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The purpose of this paper is to optimize production of cellulase enzyme from agricultural waste by using Aspergillus fumigatus JCF. The study also aims at the production of bioethanol using cellulase and yeast.

Cellulase production was carried out using modified Mandel’s medium. The optimization of the cellulase production was carried out using Plackett-Burman and Response surface methodology. Bioethanol production was carried out using simultaneous saccharification and fermentation.

Maximum cellulase production at optimized conditions was found to be 2.08 IU/ml. Cellulase was used for the saccharification of three different feed stocks, i.e. sugar cane leaves, corn cob and water hyacinth. Highest amount of reducing sugar was released was 29.1 gm/l from sugarcane leaves. Sugarcane leaves produced maximum bioethanol concentration of 9.43 g/l out of the three substrates studied for bioethanol production.

The present study reveals that by using the agricultural wastes, cellulase production can be economically increased thereby bioethanol production.

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO₂ emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

This study aims to assess the effect of water variation on bioethanol production from cassava peels (CP) using Saccharomyces cerevisiae yeast as the ethanologenic agent.

The milled CP was divided into three treatment groups in a small-scale flask experiment where each 20 g CP was subjected to two-stage hydrolysis. Different amount of water was added to the fermentation process of CP. The fermented samples were collected every 24 h for various analyses.

The results of the fermentation revealed that the highest ethanol productivity and fermentation efficiency was obtained at 17.38 ± 0.30% and 0.139 ± 0.003 gL⁻¹ h⁻¹. The study affirmed that ethanol production was increased for the addition of water up to 35% for the CP hydrolysate process.

The finding of this study demonstrates that S. cerevisiae is the key player in industrial ethanol production among a variety of yeasts that produce ethanol through sugar fermentation. In order to design truly sustainable processes, it should be expanded to include a thorough analysis and the gradual scaling-up of this process to an industrial level.

This paper is an original research work dealing with bioethanol production from CP using S. cerevisiae microbe.

1. Hydrolysis of cassava peels using 13.1 M H₂SO₄ at 100 ^oC for 110 min gave high Glucose productivity

2. Highest ethanol production was obtained at 72 h of fermentation using Saccharomyces cerevisiae

3. Optimal bioethanol concentration and yield were obtained at a hydration level of 35% agitation

4. Highest ethanol productivity and fermentation efficiency were 17.3%, 0.139 g.L⁻¹.h⁻¹

Hydrolysis of cassava peels using 13.1 M H₂SO₄ at 100 ^oC for 110 min gave high Glucose productivity

Highest ethanol production was obtained at 72 h of fermentation using Saccharomyces cerevisiae

Optimal bioethanol concentration and yield were obtained at a hydration level of 35% agitation

Highest ethanol productivity and fermentation efficiency were 17.3%, 0.139 g.L⁻¹.h⁻¹

The objective of this study was to evaluate the influence of Saccharomyces boulardii on the kinetics of fermentation for organic and conventional apple pulp and to verify the effect of the antioxidant quercetin on the response to cellular oxidative stress.

The kinetic parameters, the content of phenolic compounds, the quantity of quercetin and the antioxidant activity were determined during the fermentation process. The effect of quercetin on cellular oxidative stress was also investigated.

The content of phenolic compounds, the antioxidant activity and the quercetin concentration were higher in the organic fermented apple pulp (ORG) than in the conventional fermented apple pulp (CON). However, both apple pulps were considered ideal substrates for the growth of S. boulardii, suggesting that they are potentially probiotic. After fermentation, the quercetin concentration in the ORG treatment and YPDQ treatment (YPD broth with 0.1 mg quercetin rhamnoside/mL) increased viability by 9%, while in the CON treatment generated there was an increase of 6% in viability, compared to the YPD control treatment (YPD broth).

The high concentration of quercetin in the organic apple pulp supports the proposal that quercetin reduces the oxidative stress mediated by reactive oxygen species through its antioxidant action on S. boulardii that have similarities to mammalian eukaryotic cells. These findings suggest that fermented organic apple pulp could be consumed as a potential non-dairy probiotic product.

