scholarly journals Sustainable Second-Generation Bioethanol Production from Enzymatically Hydrolyzed Domestic Food Waste Using Pichia anomala as Biocatalyst

2020 ◽  
Vol 13 (1) ◽  
pp. 259
Author(s):  
Ioanna Ntaikou ◽  
Georgia Antonopoulou ◽  
Gerasimos Lyberatos

In the current study, a domestic food waste containing more than 50% of carbohydrates was assessed as feedstock to produce second-generation bioethanol. Aiming to the maximum exploitation of the carbohydrate fraction of the waste, its hydrolysis via cellulolytic and amylolytic enzymatic blends was investigated and the saccharification efficiency was assessed in each case. Fermentation experiments were performed using the non-conventional yeast Pichia anomala (Wickerhamomyces anomalus) under both separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) modes to evaluate the conversion efficiencies and ethanol yields for different enzymatic loadings. It was shown that the fermentation efficiency of the yeast was not affected by the fermentation mode and was high for all handlings, reaching 83%, whereas the enzymatic blend containing the highest amount of both cellulolytic and amylolytic enzymes led to almost complete liquefaction of the waste, resulting also in ethanol yields reaching 141.06 ± 6.81 g ethanol/kg waste (0.40 ± 0.03 g ethanol/g consumed carbohydrates). In the sequel, a scale-up fermentation experiment was performed with the highest loading of enzymes in SHF mode, from which the maximum specific growth rate, μmax, and the biomass yield, Yx/s, of the yeast from the hydrolyzed waste were estimated. The ethanol yields that were achieved were similar to those of the respective small scale experiments reaching 138.67 ± 5.69 g ethanol/kg waste (0.40 ± 0.01 g ethanol/g consumed carbohydrates).

2021 ◽  
Vol 2 (2) ◽  
pp. 237-253
Author(s):  
Raffel Dharma Patria ◽  
Jonathan WC Wong ◽  
Davidraj Johnravindar ◽  
Kristiadi Uisan ◽  
Rajat Kumar ◽  
...  

The present work evaluates the techno-economic feasibility of a rhamnolipids production process that utilizes digestate from anaerobic digestion (AD) of food waste. Technical feasibility, profitability and extent of investment risks between fermenter scale and its operating strategy for rhamnolipids production was investigated in the present study. Three scenarios were generated and compared: production using a single large fermenter (Scenario I), using two small fermenters operated alternately (Scenario II) or simultaneously (Scenario III). It was found that all the scenarios were economically feasible, and Scenario III was the most profitable since it allowed the most optimum fermenter operation with utilization of multiple small-scale equipment to reduce the downtime of each equipment and increase the production capacity and overall productivity. It had the highest net present value, internal rate of return and shortest payback time at a discount rate of 7%. Finally, a sensitivity analysis was conducted to indicate how the variation in factors such as feedstock (digestate) cost, rhamnolipids selling price, extractant recyclability and process capacity influenced the process economics. The work provides important insights on techno-economic performance of a food waste digestate valorization process which would be useful to guide its sustainable scale-up.


2021 ◽  
Vol 18 (24) ◽  
pp. 1410
Author(s):  
Nisa Pakvilai

The objective of this research was to analyze the potential of biogas production with co-digestion between food waste and cow dung. The experiment research was batched with small scale and scale up with semi-continuous, temperature was operated within 35 - 37 °C. The suitable condition for biogas production between food waste and cow dung was presented with 75:25 (T1). 55 mL of the biogas potential was obtained which is considered as small scale. Thus, the scale up was presented in 75:25 (T1) ratio. In term of scale up the biogas obtained from the production is 650 ml which is higher than small scale. The scale up reactor of biogas production was 100 liters. Chemical oxygen demand (COD) was reduced from 30,000 to 5,000 - 7,000 mL L-1. The efficiency of COD was obtained 76.67 - 83.3 %, respectively. In term of total solid, it was decreased from 19,000 to 16,500 mL L-1. Initial VFA was presented 4,000 mL L-1, and final was presented 3,800 mL L-1, respectively. However, the biogas production from food waste and cow dung can enhance the performance of municipal solid waste and alternative energy production. Finally, the finding of co-digestion in biogas production system suggested utilization in household and communities. HIGHLIGHTS Food waste is the major waste in household, and it has high potential for energy production Co-digestion in biogas production system that suggested utilization in household and communities The biogas production from food waste and cow dung can enhance the performance of municipal solid waste and alternative energy production GRAPHICAL ABSTRACT


