This paper formalizes a new multi-scale kinetic model for a process influenced by several limiting factors which are multi-scale in nature. The multi-scale kinetic model incorporates all of the ...dominant factors which can be expressed in the form of first-order kinetics where some of the factors could have delayed effects on the process. The applicability of this new model is demonstrated using a case study of Mangifera pajang antioxidant degradation modelling. The results show that the multi-scale kinetic model can provide improved modelling accuracy, with a Root Mean Square Error (RMSE) of 1.32%. Interestingly, the analysis of the multi-scale model suggests the presence of two groups of antioxidant compounds based on the degradation dynamics in the M. pajang extract. The dominant group of antioxidant compounds contributes about 87% to the total antioxidant concentration, and the degradation of this group is much slower than the non-dominant antioxidant compounds at pH 3. At a high temperature above 60 °C and pH above 7, the fast-degrading group of antioxidants becomes dominant in the extract. Significantly, the proposed multi-scale kinetic model is generic and flexible which can be applied to data-driven modelling of many different processes.
•New generalized multi-scale kinetic model for improved modelling accuracy.•Antioxidant degradation modelling over broad range of experimental conditions.•Reveals two groups of antioxidants in the extract.•Provides more accurate half-life value of antioxidants.
Stability of antioxidant compounds (AC) is always a challenging aspect in the food industry. AC, by nature, can be easily degraded under exposure of different parameters, predominantly high ...temperature during food processing. The thermal degradation of AC greatly impedes their nutritional values. However, it is rather surprising that only little attentions are paid concerning the thermal degradation of AC. Therefore, it is of great interest to describe the potential preservation approaches that reduce the thermal degradation rate of the AC. This review presents the effects of parameters affecting the degradation of AC, as well as an update of recent studies focused on the modeling of thermal degradation kinetics of AC. Our efforts encompass the discussion of numerous formulation strategies to improve the thermal stability of AC. In particular, literature compiled in this review highlight the potential of using various formulation strategies like emulsion, cyclodextrin, liposome, hydrogel, solid lipid nanoparticles, and natural deep eutectic solvent to effectively preserve the AC from thermal degradation. These technologies are efficient and reliable in improving the thermal stability of AC. Interestingly, the use of natural deep eutectic solvent holds great promise in enhancing the thermal stability of AC and its application in stabilizing the AC shall be further explored in the future.
The usefulness of Ananas comosus (pineapple) is not limited its fruits. This study aims to explore the removal of glucose, which are present in clinical waste by pineapple leaf biosorbents derived ...through three pre-treatment methods. Particle size analysis showed the smallest particle were from the steam pre-treated biosorbents and largest particles were from the 5% alkali pre-treated biosorbents. Fourier Transform Infrared Spectroscopy showed that lignin, hemicellulose, and cellulose remained unchanged in both the used and unused biosorbents. Despite the large particle size of the alkali pre-treated biosorbents, up to 70% of glucose was removed which might be due the improvement of the interfacial adhesion during the alkali treatment process.
Display omitted
•Coupling of ZnCl2 and ultrasonication promoted the removal of recalcitrant ECRs.•Highest L-LA yield (90.08%) through SHF was archieved from hydrolysates of P-ECRs.•Nutrient ...combination act as yeast extract substitution for lactic acid bacteria.
This study aims to establish an efficient pretreatment method that facilitates the conversion of sugars from macroalgae wastes, Eucheuma cottonii residues (ECRs) during hydrolysis and subsequently enhances l-lactic acid (L-LA) production. Hence, ultrasonic-assisted molten salt hydrates (UMSHs) pretreatment was proposed to enhance the accessibility of ECRs to hydrolyze into glucose through dilute acid hydrolysis (DAH). The obtained hydrolysates were employed as the substrate in producing L-LA by separate hydrolysis and fermentation (SHF). The maximum glucose yield (97.75 %) was achieved using UMSHs pretreated ECRs with 40 wt% ZnCl2 at 80 °C for 2 h and followed with DAH. The optimum glucose to L-LA yield obtained for SHF was 90.08 % using 5 % (w/w) inoculum cell densities of B. coagulans ATCC 7050 with yeast extract (YE). A comparable performance (89.65 %) was obtained using a nutrient combination (lipid-extracted Chlorella vulgaris residues (CVRs), vitamin B3, and vitamin B5) as a partial alternative for YE.