In 2008, a number of Southern African countries cultivated about 900,000 ha of Jatropha, with a number of biodiesel plants ready for production; however, none of the projects succeeded. In 2014, KiOR advanced biofuel Energy Company in the USA announced bankruptcy due to incompetent technology. Studies disclose that the reasons for biofuel plants failure are not only due to lack of incentives and unclear policies but also due to lack of economic feasibility and low production yields. This paper aims to review the techno-economy assessment of second-generation biofuel technologies. The purpose of this paper is to summarize specific techno-economic indicators such as production cost, technology efficiency and process life cycle analysis for advanced biofuel technology and to narrate and illustrate a clear view of what requires assessment to deploy a feasible advanced biofuel technology. This study also reviews assessment of biomass supply chain, feedstock availability and site selection criteria. The review also elaborates on the use of different processes, forecasting and simulation-modeling tools used in different techno-economic analysis studies. The review provides guidance for conducting a technical and economic feasibility study for the advanced biofuels energy business.

The aim of this review is, therefore, to evaluate the techno-economic feasibility studies for the establishment of viable industrial scale production of second-generation biofuels. It does so by grouping studies based on technology selection, feedstock availability and suitability, process simulation and economies as well as technology environmental impact assessment.

In conclusion, techno-economic analysis tools offer researchers insight in terms of where their research and development should focus, to attain the most significant enhancement for the economics of a technology. The study patterns within the scope of techno-economics of advanced biofuel reveal that there is no generic answer as to which technology would be feasible at a commercial scale. It is therefore important to keep in mind that models can only simplify and give a simulation of reality to a certain extent. Nevertheless, reviewed studies do not reach the same results, but some results are logically similar.

The originality of this article specifically illustrates important technical and economic indicators that should be considered when conducting feasibility studies for advance biofuels.

–Prosopis juliflora is a raw material for long-term sustainable production of bioethanol. The purpose of this paper is to identify the best combination of pre-treatment strategy implemented on the lignocellulosic biomass Prosopis juliflora for bioethanol production.

Pre-treatment of lignocellulosic material was carried out using acid, alkali and sonication in order to characterize the biomass for bioethanol production. Prosopis juliflora stem was subjected to steam at reduce temperature (121°C) for one hour residence time initially. Further acid and alkali treatment was carried out individually followed by combinations of acid and sonication, alkali and sonication. Sodium hydroxide, potassium hydroxide, hydrochloric acid, sulphuric acid and nitric acid were used with 3 per cent (w/v) and 3 per cent (v/v) concentration under temperature range of 60-90°C for 60 min incubation time. Sonication under 60°C for 5 min and 40 KHz frequency was carried out. Pre-treated sample were further characterised using field emission scanning electron microscope and Fourier transform infrared spectroscopy to understand the changes in surface morphology and functional characteristics.

In sono assisted acid treatment-based method, nitric acid yields better cellulose content at 70°C and removes lignin that even at increased temperatures no burning was observed.

The paper adds to the scarce research available on the combination of auto hydrolysis coupled with sono assisted acid/alkali hydrolysis which is yet to be practiced.

The use of ethanol from biomass as a gasoline substitute in cars and light trucks is possibly one of the most attractive and feasible alternatives to deal with global warming. As environmental concern grows, many countries are increasing their efforts to consolidate bioethanol processes and supply. The sustainable production of bioethanol requires well planned and reasoned development programs to assure that the many environmental, social and economic concerns related to its use are addressed adequately. The key for making ethanol competitive as an alternative fuel is the ability to produce it from low‐cost biomass. Many countries around the world are working extensively to develop new technologies for ethanol production from biomass, from which the lignocellulosic materials conversion seem to be the most promising one. This paper aims at providing some information about the status of bioethanol production and use around the world.

The purpose of this study was to evaluate the in vitro and in vivo effects of three varieties of Indonesian fermented rice bran (RB) (Inpari 6, Inpari 30 and Inpara 1).

