Now showing 1 - 10 of 43
  • Publication
    Utilization of Seaweed (Gracilaria sp.) Liquid as Cost-Effective Macronutrients and Micronutrients for Bioethanol Production
    ( 2023-01-01)
    Zakaria N.Z.I.
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    Dzahir M.I.H.M.
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    Ahmad A.A.
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    Ismail K.S.K.
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    Mahmod S.S.
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    Javed M.
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    B.-Yazdi N.
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    Saifuddin M.N.A.A.
    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.
  • Publication
    Exploring antioxidant and antidiabetic potential of Mutingia calabura (Kerukupsiam) leaf extract: In vitro analysis and molecular docking study
    ( 2024-01-01) ;
    Prammakumar N.K.
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    Ahmad A.A.
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    Bakar A.R.A.
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    Musa H.
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    Antioxidant activity and antihyperglycemic constituents and of traditional medicinal plants are currently the preferred therapeutic means of treatment and management of diabetes because of the undesired adverse effect of synthetic drugs. Muntingia calabura (Kerukupsiam) leaves and other parts are considered as alternative natural sources of treatment for diabetes. Ultrasonic assisted extraction is a novel approach for extraction of phytoconstituents which gives high extraction yield of bioactive compounds. However, there has been no published information presently on the use of ethanol ultrasonic assisted extraction method for assessment of antioxidant and antidiabetic activities of M. calabura leaves. Hence, the current study aims to evaluate the in vitro antioxidant and antidiabetic activities of M. calabura leave extract. IC50 analysis was done to determine theinhibitory concentration and the results obtained from 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay showed IC50 of gallic acid to be 1.0 µg/ml, which is lower than M. calabura leaves extract at 2.54 µg/ml, indicating that only small concentration of gallic acid was required to inhibit the free radicals at 50 %. However, IC50 analysis for amylase inhibition showed that M. calabura extract had 44.39 µg/ml antidiabetic activity compared to acarbose with 57.1 µg/ml activity. This indicates that M. calabura leaves extract has a better inhibition on amylase activity compared to the acarbose which is a synthetic drug. Further still, in silico study was carried out and the molecular docking result of eight ligands against amylase indicates quercetin had the least binding free energy of −9.1 kcal/mol, indicating the strongest interaction. Using Lineweaver-Burk plot, the results showed a competitive inhibition, hence, it was justified that M. calabura has the potential to manage diabetes and other diseases related to free radicals.
  • Publication
    Fabrication of active food packaging based on PLA/Chitosan/CNC-containing Coleus aromaticus essential oil: application to Harumanis mango
    ( 2023-12-01)
    Hasnida Raja Hashim R.
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    Fong Y.Y.
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    Pareek S.
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    Makhtar M.M.Z.
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    This study aimed to determine the effect of Coleus aromaticus essential oil (CAEO) on the properties of an active film based on polylactic acid (PLA), chitosan (Cs), and cellulose nanocrystal (CNC) in fruit packaging. The films were fabricated via solvent casting technique. The obtained films’ antimicrobial, antioxidant, microstructural, and mechanical properties were studied. Mechanical properties state how adding essentials oil into film improves the elongation breaks significantly (p < 0.05) by 5.3 and 6.1%, respectively, with the addition of 0.4 wt% and 0.8 wt% CAEO which reflets its flexibility. The antioxidant activity of biopolymer film increased significantly (p < 0.05), with antioxidant values ranging from 6.50 to 57.50% with the elevation of CAEO. The inhibitory impact of the film against pathogenic fungus was evaluated in vitro and in vivo by comparing the film with different concentrations of essential oil (EO), as well as the control and chemical fungicide. Disc diffusion was utilised to test mycelial growth suppression, and the film containing 1.2 wt% EO produced the best results. The biofilm containing 1.2 wt% EO successfully reduced illness incidence in vivo with damaged mango. Scanning Electron Microscopy and Transmission Electron Microscopy imaging were used to observe the incorporation of CAEO in the matrix of the film. All Fourier-Transform Infrared spectra of PLA/Cs/CNC and EO blends exhibited the characteristic bands of PLA-based materials. The results indicate that the PLA/Cs/CNC/CAEO films provide a new way to improve microbial safety and extend the shelf life of mango fruit and have the potential for replacement of petroleum-based plastic for fruit packaging applications at the industrial level.
  • Publication
    Antifungal Activity of Essential Oil Extracted from Melaleuca alternifolia Against Pathogenic Fungi on Mango (Mangifera Indica L.) for Mango Postharvest Application
    ( 2022-01-01) ;
    Seminai J.J.A.
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    Ahmad A.A.
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    Yusof R.
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    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.
