Evaluation of antioxidant potential of Emblica officinalis and Murraya koenigii and their role in modulation of cognitive function in diabetic rats

Background: Hyperglycaemia and hyperlipidaemia seen in diabetes mellitus result in oxidative stress and pose significant risk of cognitive decline that may lead to Alzheimer’s disease. Approved anti-diabetic drugs have so far failed to demonstrate anti-oxidant and anti-hyperlipidemic activity, apart from saroglitazar. Therefore, this study was done to find a suitable anti-diabetic drug that possesses anti-hyperglycaemic, anti-oxidant and anti-hyperlipidemic activities and can reverse cognitive decline.Methods: Emblica officinalis (250 mg/kg, p.o. and 500 mg/kg, p.o.) and Murraya koenigii (250 mg/kg, p.o. and 500 mg/kg, p.o.) were chosen to study these activities in Wistar rats. Diabetes was induced by single intraperitoneal injection of streptozotocin [STZ] (50 mg/kg). Fasting blood glucose levels and lipid profile were measured on day 1 and day 30 of the experiment. Cognitive function was assessed by measuring transfer latency (TL) on elevated plus maze, step-down latency (SDL) on passive avoidance apparatus and retention latency (RL) and quadrant time (QT) in Morris water maze. Oxidative stress was assessed at end of study by measuring brain MDA and GSH levels. Cholinergic marker of cognition, AChE was measured in brain at end of study.Results: Both E. officinalis and M. koenigii showed dose dependent anti-hyperglycemic, anti-hyperlipidemic and anti-oxidant effects in diabetic rats with 500 mg/kg dose showing significantly higher effect. Both 250 mg/kg and 500 mg/kg dose of E. officinalis and M. koenigii partially reversed cognitive decline in diabetic rats by day 30.Conclusions: 500 mg/kg p.o. dose of E. officinalis or M. koenigii has potential to reverse cognitive decline in diabetic patients.

Dual application of duckweed and azolla plants for wastewater treatment and renewable fuels and petrochemicals production

Shortages in fresh water supplies today affects more than 1 billion people worldwide. Phytoremediation strategies, based on the abilities of aquatic plants to recycle nutrients offer an attractive solution for the bioremediation of water pollution and represents one of the most globally researched issues. The subsequent application of the biomass from the remediation for the production of fuels and petrochemicals offers an ecologically friendly and cost-effective solution for water pollution problems and production of value-added products. Results: In this paper, the feasibility of the dual application of duckweed and azolla aquatic plants for wastewater treatment and production of renewable fuels and petrochemicals is explored. The differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by these aquatic macrophytes were used as the basis for optimization of the composition of wastewater effluents. Analysis of pyrolysis products showed that azolla and algae produce a similar range of bio-oils that contain a large spectrum of petrochemicals including straight-chain C10-C21 alkanes, which can be directly used as diesel fuel supplement, or a glycerin-free component of biodiesel. Pyrolysis of duckweed produces a different range of bio-oil components that can potentially be used for the production of "green" gasoline and diesel fuel using existing techniques, such as catalytic hydrodeoxygenation. Conclusions: Differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by different aquatic macrophytes can be used for optimization of composition of wastewater effluents. The generated data suggest that the composition of the petrochemicals can be modified in a targeted fashion, not only by using different species, but also by changing the source plants' metabolic profile, by exposing them to different abiotic or biotic stresses

Fungal-assisted algal flocculation: Application in wastewater treatment and biofuel production

Background The microalgal-based industries are facing a number of important challenges that in turn affect their economic viability. Arguably the most important of these are associated with the high costs of harvesting and dewatering of the microalgal cells, the costs and sustainability of nutrient supplies and costly methods for large scale oil extraction. Existing harvesting technologies, which can account for up to 50% of the total cost, are not economically feasible because of either requiring too much energy or the addition of chemicals. Fungal-assisted flocculation is currently receiving increased attention because of its high harvesting efficiency. Moreover, some of fungal and microalgal strains are well known for their ability to treat wastewater, generating biomass which represents a renewable and sustainable feedstock for bioenergy production. Results We screened 33 fungal strains, isolated from compost, straws and soil for their lipid content and flocculation efficiencies against representatives of microalgae commercially used for biodiesel production, namely the heterotrophic freshwater microalgae Chlorella protothecoides and the marine microalgae Tetraselmis suecica. Lipid levels and composition were analyzed in fungal-algal pellets grown on media containing alternative carbon, nitrogen and phosphorus sources from wheat straw and swine wastewater, respectively. The biomass of fungal-algal pellets grown on swine wastewater was used as feedstock for the production of value-added chemicals, biogas, bio-solids and liquid petrochemicals through pyrolysis. Co-cultivation of microalgae and filamentous fungus increased total biomass production, lipid yield and wastewater bioremediation efficiency. Conclusion Fungal-assisted microalgal flocculation shows significant potential for solving the major challenges facing the commercialization of microalgal biotechnology, namely (i) the efficient and cost-effective harvesting of freshwater and seawater algal strains; (ii) enhancement of total oil production and optimization of its composition; (iii) nutrient supply through recovering of the primary nutrients, nitrogen and phosphates and microelements from wastewater. The biomass generated was thermochemically converted into biogas, bio-solids and a range of liquid petrochemicals including straight-chain C12 to C21 alkanes which can be directly used as a glycerine-free component of biodiesel. Pyrolysis represents an efficient alternative strategy for biofuel production from species with tough cell walls such as fungi and fungal-algal pellets

