Rehana Iqbal

Pectins functionalized biomaterials; a new viable approach for biomedical applications: A review

Pectins are natural complex heteropolysaccharides, composed of (1, 4)-linked α-d-galacturonic acid residues and variety of neutral sugars such as rhamnose, galactose and arabinose. It is second most abundant component of the cell wall of all land plants. It has wide applications in various fields due to its use as gelling, emulsifying or stabilizing agent and as well as its non-toxic, biocompatible and biodegradable nature. Considering these versatile properties this review sheds a light on the synthesis, modification, characterization and applications of pectin based polymers. Most of them are used in industries, pharmaceutics, nutraceutics, drug delivery, tissue engineering, food packaging and cosmetics. Properties of pectin can be improved and modified by forming derivatives, blends and composites.

Blends and composites of exopolysaccharides; properties and applications: A review

Exopolysaccharides are synthesized by bacteria and secreted into the external environment and they may be homopolymeric or heteropolymeric in configuration. They are believed to protect bacterial cells from heavy metals, desiccation or other environmental effect. EPS exhibit antitumor, anti-HIV, emulsion stabilization capacity, shear-thinning activity, suspension ability, high viscosities, excellent biocompatibility, high biodegradability and immunomodulatory properties. They are widely used in herbicides, functional food, nutraceuticals, cosmeceuticals, pharmaceuticals, insecticides, immunomodulation and anticoagulants. This review shed light on the properties and versatile applications of xanthan, curdlan, hyaluronic acid and dextran blends and composites with natural and synthetic polymers.

Effect of cadmium chloride and ascorbic acid exposure on the vital organs of freshwater Cyprinid, Labeo rohita

The present study was carried out to evaluate the impact of sub lethal concentrations of heavy metal, cadmium chloride (CdCl 2 .H 2 O), ascorbic acid (vitamin C) and their combination on Labeo rohita . The effect was investigated on the basis of histopathological examinations of control and experimental groups exposed to heavy metal. The acute semi statistical toxicity test for L. rohita revealed 96 h LC 50 value 22.92 mg L -1 for cadmium chloride (CdCl 2 .H 2 O). 215 fingerlings of L. rohita were exposed to three different experimental conditions for 96 h: 11.46 mg L -1 CdCl 2 .H 2 O, or 450 mg Kg -1 ascorbic acid or combination of both these doses. No alterations were observed in gill sections upon comparison between treated and untreated groups. Congestion in sinusoids, fatty change, an increase in Kupffer cells and intrahepatic lymphocytes was observed in CdCl 2 .H 2 O treated group. In kidney sections of heavy metal treated group, degeneration of the glomerular tissue, occlusion in tubular lumen and necrosis were observed. Similar changes but in less severe form, as described above, were observed in the fish exposed to combination of CdCl 2 .H 2 O and ascorbic indicating that ascorbic acid do detoxify the effect of heavy metal to some extant. Our results indicate that cadmium chloride (CdCl 2 .H 2 O), if present in fresh water bodies, may act as strong toxic agent for L. rohita . Keywords: Labeo rohita , cadmium chloride (CdCl 2 .H 2 O), ascorbic acid, histopathology

Investigating the bioavailability of graphene quantum dots in lung tissues via Fourier transform infrared spectroscopy

Biomolecular fractions affect the fate and behaviour of quantum dots (QDs) in living systems but how the interactions between biomolecules and QDs affect the bioavailability of QDs is a major knowledge gap in risk assessment analysis. The transport of QDs after release into a living organism is a complex process. The majority accumulate in the lungs where they can directly affect the inhalation process and lung architecture. Here, we investigate the bioavailability of graphene quantum dots (GQDs) to the lungs of rats by measuring the alterations in macromolecular fractions via Fourier transform infrared spectroscopy (FTIR). GQDs were intravenously injected into the rats in a dose-dependent manner (low (5 mg kg−1) and high (15 mg kg−1) doses of GQDs per body weight of rat) for 7 days. The lung tissues were isolated, processed and haematoxylin–eosin stained for histological analysis to identify cell death. Key biochemical differences were identified by spectral signatures: pronounced changes in cholesterol were found in two cases of low and high doses; a change in phosphorylation profile of substrate proteins in the tissues was observed in low dose at 24 h. This is the first time biomolecules have been measured in biological tissue using FTIR to investigate the biocompatibility of foreign material. We found that highly accurate toxicological changes can be investigated with FTIR measurements of tissue sections. As a result, FTIR could form the basis of a non-invasive pre-diagnostic tool for predicting the toxicity of GQDs.