  • Publication
    Generation of Microcrystalline Cellulose from Cotton Waste and its Properties
    ( 2023-01-01)
    Tan W.Y.
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    Anbu P.
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    Velusamy P.
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    Chen Y.
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    Subramaniam S.
    Microcrystalline cellulose (MCC) is a green material that has widespread applications in pharmaceuticals, food, cosmetics, and other industries because of its biocompatibility, biodegradability, hydrophilicity, and acid-insolubility. In this study, MCC was prepared from cotton waste via alkaline treatment and sulfuric acid hydrolysis. Further, the synthesized cotton-based MCC was characterized using Fourier transform infrared (FTIR), X-ray photoelectron, and energy dispersive X-ray spectroscopies. Based on these results, the major components were identified as carbon and oxygen. This finding was evidenced by the FTIR analysis, which displayed peak wavenumbers at 3446.9, 2891.1, 1649.5, 1380.1, 1061.2, and 1050 to 1150 cm-1. The surface morphology was also examined by field emission scanning electron microscopy and field emission transmission electron microscopy, which showed that the prepared MCC has a smooth surface and a consistent, rod-like shape. In addition, the MCC exhibited the typical diffraction peaks of a crystalline structure of cellulose II at 12.2°, 20°, and 22.03°, which correspond to the diffraction planes of 1-10, 110, and 020, respectively, and had a crystallinity index of 78.7%. Moreover, the prepared MCC had a diameter of 37.8 µm and exhibited good stability with a peak at-76.5 mV. Further, the cotton-based MCC exhibited high thermal stability, as revealed by the TGA.
  • Publication
    Bio-based Packaging Materials for Fruit and Vegetables-Current Applications and Future Trends: A Review
    A growing concern of green packaging material for fresh fruit and vegetables is highly demanded. Deterioration of fresh fruits and vegetables primary causes by postharvest damage, moisture loss, biochemical changes, and microorganism. To achieve this goal, biopolymers should be economic, renewable, abundant, and capable of preserving microbial growth while having an outstanding thermal, mechanical, and barrier properties. The most current developments in biopolymer-based coatings and films for active fruit and vegetables packaging are described in this review. Synthetic polymers from biomass monomers (PHA and PLA), animal derived biopolymer (chitosan, gelatin, whey protein, casein and others) and wood-based polymers (cellulose, hemicellulose, starch, lignin and others) were among the materials that were most widely exploited for the packaging development of coatings and films. Reinforcement with nanomaterials and incorporating active agents such as antimicrobial, organic (e.g. nanocellulose fibrils), and inorganic materials also address these shortcomings in biopolymer-based composite This review summarized the characteristics and advantages of whole or fresh cut fruit and vegetables bio-based packaging, as well as the methods employed to improve their performance.
  • Publication
    Determination of degree of acetylation (DA) for chitin in deep eutectic solvents (DES)
    Degree of acetylation (DA) is an important parameter to determine the quality of chitin. Apart from the assessment on the bond structure in the chitin molecule, infrared spectroscopy is one of the methods that can be used to determine the value of DA. The DA value of chitin is an important parameter because the value indicates the purity of chitin quality. Chitin acetylation is the process of addition an acetyl substitution group (-COCH3) to a chitin chain. The addition of acetyl will improve its dispersing properties and subsequently will improve the chitin adhesion properties within hydrophobic matrix in composite materials as well. In this study, Deep Eutectic Solvent (DES) was used as a medium for chitin extraction and acetylation in one single process. DES has two components namely Hydrogen Bond Donor (HBD) and Hydrogen Bond Acceptor (HBA). Betaine and choline chloride were used as HBA whilst urea was selected to be utilized as HBD. The findings showed that the quantity of extracted chitins by the DESs were 5.4609 % and 2.0020 % respectively. The DA values for the extracted chitins are 103.1699 and 83.4821. For acetylated chitin in DES betaine - urea, the DA value was increased from 103.1699 to 118.4818. The findings showed that the high quality acetylated chitin can be produced in a single process involving extraction and acetylation process by using DES as a medium.
  • Publication
    The Use of Essential Oil Embedded in Polylactic Acid/Chitosan-Based Film for Mango Post-Harvest Application against Pathogenic Fungi
    ( 2023-06-01) ;
    Leem S.J.
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    Makhtar M.M.Z.
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    Zainuddin N.
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    Mohd Roslim M.H.
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    Raja Hashim R.H.
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    Pusphanathan K.
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    Siddiqui M.R.
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    Alam M.
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    Rafatullah M.
