Shaq El-Thoaban industrial cluster, East Cairo the largest marble and granite industrial agglomeration in Egypt as well as the fourth world ranked marble and granite industrial zone poses the most ...imminent hazard to the surrounding environment and the neighboring residential communities due to the huge amounts of waste resulted during the processing of the marble and granite. The objective of the current study was to link Shaq El-Thoaban industrial area-as a marble (carbonate) waste source – to the cement industries in its neighborhood. Three cement factories are located within 2–10km far from Shaq El-Thoaban area, an advantage economically companies are appealing. Consequently, the current study investigated the characteristics of the marble powder waste generated during the processing at Shaq El-Thoaban area and its feasibility as an addition to the OPC produced at the near cement companies. Determining the physico–chemical and mechanical properties of the marble waste on the cement properties proved that 5wt.% could be, safely, added to the cement without adverse effects on the cement properties. Addition of such modest to the cement (or replacing part of the used gypsum in the cement manufacture) could be a real energy and financial saving concept, besides, saving part of the natural resources and alleviating the environmental impact imposed by the marble processing waste.
The present research was conducted to study the efficacy of low pressure plasma treatment in modification of parboiled rice flour. Parboiled rice samples were taken and plasma treated at varying ...power of 30 W, 40 W and 50 W for duration of 5, 10 and 15 min. After treatment, the parboiled rice was ground for examining physico–chemical and functional properties of the flour. From the analysis, it was found that plasma treatment could improve the flour hydration and gel hydration properties of the flour. Plasma treatment induced cross-linking of flour. On the contrary, the plasma treatment reduced the amylose content from 30.34 ± 0.13 to 27.89 ± 0.09%, which in turn caused a decline in the amylose to amylopectin ratio. This observed result could be due to depolymerization of starch, which is proved to happen during plasma treatment. Other changes that were observed after treatment are increase in gelatinization temperature. Plasma induced changes resulted, decline in endothermic enthalpies from 7.90 ± 0.21 to 7.47 ± 0.21 and changes in % crystallinity of flour from 28.25 ± 0.07 to 24.36 ± 0.48. Further, the phenolic content and antioxidant properties of treated flour samples were also influenced after treatment. It can be concluded that cold plasma treatment can be promising technology for improving functionality of flour.
•Plasma treatment improved the gel and flour hydration properties of parboiled rice flour.•Changes in crystalline structure of parboiled rice flour.•Decrease in endothermic enthalpy.•Modification of flour by plasma treatment.
Physicochemical and bio-functional properties of three starches including native starch (NS), the dual enzyme-treated starch (DES) and the cross-linked carboxymethyl starch (CCS) were investigated in ...the current study. The resistant starch (RS) contents ranged from 33.91 to 43.71%, which were decreased by modification. For the first time, the anti-constipation and hypolipidemic effect of yam starches are demonstrated. Three starches were characterized by scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and FT-IR spectroscopy. DES's crystalline structure collapsed and lost its granular shape during modification, indicating that DES had a high water binding capacity and high solubility. However, only minor changes of CCS's granular surface and crystallinity were observed. Furthermore, anti-constipation effect of the three yam starches was evaluated by intestine propulsion and defecation in constipated mice. There was more short chain fatty acids (SCFAs) produced in colon with DES and CCS, than that with native starches. Therefore, the modified starches were proved to be better for improving the small intestine propulsion function by generating more SCFAs. Hypolipidemic effect was also evaluated by monitoring the triglyceride (TG) and total cholesterol (TC) levels in mice. This study reports new bioactive starches, with potential applications in the pharmaceutical and food industries.
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•Two types of resistant starches were produced by dual enzymatic hydrolysis and cross-linked carboxymethylation.•The resistant starch content of native starch decreased by modification.•Two modified starches were more effective in increasing acetic acid and butyric acid concentration in the feces.•Two modified starches may be used to reduce constipation and hyperlipidemia.
This work is an overview of the literature in the area of microwave treatment of starch strongly related to changes in its physicochemical, functional and structural properties. The importance of ...good knowledge of the microwave parameters and starch dielectric properties is highlighted to avoid the improper microwave application on starch or starch‐based materials. Future perspectives of microwave processing of starch are suggested.
Biodegradable polymers have been widely used in tissue engineering for their good biocompatibility, controlled mechanical properties and processability. Among them, poly(glycerol sebacate) (PGS) is a ...promising biodegradable polymer that has been used in diverse tissue engineering applications such as skin, muscle, cornea, nerve, vessel, cartilage, and so on. However, one of the synthesis parameters, curing time on PGS properties is still a confusing problem waiting to be resolved. In this article, PGS was cured for 0, 24, 36, 48, 60, 72, 84, and 96 h at 130°C and their properties were characterized by a series of techniques. Differential scanning calorimetry results indicated that the melting point, crystallization temperature, melting enthalpy and crystallization enthalpy of PGS decreased with the increase of curing time. Curing time was positively correlated to the degree of crosslinking. Longer curing time not only enhanced Young's modulus of PGS but also reduced its hydrophilicity. The Young's modulus of PGS curing for 96 h was about 5 times higher than that of PGS curing for 36 h. This study suggests that the effect of curing time on PGS properties provides detailed reference for potential applications.
