Search

Over the past five years, there has been growing interest in the design of modified cellulose nanocrystals (CNCs) as nanoscale antimicrobial agents in potential end-user applications such as food preservation/packaging, additive manufacturing, biomedical and water purification. The interest of applying CNCs-based antimicrobial agents arise due to their abilities to be derived from renewable bioresources and their excellent physicochemical properties including rod-like morphologies, large specific surface area, low toxicity, biocompatibility, biodegradability and sustainability. The presence of ample surface hydroxyl groups further allows easy chemical surface modifications for the design of advanced functional CNCs-based antimicrobial materials. Furthermore, CNCs are used to support antimicrobial agents that are subjected to instability issues. The current review summarizes recent progress in CNC-inorganic hybrid-based materials (Ag and Zn nanoparticles, other metal/metal oxide) and CNC-organic hybrid-based materials (polymers, chitosan, simple organic molecules). It focuses on their design, syntheses and applications with a brief discussion on their probable modes of antimicrobial action whereby the roles of CNCs and/or the antimicrobial agents are highlighted. [Display omitted] [ABSTRACT FROM AUTHOR]

This study aims to determine the optimal cooling intervention of a newly designed hybrid cooling vest. 10 males participated in three random experiments, i.e., cooling vest worn during exercise and recovery (ALL-COOL), cooling vest worn during passive recovery (REC-COOL) and control (CON) in a climatic chamber controlled at 37 °C temperature, 60% relative humidity, 0.3 m/s air velocity, and 450 W/m 2 solar radiation to simulate the summer working environment of construction sites. The work–rest protocol was adopted to compare the effectiveness of ALL-COOL and REC-COOL. Physiological (core temperature, skin temperature, and heart rate) and perceptual (ratings of perceived exertion, thermal sensation, and wetness sensation) parameters were measured during the entire heat exposure. The cooling vest worn during exercise improved thermal comfort but did not alleviate heat strain or prolong work duration, as shown by the significant reduction in skin temperature and thermal sensation in ALL-COOL compared with CON (p < 0.05; d = 0.53–0.95, moderate to large effect). The cooling vest used during recovery largely hastened thermoregulatory and cardiovascular strain recovery, as indicated by the significant reduction of body core temperature and heart rate (p < 0.01; d = 0.82–1.04, large effect). Findings implied that post-exercise cooling by the cooling vest can be an appropriate and practical countermeasure in reducing body heat strain in construction sites where repeated bouts of construction work are required. [ABSTRACT FROM AUTHOR]

The aim of the current study is to evaluate airport apron worker’s preferences using two types of cooling vests to identify the factor affecting the preferences for one vest over another. A total of 112 airport apron (43), construction (36), horticultural and cleaning workers (33) participated in two rounds of surveys to evaluate their perceptions of the cooling vests across 18 attributes. For the 17 subjective attributes (except “dislike–like”), the cluster analysis revealed four categories of subjective attributes, while the factor analysis extracted four underlying factors: thermal comfort, fabric hand feel, usability, and tactile comfort. The results of the analysis of variance indicated that airport apron workers were less satisfied with the cooling vests than the other outdoor workers. Multiple linear regression analysis on the resultant preference “dislike–like” of airport apron workers (the dependent variable) and the four underlying factors (the independent variables). The results revealed that usability significantly determined the preference of airport apron workers on cooling vests (adjusted R 2 = 0.84, p < 0.001). Given the underlying factor affecting workers’ preference on cooling vests, the current study provides a practical guidance to optimize the designs of personal cooling vests in view of usability issues for airport apron workers. [ABSTRACT FROM AUTHOR]

