Bioethanol Production from Sweet Sorghum Bagasse Through Enzymatic Process

Comparison of the effects of five pretreatment methods on enhancing the enzymatic digestibility and ethanol production from sweet sorghum bagasse

Oil palm empty fruit bunches (OPEFBs) are highly abundant in Indonesia and have been highlighted as a potential feedstock for bioethanol and xylitol production. However, the efficacy of the fermentation technology to convert OPEFBs to bioethanol and xylitol, either in partial (i.e. mono-production) or integrated (i.e. co-production) process, still needs further improvement. This study aimed to evaluate the partial and integrated process for xylitol and bioethanol production from OPEFBs. In the integrated process, the remaining solid residues after xylitol extraction are used as feedstock for bioethanol due to their high cellulose compounds. This solid residue is more susceptible to be degraded by cellulase enzymes into glucose and further transformed into bioethanol. In the partial process of xylitol production, xylanase enzyme was used to hydrolyze xylan into xylose, which was then converted into xylitol using Debaryomyces hansenii. While in the partial process of bioethanol production, the hydrolysis of cellulose in the OPEFB into glucose was carried out using cellulase enzymes, followed by fermentation using Saccharomyces cerevisiae. The results show that the partial process produced xylitol yield (Yp/s) of 0.10 g-xylitol/g-xylose, while bioethanol at yield (Yp/s) of 0.32 g-bioethanol/g-glucose, respectively. The integrated process generates xylitol yield (Yp/s)of 0.298 g-xylitol/g-xylose, with bioethanol yield from the remaining solid at 0.051 g-bioethanol/g-OPEFB (or 0.078 g-bioethanol/g-glucose). These findings, therefore, confirmed that the integrated process of xylitol with bioethanol production might offer higher efficacy of OPEFB utilization into high value-added products.

Sweet sorghum bagasse (SSB) obtained after juice extraction is a potential feedstock for fermentable sugars production that can be further fermented to different kinds of products, such as ethanol or lactic acid. The proper particle size resulted from phsyical pretreatment and different pretreatment processes including water, alkali, hydrothermal, and alkali hydrothermal for improving enzyme susceptibility of SSB have been investigated. After grinding to particle sizes of <250 ?m, 250-420 ?m, and, > 420 ?m the sweet sorghum bagasse was washed to eliminate residual soluble sugars present in the bagasse. Dosages of cellulase enzyme used in saccharification were 60 and 100 FPU/g substrate, respectively. The results showed that SSB with particle sizes of 250-420 ?m had the highest cellulose (38.33%) and hemicellulose content (31.80%). Although the yield of reducing sugar of 250-420 ?m size particles was lower than that of smaller particle (<250 ?m), the former was more economical in the energy consumption for milling process. The yields of reducing sugar obtained from enzymatic hydrolysis of alkali hydrothermal pretreated sweet sorghum bagasse were 1.5 and 0.5 times higher than that from untreated sweet sorghum bagasse at enzyme loading of 100 and 60 FPU/g substrate, respectively. Furthermore, alkali hydrothermal pretreatment was able to remove as much as 85% of lignin. Morphological analysis using SEM (Scanning Electron Microscope) showed that samples treated with alkali hydrothermal have more pores and distorted bundles than that of untreated sweet sorghum bagasse. Meanwhile, XRD (X-ray diffraction) analysis showed that pretreated samples had a higher crystallinity and smaller crystallite size than untreated sweet sorghum bagasse, which might be due to removal of amorphous lignin components.

The definition and function of inventory management reveal the importance of modern industry in formulating policies that regulate the supply of raw materials, semi-finished products, and finished products. Unfortunately, most companies fail to consider the characteristics of their raw materials when determining inventory strategies. Raw materials that are perishable are those that consider their service life and storage time. Inventory management plays a crucial role in supply chain management, especially for perishable raw materials, such as food products. PT X, a food business in Padang, experienced difficulty in meeting the demand for rendang products due to a lack of raw materials. Therefore, this study aims to develop an inventory management model that takes into account the perishable raw materials' expiration time. The model development consists of three stages: model development design, inventory model formulation, and model testing. The proposed model resulted in a storage time interval of five days and an optimal order quantity of 34 kg of meat with a safety stock of 14 kg. Implementing this model led to lower total inventory costs for PT X than the actual conditions of the company. The total inventory cost obtained using this model is Rp279,797,822. This study emphasizes the importance of considering the characteristics of raw materials in determining inventory strategies to optimize inventory management effectively and efficiently. The study's findings can serve as a reference for other food businesses encountering similar inventory management challenges in the perishable food industry.

