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The growing demand have made researchers look into algae-based biodiesel, which is precisely a type of algae called Botryococcus braunii, as an alternate to sustainable fuel source. The feature of this alga is that it has high oil content and is determined as user friendly. The study made an attempt to explore the effectiveness and efficiency of adding hydrogen with Botryococcus braunii at 2 different rates, viz., 4LPM and 8LPM respectively in a Common Rail Direct Injection (CRDI) diesel engine and compared its performance with the pure diesel. This assessment approach of testing hydrogen (H 2 ) with 30% Botryococcus braunii biodiesel + 70% diesel blend combination (A30) and comparing the same with pure diesel is regarded as the primary creativity and uniqueness of this research investigation. The analysis of the study revealed the fact that adding hydrogen to 30% Botryococcus braunii biodiesel + 70% diesel blend enhanced the performance of the engine substantially. It further demonstrated that the Brake Thermal Efficiency improved to 37% from 31% with the addition of A30 + H 2 (8 LPM) against the pure diesel, marking a rise of 19.35%. Similarly, specific fuel consumption dropped to 0.24 kg/kWh from 0.30 kg/kWh, illustrating a reduction of 20%, in comparison with pure diesel. Volumetric efficiency surged to 91% (with a rise of 10.98%) from 82%. This is because of the presence and availability of more content of oxygen in 30% Botryococcus braunii biodiesel + 70% diesel blend, facilitating a better and a clean process of combustion. The study focused on the properties of combustion improved with the in-cylinder pressure at the utmost load, where it was found rising to 77.3 bar from 70.2 bar, indicating a marginal surge of 10.11% against the net heat release rate, demonstrating a steep rise of 18.26% (increased to 48.63 kJ/m 3 deg from 41.11 kJ/m³deg). Besides the above, the Carbon Monoxide (CO) emissions reduced by 69.46% (0.334% to 0.102%), Hydrocarbons decreased by 43.24% (148ppm to 84ppm), CO 2 dropped by 7.77% (10.3% to 9.5%), smoke opacity diminished by 14.18% (69.1% to 59.3). It was evidently observed that the hydrogen blend algae biodiesel enhanced a better combustion process by the removal of incomplete combustion areas and enhancing the overall performance and efficiency of the engine. It is noted that while the outcomes of the emissions reveal substantial enhancements, Nitrogen oxides (NO X ) emissions do increase by 47.64% (from 1503ppm to 2220ppm). The exhaust gas temperature is decreased marginally from 520 °C to 498 °C, marking a reduction of 4.23%. In a nutshell, the study apparently reveals the fact that A30 + H 2 (8 LPM) significantly improves the performance of the engine, enhances the characteristics of combustion and minimizes most emissions leading to a very high and an efficient sustainable fuel in contrast to the pure diesel.

Background Recent understanding that specific algae have high hydrocarbon production potential has attracted considerable attention. Botryococcus braunii is a microalga with an extracellular hydrocarbon matrix, which makes it an appropriate green energy source. Results This study focuses on extracting oil from the microalgae matrix rather than the cells, eliminating the need for an excessive electric field to create electro-permeabilization. In such a way, technical limitations due to high extraction energy and cost can be overcome. Here, nanosecond pulsed electric fields (nsPEF) with 80 ns duration and 20-65 kV/cm electric fields were applied. To understand the extraction mechanism, the structure of the algae was accurately studied under fluorescence microscope; extraction was quantified using image analysis; quality of extraction was examined by thin-layer chromatography (TLC); and the cell/matrix separation was observed real-time under a microscope during nsPEF application. Furthermore, optimization was carried out by screening values of electric fields, pulse repetition frequencies, and energy spent. Conclusions The results offer a novel method applicable for fast and continues hydrocarbon extraction process at low energy cost.