There are plentiful experimental studies on biomass as heterogeneous catalyst and its reasonable cost, it can be a potential catalyst feedstock for biodiesel production. This study presents the life ...cycle assessment (LCA) of waste cooking oil biodiesel production catalyzed by waste chicken eggshell derived CaO catalyst to validate the suitability of waste chicken eggshell as a green catalyst in biodiesel field. To the best of our knowledge, LCA was first performed for the heterogeneous catalyst, CaO preparation as a subsystem in a biodiesel production. Comparative studies were performed to evaluate the difference of environmental impacts contributed by waste cooking oil, WCO biodiesel production catalyzed by waste chicken eggshell derived CaO with the two different production processes via Jatropha oil as the oil feedstock and potassium hydroxide, KOH as the homogeneous catalyst. Utilization of WCO as the oil feedstock for biodiesel production has lesser environment impact than the Jatropha oil as the WCO biodiesel production does not involve agriculture phase. Likewise, utilization of waste chicken eggshell derived CaO catalyst (heterogeneous catalyst) has less contribution on the overall impact categories than KOH (homogeneous alkali-based catalyst) as the production of KOH required addition of chemical and additives, plus complex purification and neutralization processes are required during the production phase. The overall impact results clearly indicated the best environmental performance of waste chicken eggshell derived CaO of 1.17 Pt was over the traditional KOH catalyst and implementation of Jatropha oil but also identified some bottlenecks that should be addressed for more sustainable solutions.
Display omitted
•Life cycle assessment of waste cooking oil of biodiesel production using waste chicken eggshell derived CaO is performed.•Life cycle assessment in terms of 11 midpoint impact categories of environmental are addressed.•Transesterification step contributed the most damage as it required higher electricity consumption.•This process is confirmed to be more ecofriendly than the Jatropha oil and conventional process.
In recent times, magnesium oxide (MgO) nanoparticles are proven to be an excellent antibacterial agent which inhibits the growth of bacteria by generating reactive oxygen species (ROS). Release of ...ROS by nanoparticles will damage the cell membrane of bacteria and leads to the leakage of bacterial internal components and cell death. However, chemically synthesized MgO nanoparticles may possess toxic functional groups which may inhibit healthy human cells along with bacterial cells. Thus, the aim of the present study is to synthesize MgO nanoparticles using leaf extracts of
Amaranthus tricolor
and photo-irradiation of visible light as a catalyst, without addition of any chemicals. Optimization was performed using Box-Behnken design (BBD) to obtain the optimum condition required to synthesize smallest nanoparticles. The parameters such as time of reaction, the concentration of precursor, and light intensity have been identified to affect the size of biosynthesized nanoparticles and was optimized. The experiment performed with optimized conditions such as 0.001 M concentration of magnesium acetate as precursor, 5 cm distance of light (intensity), and 15 min of reaction time (light exposure) has led to the formation of 74.6 nm sized MgO nanoparticles. The antibacterial activities of MgO nanoparticles formed via photo-irradiation and conventional biosynthesis approach were investigated and compared. The lethal dosage of
E. coli
for photo-irradiated and conventional biosynthesis MgO nanoparticles was 0.6 ml and 0.4 ml, respectively. Likewise, the lethal dosage of
S. aureus
for both biosynthesis approaches was found to be 0.4 ml. The results revealed that the antibacterial activity of MgO nanoparticles from both biosynthesis approaches was similar. Thus, photo-irradiated MgO nanoparticles were beneficial over heat-mediated conventional method due to the reduced synthesis duration.
It is no doubt that plants are a vital centerpiece and contributed immensely in the health care industry. Besides, it has been found that the indigenous people in developing countries had long been ...using local traditional plants for the treatment of diseases. The traditional plants are highly valued for their bioactive compounds which exhibits high antioxidant activity and has the potential in bringing down the risk of diseases. Canarium odontophyllum, also called dabai is one of the underutilized traditional plants consumed by the indigenous people in Borneo Island. The objective of this research is to characterize the antioxidant activity, metal chelating activity, the hydroxyl radical scavenging activity and identifying the potential bioactive compounds of dabai. The antioxidant, metal chelating and hydroxyl radical scavenging activity of dabai extract was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, Fe2+ chelating assay and the hydroxyl radical scavenging assay and found that it yielded an inhibition of 2.31%, 4.89% and 13.06% respectively. Then, chracterization using FTIR revealed the presence of flavonoids, anthocyanins and phenols serving as the potential bioactive compounds for the antioxidant activities. The knowledge gained from the antioxidant capacities and properties of dabai extract are potentially useful for the application of traditional plant medicine as an alternative nutraceutical product in the modern medical industry.