Current fossil fuel reserves cannot keep up with the world’s need for fuel, leading to a global energy crisis. The issue raises attention to renewable energy sources. Indonesia has committed to using 15% bioethanol in gasoline mixture by 2025, as outlined in Presidential Decree No. 5 of 2006. This article discusses past studies on sweet sorghum plants in their use as a raw material for bioethanol production from various aspects. The study shows that sweet sorghum juice has a high potential to be converted into bioethanol due to its high sugar content. Pretreated sweet sorghum seeds and bagasse also have great potential to be converted into bioethanol due to their rich oligomer and polymer sugar content. The main challenge of producing bioethanol from sweet sorghum is the low economic competitiveness of utilizing sweet sorghum as an energy crop compared to using sweet sorghum as a food crop. The present study focuses on the mass balance analysis of bioethanol production from sweet sorghum. It is expected that the results of the present study may give a preliminary overview of the bioethanol production potential from sweet sorghum.

In vivo cadmium-assisted dilute acid pretreatment of the phytoremediation sweet sorghum for enzymatic hydrolysis and cadmium enrichment

Pretreatment of cassava stems and peelings by thermohydrolysis to enhance hydrolysis yield of cellulose in bioethanol production process

The presented study has been carried out in order to study the quality of Alkali Treated Cottonii (ATC) made from Eucheuma cottonii which being collected from different regions in Indonesia (Belitung, Nusa Tenggara Barat and Lampung). The quality variables analyzed were the characteristics of raw materials (Clean anhydrous weed and impurities) and the characteristics of ATC produced (moisture content, ash content, acid insoluble ash content, yield, gel strength, sulphate content, gelling -melting point). The analysis was done in 3 replicates and the data were statistically analyzed using SPSS 15 package software. Results indicated that the raw material from Lampung had a better quality than those from Nusa Tenggara Barat and Belitung. In addition, the characteristics of ATC produced from these three raw materials showed that seaweed from Lampung produced better quality ATC than those from Nusa Tenggara Barat and Belitung in terms of their gel strength, sulphate content and yield.

The composition of 321 pieces of Neolithic pottery samples in Liaoxi Area was detected by X-ray fluorescence analyzer, and the characteristics of raw materials in different periods were analyzed by principal component analysis. The results show that the raw materials of ceramic samples are ordinary fusible clay with low SiO2 and high flux RxOy. The composition of pottery from Chahai site of Xinglongwa culture is quite different from that in other areas. The contents of Fe2O3 and MgO are obviously higher, while the contents of SiO2, Al2O3 and K2O are lower. The raw materials used for making pottery are relatively poor.

Abundant lignocellulosic biomass from municipal solid waste (MSW) is comprised of 40 % waste paper, which can be utilised to produce bioethanol, a renewable energy resource to reduce fossil fuel use. Eventhough lignocellulosic biomass provides a low cost resource, it is very difficult to convert into bioethanol and this results in the cost of bioethanol production being commercially unfeasible. Production of bioethanol from lignocellulosic biomass consists of two steps. The first step converts the biomass to fermentable sugars by hydrolysis. This is followed by microbial fermentation of the sugars to bioethanol. The objective of this study was to investigate hydrolysis of two types of waste paper, namely, office paper and newspaper, to produce fermentable sugars using the enzyme cellulase. Enzymatic hydrolysis of waste paper is affected by numerous factors such as reaction time, enzyme/paper ratio, pretreatment and smfactant addition. A type of statistical design, i.e. Low Cost Response Smface Method (LCRSM) was used to study the main and interactive effects among the four significant factors of reaction time (4-20 h), enzyme/paper ratio (2-18 % ), H₃PO₄ pretreatment (0-8 g/L), smfactant concentration (0-8 g/L for office paper and 0-12 g/L for newspaper) on sugar production efficiency. This method was proposed because it is comparable to other conventional experimental design methods with much lesser time, cost and effort in optimising the four variables to give the maximum sugar yield. The optimum conditions for office paper were obtained as follows: reaction time = 20 hours, enzyme/paper ratio = 18 %, H₃PO₄ = 8 g/L, surfactant = 4.2 g/L and predicted sugar yield = 86.6 %. For newspaper, the optimum conditions were: reaction time= 20 hours, enzyme/paper ratio= 18 %, H₃PO₄ = 8 g/L, surfactant= 6.8 g/L and predicted sugar yield= 18 %.The predicted sugar yields obtained with a commercial software package are similar to those predicted using Genetic Algorithms (GAs) and in good agreement with experimental sugar yields of 82.2 % and 17 .13 % measured under the predicted optimum conditions for office paper and newspaper respectively. Reaction time is a dominant factor as longer time periods are required for efficient interaction between cellulase and cellulose. Enzyme/paper ratio is another important factor because cellulase breaks down cellulose into reducing sugars. However, the rate of reaction is influenced by the strnctural features of cellulose. The structural features that govern the susceptibility of cellulose to enzymatic attack include: (1) the amount of lignin content, (2) the degree of crystalline portion, (3) moisture content of cellulose and (4) the accessible areas between the microfibrils for cellulase molecules to penetrate through. Pretreatment has to be applied prior to hydrolysis. H₃PO₄ pretreatment was not so effective with substrate containing lignin, but is able to reduce the level of crystallinity of cellulose and further increase the accessible area. Therefore,…

