Now showing 1 - 6 of 6
  • Publication
    A Bio-Inspired herbal tea flavour assessment technique
    Herbal-based products are becoming a widespread production trend among manufacturers for the domestic and international markets. As the production increases to meet the market demand, it is very crucial for the manufacturer to ensure that their products have met specific criteria and fulfil the intended quality determined by the quality controller. One famous herbal-based product is herbal tea. This paper investigates bio-inspired flavour assessments in a data fusion framework involving an e-nose and e-tongue. The objectives are to attain good classification of different types and brands of herbal tea, classification of different flavour masking effects and finally classification of different concentrations of herbal tea. Two data fusion levels were employed in this research, low level data fusion and intermediate level data fusion. Four classification approaches; LDA, SVM, KNN and PNN were examined in search of the best classifier to achieve the research objectives. In order to evaluate the classifiers' performance, an error estimator based on k-fold cross validation and leave-one-out were applied. Classification based on GC-MS TIC data was also included as a comparison to the classification performance using fusion approaches. Generally, KNN outperformed the other classification techniques for the three flavour assessments in the low level data fusion and intermediate level data fusion. However, the classification results based on GC-MS TIC data are varied.
      32  3
  • Publication
    Deep Eutectic Solvent Pretreatment of Rubber Seed Shells for Cellulose and Hemicellulose Production
    ( 2023) ;
    Norshakilla Afendi
    ;
    ;
    Younesi Habibollah
    ;
    Ethanol is a clean biofuel that can be produced from biomass, namely, rubber seed shells. Rubber seed shells (RSS) tend to be less worthy and are rapidly becoming an agricultural waste. The environment is getting incredibly degraded as the industrial world constantly expands and has become more technologically developed in industrial operations. Generally, the most common chemical method used in pretreatment is acid and alkaline based. However, this method is unsuitable since it causes a lot of problems such as inhibitors generation and high energy consumption during the pretreatment process. Therefore, in this study, deep eutectic solvent (DESs) was used as the green solvent to pretreat the RSS for more environmentally friendly production of cellulose and hemicellulose. Seven combinations of hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD) were used to synthesize DESs based on their molar ratio and physiochemical properties (pH, viscosity, density, hydrogen bond) were examined. Later, the best synthesized DES to pretreat RSS based on the cellulose and hemicellulose content was evaluated. The chemical composition (cellulose, hemicellulose and lignin) for untreated and pretreated RSS were determined by using the ASTM and TAPPI methods. The experimental results showed that the higher cellulose production were obtained by using acidic based DESs; ChCl:Oxalic acid, ChCl:Lactic acid and ChCl:Formic acid (24.43, 20.42, and 20.31%, respectively). Meanwhile, higher hemicellulose was obtained when using ChCl:Ethylene glycol and ChCl:Urea, with 46.86% and 41.14%, respectively. Hence, the study showed that acidic and slightly acidic based DESs were able to produce high cellulose and hemicellulose from RSS.
      17  3
  • Publication
    Utilization of Gracilaria sp. liquid for bioethanol production
    Seaweed liquid from filter-pressed drying process of Gracilaria sp. has caused unpleasant odour to the environment. Although this liquid can partially be used as biofertilizer and heavy metals adsorbent, a bigger portion of the liquid remain unutilized thus causing problem to environment. The present study was aimed at utilizing Gracilaria sp. liquid either as ethanol feedstock or supplement in fermentation media. To achieve this aim, Saccharomyces cerevisiae was used as a benchmark. Some locally isolated strains have been screened, isolated and tested their efficacy in fermenting Gracilaria sp. liquid to produce ethanol. Prior to fermentation, the liquid was pretreated using thermal dilute sulphuric acid hydrolysis in sequence to increase reducing sugar concentration and its conditions were statistically optimized by using Response Surface Methodology (RSM) method. The optimum condition of thermal dilute acid hydrolysis obtained was 0.3 M sulphuric acid, 0.7 g/ml of substrate and 120 oC. Nevertheless, all the potential strains isolated in this study produced lower yield as compared to S.cerevisiae. Therefore, this yeast was used in subsequent experiments. However, when used as a supplement in the fermentation media to produce ethanol using S.cerevisiae, the liquid was able to boost the ethanol production three folds from 200 mg/L of 2 % glucose alone to 600 mg/L of 2% glucose in the liquid. Additionally, the Gracilaria sp. liquid was able to substitute yeast extract and peptone within Yeast Potato Dextrose (YPD) media to produce 647.48 mg/l ethanol as compared to only 542.39 mg/l with normal YPD which contains yeast extract and peptone. For that reason, utilization of Gracilaria sp. liquid as the supplement in the medium should be considered because it is capable to enhance ethanol production without addition of other nutrients.