The use of nanometal oxides in nanoagronomy has garnered considerable attention due to their excellent antifungal and plant growth promotion properties. Hybrid nanometal oxides, which combine the ...strengths of individual nanomaterials, have emerged as a promising class of materials. In this study, nanomagnesium oxide (n-MgO) and hybrid magnetic nanomagnesium oxide (m/n-MgO) were successfully synthesized via the ultrasound-mediated sol–gel method. Characterization results, including TGA, XRD, VSM, and FTIR, confirmed the successful synthesis of m/n-MgO. Both n-MgO and m/n-MgO underwent antifungal assays and plant growth promotion ability studies, benchmarked against the conventional fungicide–copper oxychloride. This study bridges a significant gap by simultaneously reporting the antifungal properties of both n-MgO and m/n-MgO and their impact on plant growth. The disc diffusion assay suggested that the antifungal activity of n-MgO and m/n-MgO against F. oxysporum was inversely related to the particle size. Notably, n-MgO exhibited superior antifungal performance (lower minimum inhibitory concentration (MIC)) and sustained efficacy compared with m/n-MgO, owing to distinct antifungal mechanisms. Nanorod-shaped MgO, with a smaller size (8.24 ± 5.61 nm) and higher aspect ratio, allowed them to penetrate the fungal cell wall and cause intercellular damage. In contrast, cubical m/n-MgO, with a larger size (20.95 ± 9.99 nm) and lower aspect ratio, accumulate on the fungal cell wall surface, disrupting the wall integrity, albeit less effectively against F. oxysporum. Moreover, in plant growth promotion studies, m/n-MgO-treated samples exhibited a 15.7% stronger promotion effect compared to n-MgO at their respective MICs. In addition, both n-MgO and m/n-MgO outperformed copper oxychloride in terms of antifungal and plant growth promoting activities. Thus, m/n-MgO presents a promising alternative to conventional copper-based fungicides, offering dual functionality as a fungicide and plant growth promoter, while the study also delves into the antifungal mechanisms at the intracellular level, enhancing its novelty.
Peat is known as problematic ground with low bearing capacity and extensively high compressibility. Bio-cementation or commonly known as microbial-induced calcite precipitation (MICP) has been ...recently introduced as a ground improvement alternative for peat under waterlogged condition. Using isolated bacteria strains P19 and P21 from tropical peat, it is found that unconfined compression strength (UCS) increases with bacteria concentration at a reducing rate. A maximum unconfined compressive strength of 82.05 kPa was measured with bacteria strain P21 at 10
8
CFU/mL. For the range of cementation reagent varying from 0.1 to 4.0 mol/kg, the largest strength improvement occurred at 1 mol/kg and 2 mol/kg using indigenous bacteria and bacteria strain P21, respectively, for peat with sand content of 25%. At 4.0 mol/kg, the cementation reagent has detrimental effect to MICP resulting in significant reduction in strength. Due to MICP, the UCS of peat increases with sand content. Calcium carbonate precipitation results in a reduction of permeability and an increment of strength of peat–sand mixture under a submerged condition up to 28 days.
The therapeutic effects of antioxidant-loaded nanoemulsion can be often optimized by controlling the release rate in human body. Release kinetic models can be used to predict the release profile of ...antioxidant compounds and allow identification of key parameters that affect the release rate. It is known that one of the critical aspects in establishing a reliable release kinetic model is to understand the underlying release mechanisms. Presently, the underlying release mechanisms of antioxidants from nanoemulsion droplets are not yet fully understood. In this context, this review scrutinized the current formulation strategies to encapsulate antioxidant compounds and provide an outlook into the future of this research area by elucidating possible release mechanisms of antioxidant compounds from nanoemulsion system.