The paper examines the relationship between the activity of cellulase and xylanase enzymes and the lactic acid yield which was synthesized by the fungus Rhizopus oryzae F-1030 during its cultivation on a culture medium based on catalytically modified neutral sulfite liquors. It was shown that in cultivating by the deep method the fungus R. oryzae F-1030 synthesizes xylanase and cellulase enzymes that break down polysaccharides in a nutrient medium to simple sugars which are easily accessible for assimilation by the fungus. Accordingly, the fungus R. oryzae F-1030 can be used as a promising biotechnological object for the bioconversion of cellulose production secondary resources. It was found that the level of cellulase and xylanase expression in R. oryzae F-1030 depends on the type of substrate. The xylanase activity of the fungus is more pronounced than the cellulase activity since xylan oligomers predominate in birch wood. It was noted that the lactic acid yield during the cultivation of the fungus R. oryzae F-1030 on a catalytically modified neutral sulfite liquor depends on the action specifics of the hydrolyzing catalyst. As a nutrient medium for the microbiological synthesis of lactic acid the fungus R. oryzae F-1030 can use biocatalytically treated liquors of birch wood neutral sulfite pulping.

Energy consumption has increased rapidly because the world population has grown, so has energy consumption for industrial needs. Now Indonesia still uses fossil fuels as the main energy source, because of their non-renewable nature, the continuous use of fossil fuels causes scarcity problems. Bioethanol production is currently getting more intense, this is because there are several factors that cause it to be more intense, namely market stability, low costs, sustainability, the composition of alternative energy fuels and the catastrophic depletion of fossil fuels. Sago waste can be used as an environmentally friendly renewable resource. Bioethanol production process from sago waste using enzymes and fermentation with the help of microorganisms. The bioethanol production process from sago waste has four main parts. The first thing to do is the pre-treatment process, namely drying the sago pulp and delignification process. Samples from the delignification process will then be used in the hydrolysis process with a catalyst in the form of HCl. The results of the hydrolysis were fermented at a pH of 5 and tape yeast was added. Then in the distillation process requires filtrate which was then evaluated qualitatively using K2Cr2O7 reagent. The mixture derived from the fermentation process using baker's yeast and wet sago pulp can produce bioethanol levels up to 45.70%. The process of making bioethanol from sago waste through a baker's yeast fermentation process is expected to help advance the bioethanol production process as a renewable energy source in Indonesia.

The Pirro Nord site (Apricena, Fg, Southern Italy) in the context of the first European peopling: Convergences and divergences

Sweet sorghum bagasse (SSB) is potential feedstock for bioethanol production due to its natural abundance and high cellulose content (> 40%). This work compared the impact of three variables relative to the enzymatic hydrolysis of SSB kraft pulp. The three variables were the biosurfactant from lignin derivative known as amphiphilic lignin derivatives (A-LD), the enzyme loading level, and the hydrolysis time. These variables were optimized by response surface methodology (RSM) with a Box-Behnken design (BBD). The concentration of polyethylene glycol (PEG) 4000 was also optimized to compare it with the A-LD performance in the enzymatic hydrolysis process. After optimization, the A-LD produced a higher reducing sugar yield (RSY) (99.45%) than the PEG 4000. The difference in the predicted versus experimental values of the RSY was less than 4%, which means that the model was highly predictive. The adequacy of the model was confirmed by a regression value close to 1 for the A-LD assisted test. The result implies that the A-LD significantly improved the enzymatic hydrolysis performance to enhance the RSY. Moreover, the BBD is adequate and useful to identify the optimum concentration of surfactant.

The utilization of abundantly available lignocellulosic biomass requires an efficient cellulolytic enzyme system. Evaluation of an efficient microbial system is a crucial part for the development of useful enzyme production in an industrial process. The present study reports the production of cellulolytic enzymes from various lignocellulosic biomasses by Trichoderma harzianum strain HZN11 characterized by 18S rDNA sequencing. The organism revealed a well-balanced cellulolytic complex of enzyme production (endoglucanase 30.32 U g−1, exoglucanase 15.08 U g−1, FPase 5.56 U g−1, cellobiase 17.92 U g−1, β-glucosidase 11.21 U g−1, and xylanase 1740 U g−1) from sweet sorghum bagasse under solid-state fermentation. Statistical optimization by Plackett–Burman design constituting of 12 experimental runs at two levels of seven independent variables revealed the significant effect of four variables, namely, protease peptone, lactose, MgSO4·7H2O, and K2HPO4 on endoglucanase production at 95% confidence level with R 2=97.68%. Response surface methodology using central composite design was employed with 31 experimental runs at 5 levels with 4 significant independent variables. The responses in the form of contour and 3D plots showed significant interaction effects. Significant interactions existed between the variables at p < 0.05 with R 2=97.3%. The model generated through these designs was validated giving a 2.31-fold increase in endoglucanase production. The isolated T. harzianum strain HZN11 produced an efficient pool of cellulolytic enzymes which is essential for efficient hydrolysis of biomass. The strain HZN11 also possessed a significant capability of cellobiase production which is usually deficient in other strains. Higher yields of endoglucanase could be employed for bioethanol production.