      1  36
  • Publication
    Evaluation of various lignocellulosic biomass and cereal grains as potential spawn materials for wild Schizophyllum commune cultivation
    Rapid mycelium growth in spawn production and on growth substrate could suppress contamination, which is significant in mushroom industry. The aim of the study is to investigate the potential of lignocellulosic biomass waste as new materials alternative to common cereal grains in producing spawn for wild S. commune cultivation on rice husk, paddy straw, and rubber wood sawdust. The fastest mycelium growth among lignocellulosic biomass was found on rice husk spawn (1.27 cm/day) and 1.98 cm/day for wheat grain. The shortest duration for substrate colonization for both lignocellulosic and grain spawn is on paddy straw, followed by rice husk, and rubber wood sawdust.
      3  40
  • Publication
    OPTIMIZATION OF DIFFERENT PARAMETERS IN THE SYNTHESIS OF BISPHENOL A IMPRINTED POLYMER VIA PRECIPITATION POLYMERIZATION FOR BISPHENOL A ADSORPTION
    Molecularly imprinted polymer (MIP) is used to synthesize receptors and is highly recognized against target molecules. The purpose of the study is to prepare bisphenol A (BPA) imprinted polymer that can be used to adsorb BPA molecules. The MIP was prepared by precipitation polymerization using BPA as a template, methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EGDMA) as a crosslinker, acetonitrile as a solvent, and 1,1'-azobis(cyclohexanecarbonitrile) (AIBN) as an initiator by heating in an oil bath at 60 °C for 20 hours. The influence of several parameters (i.e., the ratio of monomer-template, the amount of crosslinker, and the amount of solvent) on the recognition capability of BPA MIP was investigated using response surface methodology (RSM). The optimal conditions of BPA synthesis are 3 mmol of monomer, 30 mmol of crosslinker, and 35 mL of solvent, which achieved an adsorption capacity of 78.111 mg/g. The MIP and non-imprinted polymer (NIP) were characterized using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The MIP shows higher selectivity towards BPA compared to other analogs. In conclusion, the particles of imprinted polymer have a great potential in the adsorption of BPA.
      10  31
  • Publication
    Utilization of Seaweed (Gracilaria sp.) Liquid as Cost-Effective Macronutrients and Micronutrients for Bioethanol Production
    Seaweed liquid waste from filter-squeezed drying process of Gracilaria sp. causes an unpleasant odour to the environment. Although this waste can partially be used as biofertilizer and heavy metals adsorbent, a bigger portion of the waste remains unutilized thus causing a problem to the environment. The present study aimed to utilize seaweed liquid waste as a supplement in fermentation media. To achieve this aim, Saccharomyces cerevisiae as a famous bioethanol producer was used to examine the ability of seaweed liquid to supply macronutrients and micronutrients in the media to produce ethanol. Interestingly, when used as a supplement in the fermentation media to produce ethanol, the liquid boosted ethanol production three folds from 200 mg/L of 2 % glucose alone to 600 mg/L of 2 % glucose in liquid. Additionally, the liquid was able to substitute yeast extract and peptone within YPD media to produce 647.48 mg/L ethanol as compared to only 542.39 mg/L with normal YPD which contains yeast extract and peptone. For that reason, the utilization of seaweed liquid as the supplement in the medium should be considered as an alternative cost-effective media for enhancing ethanol production without the addition of other nutrients.
      26  4