Synthesis of biodiesel from non-edible Jatropha curcas oil using potassium hydrogen sulphate-graphene oxide based composite (KHS-GOcat) catalyst

181-187A composite (KHS-GOcat) catalyst has been demonstrated for the synthesis of biodiesel using non-edible Jatropha curcas oil (NEJCoil) as feedstock. Reaction variables are optimized, and maximum biodiesel yield 55 ± 5% obtained under optimum [e.g. KHS-GOcat = 20%, temperature = 70°C, time = 5 h and Methanol/NEJCoil = 9:1] reaction conditions. Synthesis of biodiesel has been confirmed by FT-IR, NMR and GC-MS. The essential fuel properties of the resulting biodiesel are found to be within the limits of ASTM specifications. This work opens new research areas on the development of composite catalysts to maximise the biodiesel production

Synthesis of biodiesel from non-edible Jatropha curcas oil using potassium hydrogen sulphate-graphene oxide based composite (KHS-GOcat) catalyst

A composite (KHS-GOcat) catalyst has been demonstrated for the synthesis of biodiesel using non-edible Jatropha curcas oil (NEJCoil) as feedstock. Reaction variables are optimized, and maximum biodiesel yield 55 ± 5% obtained under optimum [e.g. KHS-GOcat = 20%, temperature = 70°C, time = 5 h and Methanol/NEJCoil = 9:1] reaction conditions. Synthesis of biodiesel has been confirmed by FT-IR, NMR and GC-MS. The essential fuel properties of the resulting biodiesel are found to be within the limits of ASTM specifications. This work opens new research areas on the development of composite catalysts to maximise the biodiesel production

Anionic carboxymethylagarose-based pH-responsive smart superabsorbent hydrogels for controlled release of anticancer drug

Herein, we demonstrate the preparation of superabsorbent hydrogel (CMA-g-PAm) materials using anionic and cold water soluble carboxymethyagarose (CMA, a�seaweed�polysaccharide-based derivative) with polyacrylamide (PAm) through rapid microwave assisted grafting technique. The successful fabrication of CMA-g-PAm was verified by FT-IR, SEM, XRD, TGA and CHN analyzer. Effects of initiator, crosslinker, and monomer on the swelling behavior and grafting parameters have been thoroughly investigated. Moreover, the swelling behavior of the resulting hydrogels was systematically studied, and the results suggested they exhibit excellent pH and salt responsive behavior. The drug delivery application of thus fabricated hydrogel was further evaluated using�doxorubicin�(Dox) as a model drug to explore its possible applications. Release study results revealed that Dox release was significantly accelerated with decrease in pH from 7.4 to 5.0. Toxicity assays confirmed that the blank hydrogels had negligible toxicity to normal cells (VERO), whereas the Dox-loaded hydrogels remained high in cytotoxicity for A549 and Hep-G2�cancer cells. All of these attributes implied that the new proposed hydrogel (HK11) serves as potential drug delivery platforms for cancer therapy.by Huma Khana, Jai Prakash Chaudhary and Ramavatar Meen

Agar/sodium alginate-<i>graft</i>-polyacrylonitrile, a stable hydrogel system

1085-1090Polyacrylonitrile grafted agar/sodium alginate (Agar/Na-Alg-graft-PAN) has been synthesized in aqueous medium under reflux conditions in the presence of potassium persulphate as a free radical initiator. By varying the reaction parameters, e.g., concentrations of acrylonitrile monomer and K2S2O8, reaction time and temperature, the optimum grafting conditions have been identified as that having the highest grafting ratio (Gr 1.87), total conversion (Ct 1.05) and grafting efficiency (Ge 0.89). The blend and grafted products have been characterized by FT-IR, X-ray diffraction, differential scanning calorimeter and scanning electron microscopy. The swelling capacity of Agar/Na-Alg-graft-PAN is found to be 8.5g/g at pH 1.2 and the swelled material is stable for over 24 h. This copolymer hydrogel system may be exploited in various applications utilizing its swelling properties and stability

Graded agaroses directly from seaweed biomass: a sustainable tool for developing clean chemical process

Here we describe few novel grading agents (GrA) for the production of graded agaroses directly from seaweed aqueous extract under ambient conditions. Graded agaroses exhibits gelling properties in a wider range (gel strength ≥100–≥1600 gcm−2, gelling temperature ≤27–≥35 °C, and melting temperature ≤72–≥90 °C) which are essential for a variety of molecular biology applications. The uniqueness of this process is the ability to tailor the essential properties of agarose for desired applications, can be achieved from single seaweed aqueous extract by altering initiator nature and/or concentration (w/w) of an initiator in GrA.by Nilesh Vadodariyaa, Jai Prakash Chaudhary, Hiren D. Ravald and Ramavatar Meen

Antioxidant activity and phytochemical analysis of a few Indian seaweed species

507-518Antioxidant activities of crude methanol extracts and fractions of the seaweed species viz. Bryopsis plumosa (BP), Dictyopteris australis (DA) and Gracilaria pudumadamensis (GP) of Indian waters were evaluated and correlated with their phytochemical contents. In DPPH assays the most promising antioxidant sample was the crude methanol extract (BPM), which was comparable with standard antioxidant BHT. In the superoxide radical activity assays no sample in the group was as active as BHT, however the promising ones were DAM, DAE and GPM, GPE, GPH (subscripts M, E and H stand for the respective methanol extracts and their ethyl acetate and hexane fractions). In the Fe2+ chelating activity assays EDTA showed far stronger activity than those of the promising samples. In reducing power assays BPM, BPE, and BPH showed comparable activity with BHT at a concentration 0.5 mg/mL. Thus these seaweed species would be of potential utility as a source of natural antioxidants