2020 ◽  
pp. 140-148
Author(s):  
Md. Kumail Naqvi ◽  
Mrinal Anthwal ◽  
Ravindra Kumar

Biogas is the product of anaerobic vitiation of biodegradable matter. This paper focuses on the need of alternative and green sources of energy at a household level and how biogas produced from the everyday organic waste has the potential and possibility to replace LPG cylinders at houses, shops etc. and empower us to step towards an eco-friendly future. The purpose this small-scale experiment has been to find the perfect input matter that is easy to acquire and which produces the maximum amount of gas from minimum input and within small period of waste retention. Four different types of input waste material containing different quantities of cow dung and kitchen food waste were studied through individual experimental setups. Waste was mixed and kept at room temperature and the pH and total solid concentration of the samples were recorded on regular intervals. From the experiment it was found that the optimum yield of biogas at a small scale, based on the parameters such as retention period, pH and total solid con-centration can be obtained by the use of food waste form households and kitchens. The exact composition has been discussed in this paper. The energy generated by the small-scale generator has also been compared to that of an LPG cylinder and an LPG replacement model has also been presented.


Author(s):  
Prabhat Kumar Sahoo ◽  
Neha S.L ◽  
Arzoo Pannu

Lipids are used as vehicles for the preparation of various formulations prescribed for administrations, including emulsions, ointments, suspension, tablets, and suppositories. The first parental nano-emulsion was discovered from the 1950s when it was added to the intravenous administration of lipid and lipid-soluble substances. Lipid-based drug delivery systems are important nowadays. Solid nanoparticles (SLN) and Nanostructured lipid carriers (NLC) are very proficient due to the ease of production process, scale-up capability, bio-compatibility, the biodegradability of formulation components and other specific features of the proposed route. The administration or nature of the materials must be loaded into these delivery systems. The main objectives of this review are to discuss an overview of second-generation nanoparticles, their limitations, structures, and route of administration, with emphasis on the effectiveness of such formulations. NLC is the second generation of lipid nanoparticles having a structure like nanoemulsion. The first generation of nanoparticles was SLN. The difference between both of them is at its core. Both of them are a colloidal carrier in submicron size in the range of 40-1000 nm. NLC is the most promising novel drug delivery system over the SLN due to solving the problem of drug loading and drug crystallinity. Solid and liquid lipids combination in NLC formation, improve its quality as compare to SLN. NLC has three types of structures: random, amorphous, and multiple. The random structure containing solid-liquid lipids and consisting crystal and the liquid lipid irregular in shape; thereby enhance the ability of the lipid layer to pass through the membrane. The second is the amorphous structure. It is less crystalline in nature and can prevent the leakage of the loaded drug. The third type is multiple structures, which have higher liquid lipid concentrations than other types. The excipients used to form the NLC are bio-compatible, biodegradable and non-irritating, most of which can be detected using GRAS. NLC is a promising delivery system to deliver the drug through pulmonary, ocular, CNS, and oral route of administration. Various methods of preparation and composition of NLC influence its stability Parameters. In recent years at the educational level, the potential of NLC as a delivery mechanism targeting various organs has been investigated in detail.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Gert Vanmarcke ◽  
Mekonnen M. Demeke ◽  
Maria R. Foulquié-Moreno ◽  
Johan M. Thevelein

Abstract Background Presence of inhibitory chemicals in lignocellulose hydrolysates is a major hurdle for production of second-generation bioethanol. Especially cheaper pre-treatment methods that ensure an economical viable production process generate high levels of these inhibitory chemicals. The effect of several of these inhibitors has been extensively studied with non-xylose-fermenting laboratory strains, in synthetic media, and usually as single inhibitors, or with inhibitor concentrations much higher than those found in lignocellulose hydrolysates. However, the relevance of individual inhibitors in inhibitor-rich lignocellulose hydrolysates has remained unclear. Results The relative importance for inhibition of ethanol fermentation by two industrial second-generation yeast strains in five lignocellulose hydrolysates, from bagasse, corn cobs and spruce, has now been investigated by spiking higher concentrations of each compound in a concentration range relevant for industrial hydrolysates. The strongest inhibition was observed with industrially relevant concentrations of furfural causing partial inhibition of both D-glucose and D-xylose consumption. Addition of 3 or 6 g/L furfural strongly reduced the ethanol titer obtained with strain MD4 in all hydrolysates evaluated, in a range of 34 to 51% and of 77 to 86%, respectively. This was followed by 5-hydroxymethylfurfural, acetic acid and formic acid, for which in general, industrially relevant concentrations caused partial inhibition of D-xylose fermentation. On the other hand, spiking with levulinic acid, 4-hydroxybenzaldehyde, 4-hydroxybenzoic acid or vanillin caused little inhibition compared to unspiked hydrolysate. The further evolved MD4 strain generally showed superior performance compared to the previously developed strain GSE16-T18. Conclusion The results highlight the importance of individual inhibitor evaluation in a medium containing a genuine mix of inhibitors as well as the ethanol that is produced by the fermentation. They also highlight the potential of increasing yeast inhibitor tolerance for improving industrial process economics.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 802
Author(s):  
Suye Li ◽  
Hengqian Wu ◽  
Yanna Zhao ◽  
Ruiyan Zhang ◽  
Zhengping Wang ◽  
...  