    Mango has a high global demand. Fruit fungal disease causes post-harvest mango and fruit losses. Conventional chemical fungicides and plastic prevent fungal diseases but they are hazardous to humans and the environment. Direct application of essential oil for post-harvest fruit control is not a cost-effective approach. The current work offers an eco-friendly alternative to controlling the post-harvest disease of fruit using a film amalgamated with oil derived from Melaleuca alternifolia. Further, this research also aimed to assess the mechanical, antioxidant, and antifungal properties of the film infused with essential oil. ASTM D882 was performed to determine the tensile strength of the film. The antioxidant reaction of the film was assessed using the DPPH assay. In vitro and in vivo tests were used to evaluate the inhibitory development of the film against pathogenic fungi, by comparing the film with different levels of essential oil together with the treatment of the control and chemical fungicide. Disk diffusion was used to evaluate mycelial growth inhibition, where the film incorporated with 1.2 wt% essential oil yielded the best results. For in vivo testing of wounded mango, the disease incidence was successfully reduced. For in vivo testing of unwounded mango to which the film incorporated with essential oil was applied, although some quality parameters such as the color index were not significantly affected, weight loss was reduced, soluble solid content was increased, and firmness was increased, compared to the control. Thus, the film incorporated with essential oil (EO) from M. alternifolia can be an environmentally friendly alternative to the conventional approach and the direct application of essential oil to control post-harvest disease in mango.
  • Publication
    Effect of hydrophobic deep eutectic oil-in-water nano coating on the quality preservation of postharvest ‘Harumanis’ mango
    ( 2024-06-20)
    Gidado M.J.
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    Wongs-Aree C.
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    Yusoff N.H.A.
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    Ibrahim R.
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    Laboh R.
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    Ali A.
    A hydrophobic deep eutectic oil-in-water nanoemulsion (HyDEN) was developed as a potential edible coating for preserving 'Harumanis' mango. Preventing water loss in mango during postharvest handling and storage is crucial to maintain their quality and market value. Mango with high respiration rates during storage tend to have shorter shelf life due to issues like softening and over-ripening. Edible coating materials such as lipids, polysaccharides, and proteins have setbacks such as poor water vapor barrier and potential contamination which affect their performance in preserving fruit quality. In this study, a HyDEN coating was prepared to preserve 'Harumanis' mango. The HyDEN coating exhibited good stability, with a high zeta potential value of −42.02 ± 0.12 mV, a robust antioxidant property of 97.89 ± 0.14%, and relatively low mean droplet sizes averaging 210.04 ± 0.89 nm. The application of HyDEN coating effectively extended the shelf life of 'Harumanis' mango. Additionally, it slowed down the ripening process, preserving the fruit's quality in terms of weight loss, firmness, total soluble solids, colour, titratable acidity, pH, radical scavenging rate, browning index, total phenolic content, total flavonoid content and sensory attributes after 20 days of storage, whereas the control fruit began to overripe and deteriorate after 10 days. This study introduces a novel delivery system for applying HyDEN as an edible coating for postharvest fruit preservation.
  • Publication
    Processing, tensile and morphological characteristics of polylactic acid/ Chitosan biocomposites prepared by melt compounding technique
    Biodegradable polymers of polylactic acid (PLA) and chitosan (Cs) has a great potential as alternative candidates to replace conventional synthetic plastic apart to reduce the plastic waste pollution due to the unique properties of superior mechanical strength, feasible processability and rapid degradation. In this work, PLA/Cs biocomposites were prepared via melt compounding and compression moulding techniques in the absence of any plasticizer and additive. The effect of chitosan loading (2.5, 5, 7.5, 10 php) on processing, tensile and morphological characteristics of PLA/Cs were evaluated using internal mixer, universal testing machine and field emission scanning electron microscopy (FESEM), respectively. Processing characteristic indicates PLA/Cs biocomposites demonstrated higher processing torque in comparison to neat PLA due to the increase in melt viscosity and decrease in chain mobility of the polymeric materials. Tensile test results revealed that the maximum strength (54.60 ± 0.51 MPa) and tensile elastic modulus (2.67 ± 0.01 GPa) was attained by PLA/2.5Cs biocomposite. In fact, the addition of chitosan content up to 10 php results in significant decreased in tensile strength and elongation at break of 23.38 ± 0.37 MPa and 0.96 ± 0.04 %, respectively. This is supported by the electron micrograph observation of the PLA/2.5Cs tensile fractured surfaces that exhibits uniform dispersion and good interfacial adhesion between chitosan and PLA matrix which signifies higher tensile properties. However, more agglomeration and poor filler-matrix interaction was observed with further addition of chitosan content of above 7.5 php which implies deterioration in tensile properties. The results suggest that the incorporation of low chitosan loading improve the processing, tensile and polymer compatibility in PLA/Cs biocomposites.