Effect of structural changes of lignocelluloses material upon pre-treatment using green solvents

The Malaysia Biomass strategy 2020 stated that the key step of biofuel production from biomass lies on the pretreatment process. Conventional ‘pre-treatment’ methods are ‘non-green” and costly. The recent green and cost-effective biomass pretreatment is using new generation of Ionic Liquids also known as Deep Eutectic Solvents (DESs). DESs are made of renewable components are cheaper, greener and the process synthesis are easier. Thus, the present paper concerns with the preparation of various combination of DES and to study the effect of DESs pretreatment process on microcrystalline cellulose (MCC), a model substrate. The crystalline structural changes were studied using using X-ray Diffraction Methods, Fourier Transformed Infrared Spectroscopy (FTIR) and surface area and pore size analysis. Results showed reduction of crystalline structure of MCC treated with the DESs and increment of surface area and pore size of MCC after pre-treatment process. These results indicated the DES has successfully converted the lignocelluloses material in the form suitable for hydrolysis and conversion to simple sugar

Deep eutectic solvents-halophilic cellulase system: An efficient route for in situ saccharification of lignocellulose

Pre-treatment of lignocellulosic biomass is essential for the cost-effective saccharification process to produce fermentable sugars. In this study, Deep Eutectic Solvents (DESs) and halophilic cellulase system were used as a new green and cost-effective approach for lignocellulose hydrolysis. The stability and compatibility between DES and halophilic cellulase for lignocellulose hydrolysis were investigated by monitoring the stability of halophilic cellulase in the occurrence of different concentrations of DESs. It was found that halophilic cellulase showed higher stability in the occurrence of 10–20% (v/v) DES. It has been noticed that 20% of DESs, enhanced 2–3 folds in the release of glucose. The compatibility of the DES-halophilic cellulase system has been further evaluated and improved the saccharification efficiency even at high solid loadings. Using the system , saccharification of the rice husk produced three folds of glucose higher than the untreated sample. The yield was estimated to be higher than 1 mM of glucose using the halophilic cellulase -DES system with the hydrolysis for 36 h. DESs-halophilic cellulase system offers a good alternative compared to the available lignocelluloses pre-treatment method in terms of cost, environmental an

Improvement of halophilic cellulase production from locally isolated fungal strain

Halophilic cellulases from the newly isolated fungus, Aspergillus terreus UniMAP AA-6 were found to be useful for in situ saccharification of ionic liquids treated lignocelluloses. Efforts have been taken to improve the enzyme production through statistical optimization approach namely Plackett–Burman design and the Face Centered Central Composite Design (FCCCD). Plackett–Burman experimental design was used to screen the medium components and process conditions. It was found that carboxymethylcellulose (CMC), FeSO4Æ7H2O, NaCl, MgSO4Æ7H2O, peptone, agitation speed and inoculum size significantly influence the production of halophilic cellulase. On the other hand, KH2PO4, KOH, yeast extract and temperature had a negative effect on enzyme production. Further optimization through FCCCD revealed that the optimization approach improved halophilic cellulase production from 0.029 U/ml to 0.0625 U/ml, which was approximately 2.2-times greater than before optimization

Applicability evaluation of deep eutectic solvents–cellulase system for lignocellulose hydrolysis

Deep Eutectic Solvents (DESs) have recently emerged as a new generation of ionic liquids for lignocellulose pretreatment. However, DESs contain salt components which tend to inactivate cellulase in the subsequent saccharification process. To alleviate this problem, it is necessary to evaluate the applicability of the DESs–Cellulase system. This was accomplished in the present study by first studying the stability of cellulase in the presence of selected DESs followed by applicability evaluation based on glucose production, energy consumption and kinetic performance. Results showed that the cellulase was able to retain more than 90% of its original activity in the presence of 10% (v/v) for glycerol based DES (GLY) and ethylene glycol based DES (EG). Furthermore, both DESs system exhibited higher glucose percentage enhancement and lower energy consumption as compared to diluted alkali system. Among the two DESs studied, EG showed comparatively better kinetic performance

Identification of Trihalomethanes (THMs) Levels in Water Supply: A Case Study in Perlis, Malaysia

In Malaysia, chlorination is used for drinking water disinfection at water treatment plants due to its cost-effectiveness and efficiency. However, the use of chlorine poses potential health risks due to the formation of disinfection by-products such as trihalomethanes (THMs). THMs are formed due to the reaction between chlorine and some natural organic matter. The objective of the study is to analyze the level of THMs in the water supply in Perlis, Malaysia. The water samples were collected from end-user tap water near the water treatment plant (WTP) located in Perlis, including Timah Tasoh WTP, Kampung Sungai Baru WTP, Arau Phase I, II, III, and IV WTPs. The THMs were analyzed using a Gas Chromatography-Mass Spectrometry (GC/MS). The results showed that the water supply from Timah Tasoh WTP generates the most THMs, whereas Kuala Sungai Baru shows the fewest amounts of total THMs. In conclusion, the presence of THMs in tap water has caused great concern since these components can cause cancer in humans. Therefore, the identification of THM formation is crucial in order to make sure that the tap water quality remains at acceptable safety levels