The quality control of drug products during manufacturing processes is important, particularly the presence of different polymorphic forms in active pharmaceutical ingredients (APIs) during production, which could affect the performance of the formulated products. The objective of this study was to investigate the phase transformation of fexofenadine hydrochloride (FXD) and its influence on the quality and performance of the drug. Water addition was key controlling factor for the polymorphic conversion from Form I to Form II (hydrate) during the wet granulation process of FXD. Water-induced phase transformation of FXD was studied and quantified with XRD and thermal analysis. When FXD was mixed with water, it rapidly converted to Form II, while the conversion is retarded when FXD is formulated with excipients. In addition, the conversion was totally inhibited when the water content was <15% w/w. The relationship between phase transformation and water content was studied at the small scale, and it was also applicable for the scale-up during wet granulation. The effect of phase transition on the FXD tablet performance was investigated by evaluating granule characterization and dissolution behavior. It was shown that, during the transition, the dissolved FXD acted as a binder to improve the properties of granules, such as density and flowability. However, if the water was over added, it can lead to the incomplete release of the FXD during dissolution. In order to balance the quality attributes and the dissolution of granules, the phase transition of FXD and the water amount added should be controlled during wet granulation.


1955 ◽  
Vol 1 (5) ◽  
pp. 299-311 ◽  
Author(s):  
R. Steel ◽  
C. P. Lentz ◽  
S. M. Martin

Factors affecting the production of citric acid in the submerged fermentation of ferrocyanide-treated beet molasses by Aspergillus niger were studied in 2.5 and 36 liter fermenters. The small fermenters were used to determine the effects of changes in sterilization technique, phosphate supplement, ferrocyanide treatment, inoculum level, initial pH, fermentation temperature, and aeration rate. The relation between ferrocyanide concentration and inoculum level was also studied. Four different samples of molasses were fermented successfully. An average yield of 8.2% citric acid (64% conversion) was obtained from 51 small-scale fermentations. Comparable yields were obtained in the large fermenters under comparable conditions. Most of the information obtained with the small fermenters was applicable to the larger-scale fermenters, but in the latter the fermentation was significantly more stable. Aeration was the main problem in the scale-up and aeration rates approximately double those calculated on a fermenter cross-sectional area basis were required for comparable results in the large fermenters.


2013 ◽  
Vol 275-277 ◽  
pp. 1662-1665 ◽  
Author(s):  
Qiang Li ◽  
Juan Juan Fei ◽  
Xu Ding Gu ◽  
Geng Sheng Ji ◽  
Yang Liu ◽  
...  

This study aims to establish a natural cellulosic biomass pretreatment process using ionic liquid (IL) for efficient enzymatic hydrolysis and second generation bioethanol. The IL 1-Butyl-3-methylimidazolium Chloride/FeCl3 ([Bmim]Cl/FeCl3) was selected in view of its low temperature pretreatment ability and the potential of accelerating enzymatic hydrolysis, and it could be recyclable. The yield of reducing sugars from sugarcane residue pretreated with this IL at 80 oC for 1 h reached 46.8% after being enzymatically hydrolyzed for 24 h. Sugarcane residue regenerated were hydrolyzed more easily than that treated with water. The fermentability of the hydrolyzates, obtained after enzymatic saccharification of the regenerated sugarcane residue, was transformed into bioethanol using Candida shehatae. This microbe could absorb glucose and xylose efficiently, and the ethanol production was 0.38 g/g glucose within 30 h fermentation. In conclusion, the metal ionic liquid pretreatment in low temperature shows promise as pretreatment solvent for natural biomass.


Sign in / Sign up

Export Citation Format

Share Document