Chemical Industry Research Articles

Catalytically Active Site Mapping Realized through Energy Transfer Modeling.

The demands of a sustainable chemical industry are a driving force for the development of heterogeneous catalytic platforms exhibiting facile catalyst recovery, recycling, and resilience to diverse reaction conditions. Homogeneous-to-heterogeneous catalyst transitions can be realized through the integration of efficient homogeneous catalysts within porous matrices. Herein, we offer a versatile approach to understanding how guest distribution and evolution impact the catalytic performance of heterogeneous host-guest catalytic platforms by implementing the resonance energy transfer (RET) concept using fluorescent model systems mimicking the steric constraints of targeted catalysts. Using the RET-based methodology, we mapped condition-dependent guest (re)distribution within a porous support on the example of modular matrices such as metal-organic frameworks (MOFs). Furthermore, we correlate RET results performed on the model systems with the catalytic performance of two MOF-encapsulated catalysts used to promote CO2 hydrogenation and ring-closing metathesis. Guests are incorporated using aperture-opening encapsulation, and catalyst redistribution is not observed under practical reaction conditions, showcasing a pathway to advance catalyst recyclability in the case of host-guest platforms. These studies represent the first generalizable approach for mapping the guest distribution in heterogeneous host-guest catalytic systems, providing a foundation for predicting and tailoring the performance of catalysts integrated into various porous supports.

Modification of gel properties of Meretrix meretrix (clam) with polysaccharides: physical characterization and interaction mechanism.

This study investigated the contribution of 11 polysaccharides (2%, w/w), including pectin (PC), κ-carrageenan (KC), ι-carrageenan (IC), gellan gum (GG), guar gum (GM), sodium alginate (SA), konjac gum (KG), gum arabic (GA), fucoidan (FC), locust bean gum (LBG), and curdlan (CD), to the gel and microstructural properties of Meretrix meretrix clam gel (MMG). The hardness, springiness and chewiness of MMG with KC, IC, GG, SA and FC addition increased by ~10%-250%, while PC, GM, KG and LBG groups decreased by ~0.6% to 69%. KC, IC, SA, GG and FC decreased the cooking loss rate (CLR) by 69.4% to 88.7% and correspondingly enhanced the water holding capacity (WHC) by 10.2% to 21.4%, which was accompanied by an increased bound water and immobilized water area and high hydrogen proton density. The addition of KC transformed the MMG microstructure from a loose network with large pores to a compact, dense network, reducing lacunarity by 57.9%. The primary intermolecular forces in MMG with the incorporation of KC, IC, GG, SA and FC were hydrophobic interactions and disulfide bonds, which increased by 32.8%-105.3% and 45.6%-114.5% than MMG alone, respectively. Collectively, KC, IC, GG, SA and FC could improve the gel properties of MMG and the strongest synergistic combination was found in the MMG/KC system. This study suggests that the incorporation of polysaccharides is a strategy with potential for modifying the gel properties of shellfish surimi products. © 2024 Society of Chemical Industry.

AAT4IRS: automated acceptance testing for industrial robotic systems

Industrial robotic systems (IRS) consist of industrial robots that automate industrial processes. They accurately perform repetitive tasks, replacing or assisting with dangerous jobs like assembly in the automotive and chemical industries. Failures in these systems can be catastrophic, so it is important to ensure their quality and safety before using them. One way to do this is by applying a software testing process to find faults before they become failures. However, software testing in industrial robotic systems has some challenges. These include differences in perspectives on software testing from people with diverse backgrounds, coordinating and collaborating with diverse teams, and performing software testing within the complex integration inherent in industrial environments. In traditional systems, a well-known development process uses simple, structured sentences in English to facilitate communication between project team members and business stakeholders. This process is called behavior-driven development (BDD), and one of its pillars is the use of templates to write user stories, scenarios, and automated acceptance tests. We propose a software testing (ST) approach called automated acceptance testing for industrial robotic systems (AAT4IRS) that uses natural language to write the features and scenarios to be tested. We evaluated our ST approach through a proof-of-concept, performing a pick-and-place process and applying mutation testing to measure its effectiveness. The results show that the test suites implemented using AAT4IRS were highly effective, with 79% of the generated mutants detected, thus instilling confidence in the robustness of our approach.

Pore Design of POM@MOF Hybrids for Enhanced Methylene Blue Capture

Abstract Adsorption of methylene blue (MB) from aqueous effluents is a key technique to treat wastewater discharge from chemical industries. Toward MB adsorption, porous metal–organic frameworks (MOFs) have been promising owing to their high surface areas and tunable porosity. The incorporation of polyoxometalates (POMs) into MOFs has been found to facilitate MB adsorption due to electrostatic interactions between the anionic POM and the cationic MB. However, it remains unclear how the customizable pore of POM@MOF hybrids affects the capture of MB. In this work, we study the effect of the size and environment of MOFs on the property of MB capture for [Zr6O4(OH)4(BDC)6 (BDC=1,4-benzenedicarboxylate)] (UiO-66) embedding an α-Keggin-type POM [α-SiW12O40]4– (SiW12). Tuning pore size and environment based on ligand engineering of the MOFs suggests that 1) lengthening the organic linkers and 2) functionalization of the linker with −NO2 groups could enhance the MB uptakes. Notably, an increase in the loading amounts of SiW12 on UiO-66 functionalized with −NO2 groups led to outstanding MB capture, comparable to that of representative zeolites such as ZSM-5 and zeolite Y.