Background/Objective: The positive relationship between health benefits or the wellbeing of individuals and their engagement in physical activity is well-documented. Nevertheless, many Americans show no interest or perceive that "exercise is boring" as one of the reasons for not exercising. For these reasons, it is important to promote fun and enjoyment aspects of the activity to motivate people to participate in physical activity. The purpose of this study was to examine the physiological responses and the perception of enjoyment between the Trikke and the bicycle ergometer. Methods: Thirty college students (15 males and 15 females) aged 18-45 years old voluntarily participated in the study and showed up on three occasions. The first session involved a 5-minute instructional video and practice on the Trikke. Participants were then randomized into sessions which involved either riding the Trikke or the bicycle ergometer. Participants of each group performed a 20-minute ride at 75-80% of maximal predicted heart rate. Results: Results of mixed design analysis of variance (ANOVAs) indicated that VO2, energy expenditure, and rate of perceived exertion (RPE) of the participants were significantly (p < 0.001) higher when using the bicycle ergometer than the Trikke, and female participants were able to manipulate the Trikke more efficiently than their male counterparts. Conclusion: Participants were more efficient in using the Trikke than the bicycle ergometer. The Trikke may be an enjoyable alternative for those individuals, particularly women, who have lost interest in traditional forms of exercise. [ABSTRACT FROM AUTHOR]

Abstract: This study aims to determine an optimal recovery time after a participant has exercised to exhaustion in a controlled climatic condition. Ten males and four females volunteers were examined under hot (30°C) and humid (75% relative humidity) environment in a climatic chamber to simulate typical summer outdoor working conditions of construction workers in Hong Kong. The participants (age 31.3 ± 9.3 years; height 168.5 ± 9.8 cm; weight 62.5 ± 7.1 kg; and percentage body fat 22.9 ± 7.2%) performed graded upper body exercise at a target cadence of 70 rotation per minute (RPM) until exhaustion and were recovered inside the climatic chamber until their physiological conditions returned to the pre-exercise level or lower. Physiological Strain Index (PSI) was used as a yardstick to determine the rate of recovery. The physiological conditions of the participants were monitored by recording their ear temperature (to estimate core temperature), heart rate, oxygen consumption, respiratory exchange ratio and Ratings of Perceived Exertion (RPE). It was found that on average a participant could achieve 97% energetic recovery in 40 min; 90% in 35 min; 82% in 30 min; 75% in 25 min; 68% in 20 min; 60% in 15 min; 53% in 10 min; and 46% in 5 min. Linear regression results showed that recovery time is a significant independent variable to determine the rate of recovery (R 2 = 0.95, P < 0.05). Depending on the level of recovery, an optimal recovery time after exhaustion in a hot and humid environment can be determined based on these findings. [Copyright &y& Elsevier]

Nanocrystalline cellulose (NCC), a rod-shaped nanoscale material with exceptional strength and physicochemical properties, can be prepared from inexpensive renewable biomass. Besides its potential use as a reinforcing agent for industrial biocomposites, pristine NCC exhibits low toxicity and poses no serious environmental concerns, providing impetus for its use in bioapplications. Here, we review recent developments in the use of modified NCC for emerging bioapplications, specifically enzyme immobilization, antimicrobial and medical materials, green catalysis, biosensing and controlled drug delivery. We focus on the modification of NCC with chemical functionalities and inorganic nanoparticles, reviewing practical considerations such as reusability, toxicity and scale-up capability. [Copyright &y& Elsevier]

Abstract: Graphene, graphene oxide, sulfonated graphene, and sulfonated graphene oxide (SGO) have been prepared, characterized and tested for the dehydration of xylose to furfural in water. In particular, SGO was proven to be a rapid and water-tolerant solid acid catalyst even at very low catalyst loadings down to 0.5wt.% vs xylose, maintaining its initial activity after 12 tested repetitions at 200°C, with an average yield of 61% in comparison to 44% for the uncatalyzed system. Raman spectroscopy, energy dispersive X-ray spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, 13C solid state nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy and surface area analysis suggested that the aryl sulfonic acid groups were the key active sites for high temperature production of furfural in water. They were more thermally stable under the reaction conditions and acidic than other functional groups attached to the graphene surface. [Copyright &y& Elsevier]