Three types of RB were fermented using Rhizopus oligosporus. The total phenolic content (TPC) was determined using the Folin–Ciocalteau method, and antioxidant activity was analyzed by measuring the 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (RSA). For in vivo analyses, one week after acclimatization, stroke-prone spontaneously hypertensive rats (n = 4, 12 weeks of age) were divided into two groups and orally administered fermented RB (40 mg/kg body weight) or distilled water as a control after 16 h of fasting. Blood pressure (BP) was measured before and 2, 4 and 6 h after administration with a BP monitor without warming. Six days later, the rats were subject to the same procedure and sacrificed after 6 h of oral administration. Blood was collected and the plasma was separated to measure nitric oxide, glucose and insulin levels.

The highest TPC and RSA of fermented RB were obtained from Inpari 30 after incubation for 72 h (260.33 ± 0.39 mg GAE/100 g dry basis and 83.71 ± 0.61 per cent), respectively. Furthermore, single oral administration of fermented RB improved BP (p < 0.05) and glucose metabolism after 6 h of administration (p < 0.05).

This is the first study to evaluate the effects of fermented RB on improving high BP and glucose profiles by using a spontaneously hypertensive animal model.

The purpose of this study is to investigate the influence of light intensity and sources of carbon and nitrogen on the cultivation of Spirulina maxima.

Cultures were carried out in a modified Zarrouk medium using urea, sodium acetate and glycerol. A Taguchi experimental design was used to evaluate the effect on the production of biocompounds: productivities in biomass, carbohydrates, phycocyanin and biochar were analyzed.

Statistical data analysis revealed that light intensity and sodium acetate concentration were the most important factors, being significant in three of the four response variables studied. The highest productivities in biomass (46.94 mg.L⁻¹.d⁻¹), carbohydrates (6.11 mg.L⁻¹.d⁻¹), phycocyanin (3.62 mg.L⁻¹.d⁻¹) and biochar (22, 48 mg.L⁻¹.d⁻¹) were achieved in experiment 4 of the Taguchi matrix, highlighting as the ideal condition for the production of biomass, carbohydrates and phycocyanin.

Sodium acetate and urea can be considered, respectively, as potential sources of carbon and nitrogen to increase Spirulina maxima productivity. From the results, an optimized cultivation condition for the sustainable production of bioproducts was obtained.

This work focuses on the study of the influence of light intensity and the use of alternative sources of nitrogen and carbon on the growth of Spirulina maxima, as well as on the influence on the productivity of biomass and biocompounds. There are few studies in the literature focused on the phycocyanin production from microalgae, justifying the need to deepen the subject.

Chili pepper pods are a worldwide used and cultivated spice with a high economic and cultural importance. Bolivia is a center of origin and diversification of important crops including wild pepper varieties, but little is known about the chemical composition, antioxidant activity and the Scoville and bioactive compounds of these chili peppers. The purpose of this study was to contribute with new data about the chemical composition and the Scoville scale of Bolivian Chili peppers.

A total of 26 samples of Bolivian Chili peppers were extracted using distilled water and methanol. Total antioxidant capacity was determined by the ferric-reducing antioxidant power (FRAP) and by the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) methods. The total phenolic content was determined by Folin and Ciocalteu. Carotene, protein and ashes were determined by Bolivian analytical norms. Capsaicin was determined by high-performance liquid chromatography. All determinations were expressed as mean values± standard deviation of six replicates measured over three days of one extract. All values were less than 5% of coefficient of variation. Principal component analysis was applied to reveal patterns in the data. PC1 and PC2 together explained 78% of the total variance.

The protein content (3.8–6.3 g/100 g of dw) and the antioxidant activity (88.2 to 374 by FRAP and 87.0 to 172 evaluated by ABTS) studied in these species revealed that the values were above the average reported in the literature. The amount of pungency or capsaicin content expressed as Scoville Heat Units were reported moderately highly and very highly pungent (5,696–148,800 g dw) in several of the Bolivian peppers which demonstrates a good potential for capsaicin extraction and different applications for industry and as food ingredients.

This manuscript presents an important and novel contribution to the knowledge of the chili peppers in the region.