Botryococcus braunii (B. braunii) is a green microalga primarily found in freshwater, reservoirs, and ponds. Photosynthetic pigments from algae have shown many bioactive molecules with therapeutic potential. Herein, we report the purification, characterization, and anticancer properties of photosystem I light-harvesting complex I (PSI-LHCI) from the green microalga B. braunii UTEX2441. The pigment–protein complex was purified by sucrose density gradient and characterized by its distinctive peaks using absorption, low-temperature (77 K) fluorescence, and circular dichroism (CD) spectroscopic analyses. Protein complexes were resolved by blue native-PAGE and two-dimensional SDS-PAGE. Triple-negative breast cancer MDA-MB-231 cells were incubated with PSI-LHCI for all of our experiments. Cell viability was assessed, revealing a significant reduction in a time- and concentration-dependent manner. We confirmed the internalization of PSI-LHCI within the cytoplasm and nucleus after 12 h of incubation. Cell death mechanism by oxidative stress was confirmed by the production of reactive oxygen species (ROS) and specifically superoxide. Furthermore, we monitored autophagic flux, apoptotic and necrotic features after treatment with PSI-LHCI. Treated MDA-MB-231 cells showed positive autophagy signals in the cytoplasm and nucleus, and necrotic morphology by the permeabilization of the cell membrane. Our findings demonstrated for the first time the cytotoxic properties of B. braunii PSI-LHCI by the induction of ROS and autophagy in breast cancer cells.

Hydrocarbons are easily extracted by organic solvents such as n-decane from wet samples of Botryococcus braunii by thermal pretreatment at 90 degree C even after being cooled to room temperature. However, hydrocarbon recoveries are not as readily achieved at room temperature from samples pretreated at temperatures lower than 80 degree C. This suggests that there is the point of no return for pretreatment temperature that enables effective solvent extraction of hydrocarbons at room temperature from wet algal samples of B. braunii. To elucidate the mechanism of hydrocarbon recovery from B. braunii following thermal pretreatments, we investigated the thermophysical properties of the water phase separated from heated algal slurry. Differential scanning calorimetry (DSC) measurements revealed sol-gel transitions in the water phase of algal slurry after protein denaturation at 64 degree C in samples that was pretreated at 70 or 80 degree C but not in those pretreated at 90 degree C. Furthermore, the pretreated >70 degree C water-soluble polymers revealed polysaccharides composed of galactose, arabinose, and uronic acid. These results suggest that the transition from sol state to gel state of water-soluble polysaccharides in algal slurry prevented hydrocarbon recovery with organic solvents since hydrocarbons were easily recovered from sol state samples pretreated at 70 or 80 degree C when the extraction temperature was kept the same as the pretreatment temperature. These results reveal that the presence of water-soluble polymers with gelation ability in the water phase and removal of these polymers in sol state enable effective recovery of hydrocarbons at room temperature after thermal pretreatments.

The freshwater green alga Botryococcus braunii produces long-chain hydrocarbon oil in large quantities and secretes these from the cells. To exploit B. braunii as a source of next-generation biofuel, development of cost-effective cultivation systems are required. One of the most cost-effective methods for large-scale production is to simply grow B. braunii in open ponds. However, trials to cultivate B. braunii in open ponds often fail due to thriving of other green algal and cyanobacterial species because of the relatively slow growth of B. braunii. We previously demonstrated that herbicides are effective in control of contaminating algae. In order to use herbicide-assisted cultivation systems, we generated herbicide-resistant mutants of an oil-rich strain of B. braunii race B (strain BOT-22) by ethyl methanesulfonate mutagenesis. We isolated 44 glufosinate-resistant and 21 methyl viologen-resistant mutant lines. Some of these mutant lines exhibited vigorous growth and oil production in herbicide-containing liquid media, suggesting that they can be directly used in herbicide-containing cultivation systems.

Botryococcus braunii has an outstanding ability to produce lipid; however, it is a slow-growing green microalgae. Statistical optimization of growth media was performed to faster growth and to increase lipid concentration. The effect of media composition on the growth of B. braunii LB572 was examined using fractional factorial design and central composite design. The media components examined include sodium carbonate, potassium phosphate, calcium chloride, magnesium sulfate, ferric citrate, and sodium nitrate. The results indicated that potassium phosphate and magnesium sulfate were major impact factors. The optimum concentrations of potassium phosphate and magnesium sulphate were found to be 0.058 and 0.09 g/L, respectively, for growth and 0.083 and 0.1 g/L, respectively, for lipid production. These values were validated using bubble column photobioreactors. Lipid productivity increased to 0.19 g/L/day in lipid-optimized media, with an average biomass productivity of 0.296 g/L/day and 64.96% w/w. In growth-optimized media, lipid productivity was 0.18 g/L/day, with an average biomass productivity of 0.304 g/L/day and 59.56% w/w.