Removal of toxic organic cationic dye, Auramine O (AO), is critical prior to its discharge to the environment. In this work, wood-based colloidal cellulose nanocrystals (CNCs) in their anionic forms (sulfated and carboxylated) were examined as nanoadsorbents for the effective removal of cationic toxic AO. Both sulfated and carboxylated CNCs were characterized by FTIR, DLS, zeta potential, AFM and XRD techniques. The impact of both surface functionalities (half-ester sulfate and carboxylate) of CNCs were studied in relation to the adsorption of AO. The batch adsorption experiments were performed at 0 and 25 °C at different contact time and the highest removal percentage (82 %) and adsorption capacity (20 mg g−1) were obtained for the sulfated CNCs for an equilibrium contact time of 30 min. The kinetic data was fitted to the pseudo-second-order adsorption model, with the highest rate constant (0.55 g mg-1. min−1) related to the sulfated CNCs for the adsorption at 0 °C. The calculated thermodynamics parameters indicated that AO adsorption on both CNC samples was a spontaneous exothermic process with a decrease in the entropy of the system for the sulfated CNCs and an increase in entropy for the carboxylated CNCs. Fitting equilibrium data to four different types of isotherms (Henry, Freundlich, Langmuir and Temkin) showed that Freundlich isotherm was the most suitable to describe the adsorption behavior of AO at either 0 or 25 °C. Overall, this study demonstrated the potential application of sustainable and biodegradable wood-based CNCs as green bioadsorbents for the adsorption of toxic cationic AO dye. [ABSTRACT FROM AUTHOR]

Single-cell protein (SCP) is an evolving biotechnological concept that can potentially align protein production with the global sustainability commitment. This review presents an overview of SCP's current outlook, including production, commercial prospects, and sustainability status. It also elaborates on the potential of the evolving digital twin concept in improving SCP production's efficiency and sustainability performance. An expanding body of work was identified, with well-explored fermentative approaches and varying substrates and microbes. Whereas interest in first-generation substrates such as methane is gradually fading due to their high competitiveness and acquisition cost, second-generation substrates such as lignocellulosic materials and agro-industrial wastes are rapidly evolving due to their availability, low cost, appreciable nutrient density, and alignment with the circular bioeconomy path. Sustainability assessment of current production attaches substantial environmental, mainly global warming and land use offset, and economic savings to SCP production. Moreover, it emphasizes conventional energy use as a hotspot contributor to all impact categories. However, research on life cycle costing, social life cycle assessment, and environmental nutrition concepts is limited. Current trends project rapid market growth for SCP due to expanding feed, food, and nonfood applications. The rapid influx of transformative innovations such as mixed culture biotechnology and the emerging digital twin concept that present catalytic advantages in achieving market growth and sustainability cobenefits are backing these projections. Several sensor and predictive technologies are available to enable an SCP-digital twin path, presenting an opportunity to enhance green and precision SCP production. Despite these innovations, significant efforts are required to overcome limitations concerning toxicity, legislative restrictions, technical constraints, and consumer neophobia to bolster commerce and market value. [Display omitted] • Agro-industrial waste upcycling should frontline circular bioeconomy actions for value recovery. • Single Cell Protein production can align protein supply with global sustainability commitment. • Closing sustainability loop in pulse protein extraction with single cell protein pathway. • Combine environment, economic, social, and nutrition metrics in single cell protein assessment. • Adopt digital twin to for better control and optimization of single cell protein production. [ABSTRACT FROM AUTHOR]

• %Amylose of pea flours had a good correlation with %starch (r = -0.990, p < 0.001). • %Amylose showed positive correlations with %protein and %dietary fiber (p < 0.001). • A higher amylose content increased starch gelatinization temp. of pea flours. • Pea flours with more amylose needed higher heating temp. to give viscosity and gel. • %Amylose increased %resistant starch but did not influence protein digestibility. In this study, ten pea flours covering a broad range of amylose content (37.2–77.6 %, dsb) were characterized for functional and nutritional properties. As the amylose contents increased, the starch contents of the pea flours showed a downward trend (r = -0.990, p < 0.001 in Pearson correlation) but their protein and total dietary fiber contents exhibited an upward trend (r = 0.915, p < 0.001 and r = 0.885, p < 0.001, respectively). A greater amylose content tended to increase starch gelatinization temperatures of the pea flours, which thus required a higher cooking temperature for pasting viscosity development and subsequent gel formation. An increased amylose level reduced in vitro starch digestibility of the cooked pea flours (r = -0.944, p < 0.001) but did not influence in vitro protein digestibility. The insightful findings will be valuable for utilizing the diverse pea lines to create new flour, starch, and protein ingredients. [ABSTRACT FROM AUTHOR]

