Journal of Chemical Engineering and Industrial Biotechnology

Effect of Process Parameters on Immobilization of Recombinant Escherichia coli on Coconut Fiber

Thu, 20 Jun 2024 00:00:00 +0000

Escherichia coli (E. coli) is the earliest and most widely used host to produce recombinant proteins, one such example being cyclodextrin glucanotransferase (CGTase) which has found application in numerous industries such as food, environmental engineering and pharmaceutical. The recombinant protein in E. coli was applied to overcome the low output of CGTase from Bacillus species such as Bacillus lehensis and Bacillus licheniformis. However, cell lysis and plasmid instability have been some of the stumbling blocks during the production of recombinant protein in E. coli. Therefore, cell immobilization has been proposed as a way to increase CGTase production while maintaining high cell stability. The objective of this study is to immobilize recombinant E. coli on coconut fiber. The effect of the process parameters, namely pH level (5, 6, 7, 8, and 9), contact time (12, 15, 18, 21, 24, and 27 hours), and temperature (20, 25, 30, 35, and 40 °C), towards the immobilization of recombinant E. coli onto coconut fiber was studied. The optimal pH resulted in the highest immobilization yield was pH 8 (58.90%). The best contact time for the highest immobilization yield (57.59%) was 24 hours. The optimum temperature was identified at 25 °C with immobilization yield of 58.78%. Hence, the optimum conditions could improve the immobilization of recombinant E. coli on the carrier and the coconut fibre was an appropriate carrier material for cell immobilization process for the high CGTase production with high cell stability.

Optimization of Starter Bokashi Bran From Expired Mushroom Blocks Using Central Composite Design

Amir Syarifudin Baharudin, Norazwina Zainol — Thu, 20 Jun 2024 00:00:00 +0000

Mushroom production as the largest solid-state fermentation industry globally. It draws attention to a significant economic and environmental challenge, specifically the storage and disposal of expired mushroom blocks (EMBs) remaining after harvest. Importance of ongoing biotechnological research focused on fungi utilizing various agro-industrial wastes to produce biofertilizer for industrial. The paper proposes using EMBs as a substrate for Bokashi fermentation as fertilizer, focusing on the development of starter Bokashi Bran. The study identifies and optimize bacterial and fungal growth in Bokashi Fermentation using ADA starter Bokashi bran sample from ADA Fresh Farm, Johor Bharu using Response Surface Methodology (RSM). Factors affecting growth both microbes were analysed: EMB content (2 g/ml to 10 g/ml) and fermentation durations (5 days to 9 days). The analysis analysed the highest bacterial and fungal growth in Starter Bokashi Bran using the Design Experts (DE) software Version 7.0 predicting maximum growth at 8 days and 4g/ml respectively. The quadratic model showed a good fit, with an R-squared value exceeding 0.80 and a confidence level surpassing 95%.The research demonstrated that EMBs can be utilized as alternative medium for starter bokashi bran that are eco-friendly and sustainable biofertilizer.

Variation of Nanocellulose Reinforced Recycled Paper: Effect on Tensile Strength

Thu, 20 Jun 2024 00:00:00 +0000

The idea of paper recycling was done due to environmental issue. However, the properties of recycled paper like tensile will decrease each time it is recycled. Addition of reinforcing filler may increase the properties of recycled paper. Thus, in this research, nanocellulose was used as reinforcing filler in recycled paper. The objectives of this research are to fabricate papers from recycled paper and to investigate the effect of different nanocellulose and pressure of compression molding in paper fabrication towards tensile strength of recycled paper. Two types of nanocellulose used were commercialized cellulose nanofiber (CNF) and cellulose nanocrystals (CNC). CNC from filter paper and empty fruit bunches (EFB) were isolated via acid hydrolysis. The recycled paper was fabricated using traditional me. thods (net) and further processed with compression molding. All samples with nanocellulose increase in tensile strength. The tensile strength recorded 114% improvement at 15.28 N/mm² with 5wt% of CNF.

Parametric Screening of Fermentation Conditions for Protease Production from Pineapple Waste

Thu, 20 Jun 2024 00:00:00 +0000

Pineapple waste is abundant in cellulose, hemicellulose, lignin, complex carbohydrates, and protein. One simple way to use pineapple waste as a substrate is to utilize it with the probiotic beverage to produce enzymes through submerged fermentation. Studies on fermentation using pineapple waste have mainly focused on cellulose, xylanase, and pectinase, with little information on protease fermentation. Future studies on pineapple waste-based protease fermentation should be conducted. The present work aims to investigate the significant process parameters affecting protease fermentation from pineapple waste. The parametric screening was performed using the two-level fractional factorial design by Design Expert 7.1.6. In this work, four process parameters were manipulated for protease fermentation which is incubation time from 24 hours to 72 hours, temperature from 20.0 °C to 40.0 °C, substrate concentration from 10.0 % to 30.0 % and pH value from 4.0 to 8.0. The result showed that the most significant process parameters affecting protease fermentation were temperature, pH value and incubation time. This study investigated that the highest protease activity, 0.118 U/mL can be obtained with 48 hours of incubation time, 30.0 °C of temperature, 20.0 % of substrate concentration and pH 6.0.

Sustainable Materials in Concrete Railway Sleepers: A Review of Current Developments and Future Prospects

Jia Jun Yee, Sheh Ching Khong, JiaLing Che, Kong Fah Tee, Siew Choo Chin — Thu, 20 Jun 2024 00:00:00 +0000

Concretes have been the favoured material to make concrete railway sleepers due to better accessibility and weather compared to their timber counterparts. Railway sleepers are crucial infrastructure and 5% of concrete sleepers fail prematurely. Sleeper failure could result in catastrophic railway accidents. Hence, improvement is needed in the concrete sleeper mixes. Previous literature has identified two methods of improving concrete strength in concrete mixes with wastes, through replacement of concrete constituents or the use of alkali-activated materials. Use of wastes as partial concrete material replacements reduces the volume of concrete materials while alkali-activated material forms a concrete-like compound that eliminates the use of cement. These methods improve the strength performance and sustainability aspects of the concrete. While many studies have been conducted on these two types of sustainable concrete, their application in concrete railway sleepers has not been investigated. Thus, this paper looks to review the two different types of sustainable concretes through some previous literature that has been conducted on its application in concrete railway sleepers as well as those that have yet to be studied. Ultimately, identifying the best sustainable materials for concrete railway sleepers.