Bioproduction refers to the use of biological systems

Bioproduction refers to the use of biological systems—such as microorganisms, cells, or enzymes—to produce valuable products on an industrial scale. These products can include pharmaceuticals, chemicals, biofuels, food ingredients, and other materials that are essential in various sectors like healthcare, agriculture, and biotechnology.

1. Bioethanol Production

2. Global resource and environmental challenges drive the need for sustainable solutions. Coffee waste, with over 6.5 million tons of spent coffee grounds (SCGs) produced annually, offers potential for bioethanol production due to its fermentable sugars (mannose, glucose, and galactose). Liquid hot water (LHW) pretreatment preserves these sugars and reduces environmental impact, followed by separate hydrolysis and fermentation (SHF) to produce bioethanol. introduction

3. Spent Coffee Grounds (SCGs): Obtained from a Starbucks coffee shop in China. Chemical Analysis: analyze SCG components (cellulose, hemicellulose, lignin) Enzymes: Celluclast , β- mannanase . Yeast: Saccharomyces cerevisiae. Materials

4. Glucose Conversion: Increased with higher temperatures and longer times, peaking at 180 °C for 60 minutes. Mannose Conversion: At 170 °C, conversion remained stable with longer times. At 180 °C, conversion decreased as time extended from 20 to 60 minutes, with optimal conversion at 180 °C for 20 minutes before degradation increased. Pretreatment Temperature and Retention Time

5. Effects of liquid hot water pretreatment temperature and time on enzymatic hydrolysis and fermentation of SCG. table 1

6. The concentration of inhibitors (g/L) in the fermentation broth under different pretreatment conditions. figure 1

7. Optimal Conversions: Highest glucose and mannose conversions at SLR 1:18; conversions decreased with higher solid ratios. Ethanol Yield: Maximum ethanol concentration (15.87 g/L) and productivity at SLR 1:6, reducing water usage by 66.7%. Efficiency: SLR 1:6 balanced high product concentration, productivity, and low inhibitor levels. Fermentation Time: SLR 1:18 to 1:9 completed fermentation in 6 hours; SLR 1:6 took 9–12 hours. Solid-to-Liquid Ratio (SLR)

8. Enzyme Optimization: Mannose conversion peaked at 3000–5000 U/g β- mannase , stabilizing after 36 hours. Best Dosage: A β- mannase dosage of 3000 U/g SCG was optimal for balancing economic benefits and conversion rates. Optimization of Enzymatic Hydrolysis Process

9. Retention: Both glucan and mannan were retained in the liquid and solid fractions, highlighting the benefits of whole-slurry preparation. Enhanced Yields: Ethanol yield from LHW-pretreated SCGs was 71.92 mg/g SCG higher than untreated SCGs. LHW pretreatment boosted total fermentable sugar and ethanol yields by 221.21% and 185.78%, respectively, compared to raw SCGs. Mass Balance

10. Overall mass balances of 100 g SCG for different pretreatment methods under optimal conditions. figure 2