Carbohydrate Content Of Biomass Research Articles

Bioethanol Production From Tropical Marine Microalgae Ambon Bay Navicula sp. of The Inner Ambon Bay Strain

Microalgae are photosynthetic microorganisms that contain carbohydrates can be converted into glucose through a hydrolysis process so that they can be used as raw materials for bioethanol production. Navicula sp. strain TAD is a type of marine microalgae that is spread in the inner Ambon Bay (TAD) sea waters and is used to manufacture bioethanol. This study aims to determine the content of carbohydrates and bioethanol produced from tropical marine microalgae Ambon bay Navicula sp. strain TAD. The research was conducted through several stages, namely the cultivation of Navicula sp. strain TAD to obtain biomass, determine carbohydrate content in biomass, hydrolyze biomass and manufacture bioethanol through a fermentation process using Saccharomyces cerevisiae. The results showed that Navicula sp. strain TAD cultivation for seven days had the highest cell density of 72.167 × 105 ± 0.946 cells mL-1 with dry biomass of 0.933 ± 0.062 g and productivity of 0.166 ± 0.011 gL-1 hour-1. The sulfuric acid hydrolysis process was analyzed for a sugar content of 146.5695 ± 0.758 mg. A fermentation process follows the results of the hydrolysis to produce bioethanol. The bioethanol content obtained was 6.357%. These indicated that Navicula sp. strain TAD has the potential to produce bioethanol

Simultaneous improvements on nutrient and Mg recoveries of microalgal bioremediation for municipal wastewater and nickel laterite ore wastewater

Effects of different mixing ratios between synthetic municipal wastewater (MW) and magnesium (Mg2+)-enriched nickel laterite ore wastewater (NLOWW) on growth of Chlorella sorokiniana (C. sorokiniana), photosynthetic activities, cellular biocomposition, nutrient and Mg2+ removal were investigated in photobioreactors. In the culture without NLOWW, wrinkled cells were observed with low biomass production. The culture mixed with 0.13% NLOWW obtained 1.89-fold higher biomass yield, 3.77-fold enhanced photosynthetic activity (Fv/Fm value), and improved nutrient removal (nitrogen by 102.2%, phosphorus by 39.3%). However, excessive Mg2+ at 100% NLOWW produced highest reactive oxygen species suppressing microalgal growth. The Mg2+ removal capacity increased with NLOWW loading. Moreover, microalgal assimilation primarily contributed to nutrient removal while absorption was the dominant Mg2+ removal pathway. Carbohydrate content in biomass increased with Mg2+ loading. Finally, the approach for MW/NLOWW treatment was demonstrated as economically feasible with revenue of $75.6 per kilogram biomass through a comprehensive economic model.

Complete Acid-Based Hydrolysis Assay for Carbohydrate Quantification in Seaweed: A Species-Specific Optimized Approach.

Accurate quantification of the carbohydrate content of biomass is crucial for many bio-refining processes. The most commonly followed protocol is typically a modification of the NREL-based assay (specifically designed for carbohydrate analysis from lignocellulosic biomass). However, this NREL protocol was revealed to be excessively thermochemically harsh for seaweed biomass. This can result in erroneously low total sugar quantification as the reaction severity can degrade a proportion of the liberated sugars to decomposition products such as furans. Here we describe an optimization of the total acid hydrolysis protocol for accurate quantification of the carbohydrate content of seaweeds. Different species of seaweed can be accurately evaluated for their carbohydrate contents by following this optimized method.

Microalgal biotechnology for greenhouse gas control: Carbon dioxide fixation by Spirulina sp. at different diffusers

The carbon dioxide (CO2) emissions from fossil fuels contributes to global warming. This phenomenon became a major political issue in the fields of science, environment, and economy in current years. Microalgae can convert CO2 into biomass and oxygen through the photosynthesis. The aim of this study was to evaluate the influence of diffusers configuration and CO2 flow rate in mass transfer, CO2 fixation efficiency by Spirulina and in the biomass composition produced. Two flow rates (0.05 and 0.3vvm) and four diffusers (sintered stone (SS), porous curtain (PC), perforated ring (PR) and porous wood (PW)) were used in this study. The maximum CO2 mass transfer coefficient (123.2h−1) in the CO2–H2O system corresponded to the higher flow rate (0.3vvm) using the diffuser porous curtain (PC). The maximum biomass productivity (125.9±5.3mgL−1d−1) was observed for PC with a flow rate of 0.05vvm. Increasing the flow rate (0.3vvm) with PC resulted in a 26% increase in the carbohydrate content in biomass. The results showed a smaller flow rate with porous diffusers might promote an increase in CO2 fixation efficiency by microalgae.

Integrated alkali pretreatment and preservation of wet lettuce (Pistia stratiotes) by lactic acid bacteria for fermentable sugar production

An integrated process was proposed by applying NaOH at high solid condition followed by ensilage to pretreat and preserve the biomass of water lettuce for fermentable sugar production. The results showed that the pretreatment with sodium hydroxide prior the inoculation of lactic acid bacteria effectively removed the lignin content from biomass of water lettuce and increased the extractable portion of the biomass. Experimental sets that had received alkali pretreatment had more total organic acids and fewer butyric acids generated than non-pretreated sets. The results also showed that the integrated process can preserve more carbohydrate content of biomass and can give higher fermentable sugar yields than without pretreatment. Overall, the study suggests that treatment with NaOH improves preservation of fresh harvested water lettuce but further investigation of optimal conditions is needed.

Converting Eucalyptus biomass into ethanol: Financial and sensitivity analysis in a co-current dilute acid process. Part II

Abstract The technical and financial performance of high yield Eucalyptus biomass in a co-current dilute acid pretreatment followed by enzymatic hydrolysis process was simulated using WinGEMS ® and Excel ® . Average ethanol yield per dry Mg of Eucalyptus biomass was approximately 347.6 L of ethanol (with average carbohydrate content in the biomass around 66.1%) at a cost of $0.49 L −1 of ethanol, cash cost of ∼ $0.46 L −1 and CAPEX of $1.03 L −1 of ethanol. The main cost drivers are: biomass, enzyme, tax, fuel (gasoline), depreciation and labor. Profitability of the process is very sensitive to biomass cost, carbohydrate content (%) in biomass and enzyme cost. Biomass delivered cost was simulated and financially evaluated in Part I; here in Part II the conversion of this raw material into cellulosic ethanol using the dilute acid process is evaluated.