Antihyperlipidemic activity of Chloroxylon swietenia in triton WR1339 induced hyperlipidemia

Background: Medicinal herbs are beneficial and effective either in the management and prevention of several metabolic disorders, associated with hyperlipidemia, hypertension and insulin resistance which increases the cardio-metabolic risk and demands for the life time therapy. Current allopathic medicines are expensive and reported with several adverse effects and hence, finding of a suitable herbal medicine for hyperlipidemic disorders is very important.Methods: Thirty albino rats weighing 200-230g were randomly divided into 5 groups were rendered hyperlipidemia with a single dose of triton WR 1339. Normal control, positive control, standard, aqueous and ethanolic extract groups were treated with tween-80, tween-80, atorvastatin, aqueous and ethanolic extracts of Chloroxylon swietenia respectively for seven days. At the end of the study, blood was collected for estimation of the lipid profile.Results: Both the aqueous and ethanolic extract groups significantly reduced the TG and VLDL levels.Conclusions: The extracts exhibited remarkable activity on one or either parameter of the lipid profile. It could be due to the presence of alkaloids, steroids, flavonoids, coumarins and phenols in the extracts

The microbial removal of toxic waste

The rapid growth of the global chemical industry over the last 35 years has meant that there have been both increased amounts and complexity of toxic waste effluents. Global chemical output increased by 63% in the period from 1996 to 20101; this increase has led to an unprecedented release into the environment of a vast array of chemicals. Bioremediation is now a successful environmental biotechnology used for the remediation of these pollutants, having a number of advantages (for example, cost, environmental friendly means of disposal) over any alternative treatment such as placing in landfill or incineration. Bioremediation offers the opportunity to utilise the natural microbial population to treat the contaminated site, returning the elements making up the contaminants to natural nutrient cycling

Mineralisation of weathered crude oil by a hydrocarbonoclastic consortia in marine mesocosms

Marine waters are most vulnerable to crude oil pollution due to increased sea-based oil-related activities. Successful remediation of such polluted environments is normally carried out in a laboratory with suitable physical and environmental alterations. However, it is challenging to alter the physical and environmental conditions in crude oil-contaminated natural environments. In a previous study, six hydrocarbonoclastic bacteria were isolated from an oil-contaminated site. Here we report on their ability to mineralise weathered crude oil as a carbon source in seawater mesocosms, in order to construct a hydrocarbonoclastic consortia for the effective mineralisation of hydrocarbons present in the weathered crude oil at seawater-based environment. This was completed without altering the physical and environmental parameters (salinity, pH and temperature) and followed by the detection of microbial community changes. The total amount of oil mineralised by these six isolates individually over 28-day incubation ranged from 4.7 to 10 %. The bacterial consortia composed of these six strains showed a greater mineralisation rate (18.5 %). Temperature gradient gel electrophoresis revealed that the functionally dominant species were present after the first week (week 2 to week 4) following the addition of the consortia, which were represented in dendrogram by cluster 2 and also these weeks representing a distinct point on the Pareto-Lorenz curve; no community could be identified in controls in which no consortia were added. This shows that the addition of consortia potentially dealt with changing environmental conditions and preserved its functionality followed by effective mineralisation of weathered crude oil

RNA-TGGE, a tool for assessing the potential for bioremediation in impacted marine ecosystems

Cultivation-independent genomic approaches have greatly advanced our understanding of the ecology and diversity of microbial communities involved in biodegradation processes. However, much still needs to be resolved in terms of the structure, composition and dynamics of the microbial community in impacted ecosystems. Here we report on the RNA activity of the microbial community during the bioremediation process using RNA Temperature Gradient Gel Electrophoresis (RNA-TGGE). Dendrograms constructed from similarity matching data produced from the TGGE profiles separated a community exhibiting high remediation potential. Overall, increased Shannon Weaver Diversity indices (1-2.4) were observed in the high potential remediation treatment samples. The functionality of the microbial community was compared, with the microbial community showing the greatest organisation also showing the highest levels of hydrocarbon degradation. Subsequent sequencing of excised bands from the microbial community identified the presence of Gammaproteobacteria together with a number of uncultured bacteria. The data shows that RNA TGGE represents a simple, reproducible and effective tool for use in the assessment of a commercial bioremediation event, in terms of monitoring either the natural or augmented hydrocarbon-degrading microbial community

A complementary approach to identifying and assessing the remediation potential of hydrocarbonoclastic bacteria

The isolation and assessment of hydrocarbonoclastic bacteria often represents a key strategy in the bioremediation of hydrocarbon-contaminated sites. However the isolation and assessment of such bacteria is often a lengthy and expensive procedure. The aim of this study was to identify potential isolates for use in the remediation of hydrocarbon contaminated sites using a combination of selective isolation plating, the Biolog system and subsequent multivariate analyses