group. Polymeric chitosan stimulated chlorophyll-b and carotenoid synthesis more effectively than the oligomer mixture. Also, 10 mg L−1 polymeric chitosan better triggered total protein production and plant dry matter content in I. purpurea. The results of this study showed that, due to their stimulatory effects on photosynthetic pigment, protein and plant dry matter production, chitosan oligomers at low concentration and polymers at moderate concentration might be considered as safe and natural biostimulants for ornamental plants which could affect the plant’s attractiveness and commercial success.

Open access
Biocomposites based on collagen and keratin with properties for agriculture and industrie applications

Abstract

In the present research biocomposites based on extracts of collagen and keratin recovered from the leather industry by-products were made and the specific properties for applications in agriculture and industry were studied. To this aim, collagen and keratin have been extracted from bovine leather and sheep wool by-products and have been added and crosslinked with recognized compounds for reduced environmental impact (glycerol, vegetable tanning extract, essential oils with fungicidal properties and insecticides). The biocomposite properties were evaluated on the basis of complex analytical investigations on chemical structure, texture, contact angle, mechanical resistance, water vapor permeability and water absorption, biodegradation, germination and plant biomass growth. The biocomposites have demonstrated pelliculogenic properties and nitrogen controlled release to stimulate germination and nutrition of rape seedlings, which promotes them for agricultural applications, but also other surface properties have been identified, for industrial applications, for example in leather finishing for special destinations. Addition of odorous principles with controlled release recommends this type of biocomposites for environmentally friendly products, maintenance of cleaning, etc.

Open access
Corrosion inhibition of iron surfaces with phosphatidic acid

Abstract

Preventing the corrosion of iron in inaccessible structures requires a coating method that reaches all surface areas and creates a uniform protective layer. An ages old practice to protect iron artefacts is to coat them with animal fat, that is, a mixture of lipids. This “method” is accidentally ingenious: some natural phospholipids found in animal fat have the potential to form a tightly packed self-assembled monolayer on metal oxide surfaces, similar to the surfactant monolayers that have attracted increasing attention lately. Thus, the most primitive corrosion prevention method may point at a way to coat complex iron structures in an industrial environment. Here the ability of phosphatidic acid, a natural lipid, to coat and protect iron surfaces was examined. Iron coated quartz crystal microbalance (QCM) sensors were used for the experiments, to monitor the deposition of the lipid as well as the acidic corrosion (dissolution) of iron in situ, in real time. The sensors were coated by self-assembled monolayers of di-myristoyl phosphatidic acid using the liposome deposition method. In this process, 50-100 nm vesicles formed by the lipid are delivered in an aqueous solution and spontaneously coat the iron surfaces upon contact. QCM and ellipsometry measurements confirmed that continuous bilayer and monolayer surface coatings can be achieved by this method. QCM measurements also confirmed that the layers were corrosion resistant in 0.01M acetic acid solution that would dissolve the thin iron layer in minutes in the absence of the protective coating. XPS results suggested a chemisorption-based mechanism of phosphatidic acid attachment to the iron surface. Hence, liposome deposition of phosphatidic acid offers a suitable solution to coat iron surfaces in inaccessible structures in situ.

Open access
Defense manifestations of enzymatic and non-enzymatic antioxidants in Ricinus communis L. exposed to lead in hydroponics

Abstract

Lead (Pb) is a major inorganic pollutant with no biological significance and has been a global concern. Phytotoxicity of lead induces toxic effects by generating reactive oxygen species (ROS), which inhibits most of the cellular processes in plants. Hydro-ponic experiments were performed with Ricinus communis to investigate the toxicity and antioxidant responses by exposing to different concentrations of lead (0, 200 and 400 µM) for 10 days. Pb stress caused a significant increase in electrolyte leakage, non-enzymatic antioxidants (phenols and flavonoids) and a decrease in the elemental profile of the plant. Histochemical visualization clearly indicates the significant increase of H2O2 production in dose-dependent manner under Pb stress. Likewise, an increase in catalase, guaiacol peroxidase and superoxide dismutase activity was also evident. Ascorbate peroxidase and MDAR, on the other hand, responded biphasically to Pb treatments showing a decrease in concentration. The decline in redox ratio GSH/GSSG was imposed by the indirect oxidative stress of Pb. Hence these findings showed the ameliorative potential of R. communis to sustain Pb toxicity under oxidative stress.

Open access
Evolution of phytochemical and antioxidant activity of Tunisian carob (Ceratonia siliqua L.) pods during maturation

Abstract

The Ceratonia siliqua fruits contain several substances known to have high adaptability to environmental conditions. The aim of this paper is to evaluate the changes in physicochemical properties of different Tunisian provenances of carob pulps harvested at three ripening stages. Furthermore, six provenances were investigated during the ripening process in terms of their moisture, ash, minerals, bioactive compounds, antiradical activity and sugar profile. The results demonstrated that all examined parameters are highly influenced by geographic origin. Concerning ripening impact, our data showed that water and ash content significantly decreased during the development of six provenances, as well as the bioactive and mineral contents. Thus, the total polyphenols (TP), total flavonoids (TF) and condensed tannins (CT) contents exhibited the highest levels in the unripe fruits. The antiradical activity trend was positively correlated to the behavior of the bioactive compounds content. Moreover, the sucrose, glucose and fructose were the main sugar qualified and quantified in carob pods at different ripening stages. At the maturity stage, the monosaccharide contents (glucose and fructose) were slightly reduced, while, the sucrose was rapidly accumulated. In conclusion, the ripening process diversely affected the nutritional composition and generally extended the exploitation of carob fruits. The study could provide valuable information about the suitability of carob pods at different maturity stages as potential biomaterials for nutraceutical applications.

Open access
Optimization of in vitro asymbiotic seed germination protocol for Serapias vomeracea

Abstract

Serapias vomeracea is an economically important orchid species which is over-collected from nature, because of its glucomannan-rich tubers. Thus, optimization of in vitro culture methodology in this species is required to meet industrial needs and to secure its populations in nature. This study aimed to optimize the surface sterilization protocol for S. vomeracea seeds and to select the optimal seed germination medium by comparing the commonly used media in in vitro orchid culture. During seed surface sterilization, ethyl alcohol (EtOH) pre-treatment prior to sodium hypochlorite (NaOCl) treatment increased the disinfection success and viable seed yield when examined using the triphenyl tetrazolium chloride (TTC) seed viability test. Also, low-g force centrifugation as an additional step in the surface sterilization method separated the seeds without embryo from the viable seeds and thereby decreased potential counting errors after incubation. Comparison of media showed that solid Knudson C (KN) medium induced the highest number of germinated seeds. However, seed germination success of Lindemann (LN) and Vacin & Went (VW) media was found to be higher when the media was used in liquid form. Half-strength liquid VW was the only medium that induced higher germination success than the other full-strength media. The highest number of ungerminated seeds was found when using KN medium whereas liquid VW medium gave the lowest number. In general, protocorm formation was triggered when the media were used in liquid form. However, rhizoid elongation was suppressed in liquid media. These findings suggest that this optimized seed surface sterilization method offers a simple and effective alternative to classical methods. Additionally, solid KN medium may be considered as a cost-effective and reliable alternative to other commonly-used complex media in S. vomeracea cultures.

Open access