Rubber Tire Recycling and Disposal

Waste management is an important indicator for creating sustainable and livable cities, but it remains a challenge for many countries around the world. Millions of rubber tire waste pollute the environment due to improper disposal methods, creating a global environmental crisis. The number of rubber tire waste piles continues to grow, posing greater environmental, safety, and aesthetic issues due to a lack of clear disposal options. This chapter gives a general overview of rubber tire waste recycling and disposal worldwide. A brief history of natural and synthetic rubber and global rubber production and consumption was first discussed. Next, various rubber tire recycling and disposal technologies were elaborated. This is followed by discussing the issues involved in recycling and disposal

Identification of Trihalomethanes (THMs) Levels in Water Supply: A Case Study in Perlis, Malaysia

In Malaysia, chlorination is used for drinking water disinfection at water treatment plants due to its cost-effectiveness and efficiency. However, the use of chlorine poses potential health risks due to the formation of disinfection by-products such as trihalomethanes (THMs). THMs are formed due to the reaction between chlorine and some natural organic matter. The objective of the study is to analyze the level of THMs in the water supply in Perlis, Malaysia. The water samples were collected from end-user tap water near the water treatment plant (WTP) located in Perlis, including Timah Tasoh WTP, Kampung Sungai Baru WTP, Arau Phase I, II, III, and IV WTPs. The THMs were analyzed using a Gas Chromatography-Mass Spectrometry (GC/MS). The results showed that the water supply from Timah Tasoh WTP generates the most THMs, whereas Kuala Sungai Baru shows the fewest amounts of total THMs. In conclusion, the presence of THMs in tap water has caused great concern since these components can cause cancer in humans. Therefore, the identification of THM formation is crucial in order to make sure that the tap water quality remains at acceptable safety levels

Potential halophilic cellulases for in situ enzymatic saccharification of ionic liquids pretreated lignocelluloses

Ionic liquids (ILs) have been used as an alternative green solvent for lignocelluloses pretreatment. However, being a salt, ILs exhibit an inhibitory effect on cellulases activity, thus making the subsequent saccharification inefficient. The aim of the present study is to produce salt-tolerant cellulases, with the rationale that the enzyme also tolerant to the presence of ILs. The enzyme was produced from a locally isolated halophilic strain and was characterized and assessed for its tolerance to different types of ionic liquids. The results showed that halophilic cellulases produced from Aspergillus terreus UniMAP AA-6 exhibited higher tolerance to ILs and enhanced thermo stability in the presence of high saline conditions

Antifungal activity of essential oil extracted from Melaleuca alternifolia against pathogenic fungi on mangoes (Mangifera Indica L.) for mango postharvest application

Abstract. An infection from pathogenic fungi is one of the main reasons causing the losses of mangoes during postharvesl. An essential oil from Melaleuca alternifolia is being introduced as natural fungicide in controlling postharvest disease of mangoes. The extraction of essential oil from Melaleuca alternifolia was performed using Solvent Free Microwave Assisted Extraction with yield of 0.5% The inhibitory effect of essential oil extracted from . Melaleuca alternifolia against isolated fungi from mango was investigated through in-vitro and in-vivo analysis. Distilled water was used as negative control while chemical fungicide (Globus 5.5) as positive control in the analysis. The mycelial growth inhibition of extracted essential oil for poisoned food test and disc diffusion test showed 62.50 % ±0.49 and 59.70 %± 0.30 respectively for in-vivo experiment which had artificially wounded and unwounded mangoes. The result also demonstrated that the essential oil applied on the wounded mangoes could decrease the disease incidence from l00% to 61.33% for up to 10 days kept at room temperature compared to that of the control. Hence. the essential oil of Melaleuca alternifolia can act as green fungicide and is also a promising alternative to the synthetic chemical fungicide for controlling postharvest disease on mangoes

The antifungal activity of essential oil extracted from Melaleuca alternifolia against pathogenic fungi on mango (Mangifera Indica L.) for mango postharvest application

An infection by pathogenic fungi is one of the major problems in post-harvest stage of mangoes. Therefore, the extraction of essential oil from Melaleuca alternifolia is being tested as a natural fungicide for controlling fungus infections of selected mangoes locally known as susu mango. The extraction was performed using Solvent-Free Microwave Assisted Extraction with a yield of 0.57% concentration. The inhibitory effect of this essential oil against isolated fungi from mango was investigated through in-vitro and in-vivo analyses. Distilled water was used as a negative control while chemical fungicide (Globus 5.5) was used as a positive control in the analyses. The mycelial growth inhibition of the extracted essential oil for poisoned food test and disc diffusion method showed 62.50 +- 0.49% and 59.70 +- 0.30%, respectively, for in-vivo experiment which used unwounded and artificially wounded mangoes. The result also demonstrated that the essential oil applied on the mangoes could decrease the disease incidence from 100% to 61.33% for up to 10 days incubation at room temperature compared to that of the control. Hence, the essential oil of Melaleuca alternifolia can act as a green fungicide and is also a promising alternative to the synthetic chemical fungicide for controlling post-harvest disease on mangoes