Microalgae are a very diverse group of organisms that consist in both prokaryotic and eukaryotic forms. Some species of microalgae can be induced to overproduce particular fatty acids through simple manipulations of the physical and chemical properties of the culture medium. In this paper, the effect of different extraction techniques on the recovery of fatty acids from the freeze-dried biomass from two lipid-producing microalgal strains: Botryococcus braunii LB 572 (green algae) and Synechocystis sp. PCC 6803 (cyanobacteria) was examined. Five procedures were used: after conversion of the lipid material into the corresponding fatty acid methyl esters (FAMEs) via suitable derivatization reactions (extraction-transesterification) and direct transesterification of biomass to produce FAMEs (without the initial extraction step) that used differential types of catalysts and processing conditions. This study has shown that procedure 3, a one step practical procedure for lipid extraction and in situ methyl ester derivation could be used successfully for the determination of the fatty acid compositions of microalgae and cyanobacteria.

Microalgae is a promising next-generational energy. In this research, we focus on oil-extracted Botryococcus braunii residues collected by adding polysilicato-iron (PSI) as a flocculant followed by carbonization under argon atmosphere. We conducted carbonization at various temperatures as a first attempt to reveal the fundamental properties of the carbonization process of the microbes. The carbons thus obtained by heat treatment at 900 °C present a unique magnetic behavior due to reduced magnetite (Fe3O4) inclusion, which is produced from polysilicato iron (Fe2O3) during the heating process. Experimental results suggest that this carbonic material can be applied as a heavy metal-capturing carbon and magnetic porous substrate catalyst. The effective use of the waste may open a new avenue for an energy-microbiology-materials system.

Plant secondary metabolites are produced naturally in the plant system as a defense mechanism to combat environmental stress factors. These metabolites are extensively used in food, cosmetics, agrochemicals and pharmaceutical sectors. With the applications of plant tissue culture, any particular organ which is the major site for secondary metabolite production can be targeted and cultured. Recently, a new strategy to increase the metabolite production in plants has been employed with the use of elicitors. These elicitors are the chemical substances that trigger the biosynthetic pathways by activating certain transcriptional factors and upregulating the genes. Hence the secondary metabolite production increases in the plant system due to the stress developed by the introduction of the elicitors. Generally, elicitors may be abiotically derived from non-living sources or biotically derived from the living sources. In the present review, the mechanism of biotic elicitation and the applications of biotic elicitors like bacterial, fungal, algal elicitors and other polysaccharides extracted from them has been discussed extensively. It has been noted that the addition of bacterial elicitors like Rhizobiumrhizogenes showed a 94% increase in genistein production while Escherichia coli showed a 9.1-fold increase in diosgenin production. Similarly, fungal elicitors like Aspergillus niger increased thiophene production by 85% and a 26-fold increase in sanguinarine production was seen when the cultures were treated with Botrytis sps. Algal extracts like Haematococcus pluvialis increased the betalain production by 2.28 folds while Botryococcus braunii elicited Vanillin, Vanillylamine and Capsaicin by 3-fold, 6-fold and 2.3-fold respectively.

Extracts of Botryococcus braunii and Nannochloropsis oculata were evaluated for inhibitory activity against acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase (TYRO) and capacity to attenuate hydrogen peroxide (H sub(2)O sub(2))-induced injury in the human dopaminergic cell line SH-SY5Y. We also report the antioxidant activity, the total phenolic content (TPC) and the fatty acid (FA) profile of these microalgae. Both species had low levels of TPC and considerable amounts of polyunsaturated fatty acids (PUFA). The highest radical scavenging activity (RSA) against 1,1-diphenyl-2-picrylhydrazyl (DPPH) was observed in the acetone extract of B. braunii and in the diethyl ether extracts of both strains. The acetone extract of B. braunii had the highest RSA against 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid). The extracts had a higher capacity to chelate iron than copper, and the highest iron chelation was achieved with the hexane extract of N. oculata. The diethyl ether and water extracts of the latter species also displayed the highest copper chelation. Except for the acetone extract of B. braunii and the water extract of N. oculata, all samples inhibited AChE, especially the hexane extract of N. oculata. Samples had moderate BChE inhibition and no effect towards TYRO. Almost all samples effectively protected neuronal cells against oxidative stress induced by H sub(2)O sub(2). These results suggest possible novel applications of biomass from those microalgae in the pharmaceutical industry and/or as functional foods.