Effect of various nutrient combinations on growth and body composition of rohu (Labeo rohita )

A total of 80 Labeo rohita fingerlings (mean body weight, 14.7 ± 0.08 g and length, 11.0 ± 0.16 cm) were randomly distributed into four treatments with 20 replicates each, for 60 days, to determine the effect of different feed compositions on the growth and body composition of L. rohita . Four isoenergetic (17.05 ± 0.24 kJ g -1 ) experimental diet viz., control (C), protein rich (PR), fat rich (FR) and carbohydrate rich (CR) were formulated. The proximate composition protein/fat/carbohydrate (P/F/C) of formulated feed were C: P35/F8/C2, PR: P40/F8/C2, FR: P35/F10/C2 and CR: P35/F8/C5. The daily ration size was 5% of fish body weight. The result reveals a highly significant (P≤0.001) difference in specific growth rate (SGR), weight gain (WG) and protein efficiency (PE) among four feeding groups, while differences were significant for feed conversion ratio (FCR). FR showed maximum growth together with high body fat, CR showed low body fat and high proteins. Results indicate that increasing fat up to 9% in diet showed better growth as compared to increasing dietary protein and carbohydrates Key words : Labeo rohita, diet composition, specific growth rate, protein efficiency, body composition.

Ameliorative effects of Moringa oleifera on copper nanoparticle induced toxicity in Cyprinus carpio assessed by histology and oxidative stress markers

Nanoparticles (NPs) enter the environment mainly through waste water effluents, accidental spillage, and industrial runoffs. This is worrying because NPs can enter the human body owing to their large aspect-to-size ratio and reactive surfaces that facilitate their penetration through biological barriers and thus can induce oxidative stress in host cells. Therefore, there is a growing concern about the toxicity of NPs, which needs to be addressed. Thus, this study investigated the ameliorative effects of Moringa oleifera seed extract (MOSE) in Cyprinus carpio exposed to copper nanoparticles (Cu-NPs). For the in vivo assessment of the shielding effects of MOSE, 240 samples of C. carpio (40-45 g) were randomly allocated to 24 experimental tanks (10 fish/tank of 40 L) 24 h prior to the start of this experiment. The experimental fish were faced with the water-born exposure of a pre-determined dose of 1.5 mg Cu-NPs/l along with pre- and post-treatment with different doses (100 or 200 or 300 mg l-1) of MOSE for 28 days. The MOSE showed significant ameliorative effect on the antioxidant defense, in response to the elevated levels of Cu-NP-induced oxidative stress. It also played a protective role as indicated by the suppression of the histological alterations in the gills and liver of fish exposed to the Cu-NPs. It was concluded that the Cu-NP-induced toxicity in C. carpio was ameliorated by the use of MOSE in this study. Moreover, the post-Cu-NP treatment stage showed more protective effects of MOSE than the pre-Cu-NP treatment phase. Further studies are suggested to determine the optimum dose and delivery method of MOSE for similar or different NP exposed fish.

Future Prospects of Algae-Based Materials

Environmental concerns and limited supply of fossil fuels have accelerated the research for the biofuels and biomaterials. Biomaterials not only resolve the issues related with the consumption of conventional fossil fuel–based polymeric materials but also have certain properties for new and wider range of applications. Algae-based polymers, composite, and blends present an important class of biomaterials with a wide range of application in numerous fields. However, there are certain challenges in commercialization of these biomaterials. This chapter discusses the future prospects, challenges in wider applications of algae-based materials, along with their potential solutions.

Origin of Algae and Their Plastids

Abstract Algae are of central importance in marine and freshwater ecosystems; however, their origin has remained an enigma. Recent molecular sequence analyses show that algae are of polyphyletic origins, and that their evolution is best explained by tracing the endosymbiotic events, which resulted in the origins of their plastids. Plastid is a major double-membrane cytoplasmic semiautonomous organelles, it synthesize or store various types of organic compounds. Plastids are derived from endosymbiotic event through a complex mix of movement, loss and replacement, non-photosynthetic plastids are being found in many non-photosynthetic lineages. In other cases, photosynthetic lineages have evolved from ancestors with a plastid of different origin, so an ancestral plastid has been replaced with a new one. On the basis of origin of algae and their plastids, the four distinct groups of algae include prokaryotes—the cyanobacteria; chloroplast-containing eukaryotic algae with one membrane of chloroplast endoplasmic reticulum (ER); chloroplast-containing eukaryotic algae that are surrounded by two membranes of chloroplast ER; and chloroplast-containing eukaryotic algae that are surrounded by two membranes of the chloroplast envelope. Fatty acids, heme, amino acids, and aromatic isoprenoids are some of the significant compounds synthesized by algal plastids through photosynthetic and biochemical pathways.