The consumer demand for starch continues to grow to meet food consumption needs. However, starch producers are increasingly looking towards non-food, industrial applications to access new markets for revenue generation, while aiming for whole crop utilization to meet sustainability metrics. Native starch properties limit its utilization in many industrial applications, therefore, it is modified through different chemical, enzymatic, and physical processes. This review examines innovation in starch transformation processes, and how modified starch and its functional properties can be used in industrial applications beyond the traditional sectors of textiles and papermaking. Currently, the market value of modified starch is 2.7× greater than native starch and is anticipated to increase through next-generation applications (e.g. packaging, energy and regenerative medicine) enabled by emerging technologies in 3D printing and nanotechnology. Opportunities for increasing the use of other botanical starch sources besides industry-leading corn are also presented through the lens of global market trends. [Display omitted] • Non-food, industrial applications are identified as a means for starch producers to access new markets for revenue generation. • The utility of native starch is limited in most industrial applications. • The current market value for modified starch is 2.7× greater than native starch. • Recent advances in chemical, enzymatic, and physical modification of starch are presented. • Traditional and next-generation industrial applications are assessed based on research innovation and global market trends. [ABSTRACT FROM AUTHOR]

Globally, the demand for protein continues to exceed its supply due to the geometric increase in population. For sustainability reasons, the high demand is leading to a shift in interest from animal-based protein, towards consuming high plant protein, sourced mainly from legumes and pulses. Traditional methods for protein extraction have been deployed to ensure availability and convenient utilization of these novel protein sources. Dry and wet fractionation are the two main categories of traditional protein extraction methods, with dry fractionation being more sustainable and frequently used. However, the repercussions trailing these methods keep encouraging research towards greener extraction pathways to ensure more protein availability and sustainability. The key drivers of this transition are increased yield, quality, uniformity and process eco-friendliness. Microwave, ultrasonic energy, pulse electric field, hydrodynamic cavitation extraction and tribo-electrostatic separation, among other novel technologies, appear to be the most likely techniques to dominate in the next few decades. This prospection hinges on available data of their performance efficiency in pulse / legume protein extraction and observed relatively higher yield potentials, protein quality, demand for less water, solvents and energy. The latter inarguably favors the food-energy-water nexus and could contribute considerably to environmental sustainability. Nonetheless, available knowledge cannot suffice effective and sustainable deployments of these techniques in legume protein extraction. Therefore, the gap on process performance and possible optimization of process parameters of these novel technologies deserves urgent attention. The product-process efficiency is highly critical for better understanding of the chances for process scale-up. This has been identified as the present stage of research in this domain. [Display omitted] • Pulses and legumes play essential roles in tackling food security problems globally. • Conventional legume protein extraction methods impact negatively on the environment. • Paucity of studies on green technologies in protein extraction limit their scale up. • With Green technologies, water-food-energy nexus future projection is achievable. • Ultrasound and dry fractionation offer desirable trade off to sustainability. [ABSTRACT FROM AUTHOR]

Protein extraction from pulses has received significant attention in the food processing industry, and as such, several studies have been conducted to develop new methods and to improve upon the conventional methods. In all these, a broad data synthesis to pool and analyze data from these studies to assess and understand the status quo of the pulse-protein extraction technologies, is still wanting. Therefore, there is the need to synthesize data reported by the extensive collection of studies to inform stakeholders on the right pathways for development, critical understanding, and optimization purposes. A meta-analysis was conducted to assess the efficiency of three main extraction processes under two performance indicators of efficiency -protein purity and protein recovery with data points from 41 published studies. The meta-analysis showed that processing conditions affect purity and recovery levels. Several investigations are still to be conducted to understand critical aspects of the pulse extraction processes. Challenges and hotspots requiring further research for a better understanding of some aspects of the extraction process are also presented. • Meta analysis of pulse protein extraction and its impacts on purity and recovery is conducted. • No significant observable difference in protein purity and recovery exists among different pulses. • Thorough studies on effect of voltage on the protein purity is required for the electrostatic separation method. • There are trade-offs between purity and recovery as values of processing conditions increase or decrease. • Hybrid fractionation, the more sustainable and efficient pathway, has been exploited the least. [ABSTRACT FROM AUTHOR]