Controlled-release performance of chitosan-polyuronic acid adducts

1269-1274Controlled release performance of chitosan-polyuronic acid (polymannuronic and polyguluronic acid) adducts, has been evaluated using five structurally different drugs, i.e., paracetamol (PCT), indomethacine (IND), isoniazid (INH), atenolol (ATN) and pravastatin (PST). The release rates of PCT, INH and ATN, all containing  -NH-CO-moieties, show an inverse correlation with the change in pH, i.e., highest at <span style="mso-bidi-font-weight: bold">p<span style="mso-bidi-font-weight:bold;mso-bidi-font-style: italic">H 1.2 and lowest at p<span style="mso-bidi-font-weight: bold;mso-bidi-font-style:italic">H 7.4. A reversed trend is noted with IND and PST, having no -NH-CO-moieties; the release rates are highest at <i style="mso-bidi-font-style: normal">pH 7.4 and lowest at <span style="mso-bidi-font-weight: bold">p<span style="mso-bidi-font-weight:bold;mso-bidi-font-style: italic">H 1.2. This appears to have a correlation with the structural features of the adducts and the drugs alike, containing -NH-CO-groups, manifesting pH-dependent preferential interactions of -NH-CO-groups through intermolecular hydrogen bonding facilitated at a higher p<span style="mso-bidi-font-weight: bold;mso-bidi-font-style:italic">H. This study presents an array of biopolymer-based materials, which can be harnessed for delivering specific dosage schedules and would be of potential utility in pharmaceutical formulations. </span

Clinico-radiological profile and risk factors in patients with anthracosis

Background: Anthracosis is the black pigmentation of the mucosal lining of the tracheo-bronchial tree. The significance of this finding is not known and often ignored. The aim of the present study is to find the association of anthracosis with demographic variables, biomass fuel and occupational exposure, respiratory diseases, radiological pattern and functional morbidity. Materials and Methods: Enrolment of the subjects for the study was done at SMS hospital, Jaipur. Patients with anthracosis evident on bronchoscopy were included as the cases. Patients without anthracosis on bronchoscopy, matched according to age, gender and smoking habits, were included in the control group. Subjects in both the arms completed a questionnaire and also underwent computed tomography (CT) of the chest and six minute walk test (6MWT). Results: Thirty cases and 53 controls were included in the study. The patients with anthracosis presented with symptoms ranging from cough (76.65%), hemoptysis (46.6%), fever (26.6%), dyspnea (90%) and malaise (73.3%). Biomass fuel exposure for the cases was 35.13 ± 55.86 hours in a year and for the controls was 28.15 ± 40.09 hours in a year (P > 0.05). Stone mining was significantly associated with anthracosis (P < 0.05). CT chest revealed fibrosis (43.3%), consolidation (33.3%), cavitation (16.6%) and mass (46.6%) in the cases. Sixty percent of cases and 15% of controls were diagnosed to have either old or active pulmonary tuberculosis (P < 0.05). Conclusions: Anthracosis is associated with pulmonary tuberculosis. Biomass exposure is not significantly associated with anthracosis. Post tubercular fibrosis is more common on CT chest of patients with anthracosis

Superior quality agar from red alga Gelidiella acerosa (Rhodophyta, Gelidiales) from Gujarat coast of India: An evaluation

268-274Physicochemical and rheological properties of agars extracted from 20 samples of Gelidiella acerosa collected from Gujarat coast in various seasons have been evaluated. The agar yields varied significantly (8.5–40.4%). The gel strength values were in the range of 200-700 g cm⁻² (1.5% gel at 20ºC) having gelling temperatures 36-41ºC. It was observed that agar obtained from Gelidiella acerosa of Okha, in almost all seasons has superior physicochemical and rheological properties than the rest of the samples. The 3,6-anhydrogalactose (3,6-AG) and sulphate content too varied significantly among the agar of each place. It was observed that the better quality agar has relatively lower sulphate and higher 3,6-anhydrogalactose contents. Therefore, Gelidiella acerosa of Okha can be used as a good source of agar. Rheological data of the best agar of the lot were also in good agreement with the other physicochemical data e.g., high gel strength agar showed higher G' value and vice versa

Experimental cultivation of <em>Gelidium pusillum</em> in open sea along the south east Indian coast

336-345Experimental cultivation of Gelidium pusillum was attempted in the south east coast of India with three different cultivation methods to enhance the biomass production for obtaining superior quality agar with high gel strength. The maximum biomass yield (0.465 ± 0.34 kg.fr.wt m-2) was recorded in net bag method whereas minimum biomass yield (0.144 ±0.03 kg.fr.wt m-2) was recorded by net pouch method. Similarly, Daily Growth Rate (DGR) was more in net bag method (1.05 ± 0.529 %) than raft (0.679 ± 0.13 %) and net pouch (0.56 ± 0.256 %).  Furthermore, best quality agar was obtained by net bag method [high gel strength: 2100 ± 50 g cm-2 in 1.5 % gel; gelling temperature: 35 ± 1 oC; ash content: ≤1 %; sulphate content: ≤0.34 %] essential for potential superior quality agar applications