Lotus (Nelumbo nucifera G.) seeds are rich in nutrients and mainly used for food and medicinal applications. The seeds are an important food item in many countries and are generally considered a low ...glycemic index food. Starch is a major component of lotus seeds and may amount to over 50% of the dry weight. The quality of lotus seed products is mainly determined their starch properties, such as gelatinization and retrogradation. This review comprehensively summarizes recent developments in isolation, modifications, and applications of lotus seed starch (LS). This survey highlights different properties of native and modified LS in comparison with other starches. Native LS has been found with high amylose content (20–35%), high peak gelatinization temperatures (>70 °C), and pasting temperatures (>75 °C). The high amylose content has contributed to lower swelling power and fast retrogradation of LS. The modification of LS has been done using different methods, including thermal, microwave, high pressure, chemical, and enzymatic processing for functionality improvement. Native and modified LS have promising potential to be a valuable functional ingredient in different food and other applications. Finally, an outlook on the future possibilities for utilization of LS is provided.
Lotus (Nelumbo nucifera G.) seed is a good source of starch which contributes up to over 50% of seed dry weight. Interest is growing in its utilization owing to recent studies on the isolation, chemical composition, morphology, granular structure, physico‐chemical properties, different modifications practices.
Biochar has been of considerable importance for various environmental applications in recent years. It has exhibited substantial advantages like favourable structural and surface properties, easy ...process of preparation and widely available feedstocks. These set of exceptional properties make it an efficient, cost-effective and environment friendly source for diversified elimination of pollutants. The heterogeneity of physico-chemical properties offers a possibility for biochar to optimize its efficacy for targeted applications. This review aims to highlight the critical role that biochar plays in various environmental applications, be it in soil, water or air. In particular the article offers a comprehensive review of the recent research findings and updates related to the diversified role of biochar. Also, the interaction of pollutants with biochar functional groups and the impact of variation of parameters on biochar attribute relevant to specific pollutant removal, modifications, mechanisms involved and competence for such removal has been discussed. Different technologies for production of biochar have also been summarized with an emphasis on post treatment of biochar, such as modification and doping. In addition to this, the underlying gaps in the studies carried out so far and recommendations for future research areas in biochar have also been deliberated.
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•Recent multidimensional diversified roles of biochar are reviewed.•Biochar is likely to replace activated carbon in near future.•Biochar has distinctive properties for eliminating soil, water and air contaminants.•Sorption depends on biochar's surface properties, micro porosity and hydrophobicity.
Soil acidification is caused by a number of factors including acidic precipitation and the deposition from the atmosphere of acidifying gases or particles, such as sulphur dioxide, ammonia and nitric ...acid. The most important causes of soil acidification on agricultural land, however, are the application of ammonium‐based fertilizers and urea, elemental S fertilizer and the growth of legumes. Acidification causes the loss of base cations, an increase in aluminium saturation and a decline in crop yields; severe acidification can cause nonreversible clay mineral dissolution and a reduction in cation exchange capacity, accompanied by structural deterioration. Soil acidity is ameliorated by applying lime or other acid‐neutralizing materials. ‘Liming’ also reduces N2O emissions, but this is more than offset by CO2 emissions from the lime as it neutralizes acidity. Because crop plants vary in their tolerance to acidity and plant nutrients have different optimal pH ranges, target soil pH values in the UK are set at 6.5 (5.8 in peaty soils) for cropped land and 6.0 (5.3 in peaty soils) for grassland. Agricultural lime products can be sold as ‘EC Fertiliser Liming Materials’ but, although vital for soil quality and agricultural production, liming tends to be strongly influenced by the economics of farming. Consequently, much less lime is being applied in the UK than required, and many arable and grassland soils are below optimum pH.
Since its first isolation in 1934, hyaluronic acid (HA) has been studied across a variety of research areas. This unbranched glycosaminoglycan consisting of repeating disaccharide units of
...-acetyl-d-glucosamine and d-glucuronic acid is almost ubiquitous in humans and in other vertebrates. HA is involved in many key processes, including cell signaling, wound reparation, tissue regeneration, morphogenesis, matrix organization and pathobiology, and has unique physico-chemical properties, such as biocompatibility, biodegradability, mucoadhesivity, hygroscopicity and viscoelasticity. For these reasons, exogenous HA has been investigated as a drug delivery system and treatment in cancer, ophthalmology, arthrology, pneumology, rhinology, urology, aesthetic medicine and cosmetics. To improve and customize its properties and applications, HA can be subjected to chemical modifications: conjugation and crosslinking. The present review gives an overview regarding HA, describing its history, physico-chemical, structural and hydrodynamic properties and biology (occurrence, biosynthesis (by hyaluronan synthases), degradation (by hyaluronidases and oxidative stress), roles, mechanisms of action and receptors). Furthermore, both conventional and recently emerging methods developed for the industrial production of HA and its chemical derivatization are presented. Finally, the medical, pharmaceutical and cosmetic applications of HA and its derivatives are reviewed, reporting examples of HA-based products that currently are on the market or are undergoing further investigations.
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