Plantain flour: production processes, technological characteristics, and its potential use in traditional African dishes - a review.

This review describes some processes for converting plantain pulp into flour and semolina and the influences that operating conditions can have on some of the technological characteristics (functional and pasting) of this flour. Some traditional African dishes that can be prepared with plantain flour are also presented. A literature review was conducted using a list of keywords and expressions on platforms such as Google, Google Scholar, and ResearchGate. The results show that work carried out to date has mainly focused on a few well known traditional bakery products such as bread, cakes, and biscuits. There has been relatively little research on transforming plantain pulp into flour as part of the preparation of traditional African dishes such as foutou or amala. This work has often been carried out in the laboratory, without any link to local artisanal processes or knowledge of consumer preferences. There is a need to standardize local culinary practices for processing plantain into flour or semolina. The data from this review opens the door for applied research into innovative technological procedures for processing plantain to add value to local dishes adapted to new urban lifestyles, to meet local consumer needs, and to reduce post-harvest losses. © 2024 Society of Chemical Industry.

Economic estimates of invasive wild ungulate damage to livestock producers in Hawai'i.

Invasive ungulates (hoofed mammals), including deer, feral pigs, feral goats, and feral sheep, are known to cause damage to agriculture, property, natural resources, and many other commodities. Most of the information regarding the economic impacts of wild ungulates is from North America, where some of these species are native. To evaluate invasive ungulate damage to livestock producers in the Hawaiian Islands, which have no native ungulates, a survey was distributed to livestock producers across the state. Survey results described how total annual costs are distributed among damage, control, and repairs for survey respondents, who represented a significant percentage of total ranchland acreage across the islands. The estimates, excluding fixed fence installation, revealed an annual cost to livestock producers who responded to the survey of US$1.42 million, which ranged from $3.6 million to $7.5 million when extrapolated to the entire state. The large cost contributors included damage to property, pastureland repair, control costs (excluding fencing), supplemental feed, and predation of calves by wild pigs. Additionally, producers reported spending more than $2 million in upfront fence installation costs. Most of these costs were reported by respondents on the islands of Hawai'i and Moloka'i. Study results revealed substantial damage to state livestock producers due to wild ungulates and are useful in determining an invasive ungulate management strategy that can appropriately aid the most impacted sectors of Hawai'i. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

A novel isolation technique for sweetpotato starch and its application in thermal property characterization.

The utilization of sweetpotato starch in the food industry is significantly influenced by the granule size of the starch. To isolate sweetpotato starch fractions with different sizes, an efficient isolation method is in demand. The differences in thermal properties of starch fractions with different sizes from various sweetpotato varieties were revealed insufficiently. In this study, we devised a time-saving isolation technique to effectively isolate sweetpotato starch fractions based on granule sizes. The new technique was proved applicable for sweetpotato varieties with different flesh colors. The amylose contents of the isolated starch fractions were in the range 16.49-23.27%. A positive association was observed between amylose content, relative crystallinity of starch fractions and their granule size. Conversely, both the swelling power and water solubility at 95 °C displayed a consistent decline from more than 30 g g-1 to lower than 20 g g-1 as the granule size increased. Tp, To and Tc decreased gradually with an increase of starch granule size, while the medium- or small-sized starch fractions showed higher ΔH. In the first stage of thermogravimetric analysis curves, the weight of the small-sized starch fractions decreased the slowest, but no definite pattern was detected in the second or third stage. Therefore, the newly established technique and the results of this study will help better understand the properties of sweetpotato starch fractions with different sizes and certainly provide guidelines for the utilization of sweetpotato starch in food processing and product development. © 2024 Society of Chemical Industry.

Identification and field verification of the aggregation pheromone components produced by male Holotrichia parallela Motschulsky (Coleoptera: Scarabaeidae).

The chafer beetle, Holotrichia parallela, causes damage to numerous economically significant crops worldwide. Adult beetles exhibit aggregation behavior likely mediated by a male-produced pheromone. Advancements in biological research technology have facilitated the identification of insect aggregation pheromones and promoted their applications as bait for trapping and monitoring pests. Currently, only a few active components of aggregation pheromones from Holotrichia species have been identified. However, the specific components of aggregation pheromones produced by H. parallela remain unknown. In this study, we initially observed from Y-tube olfactometer assays that both male and female H. parallela were significantly attracted to volatiles emitted by males, but not to those from females. We then collected hindgut crude extracts of male adults and carried out gas chromatography-mass spectrometry analysis to identify potential aggregation pheromone components. Pentadecyl acetate, cis-13-docosenol, and behenic acid were identified as male-specific compounds in comparison to female extracts, serving as components of the aggregation pheromone in H. parallela. We further evaluated their attractiveness to H. parallea in both laboratory and field experiments. In laboratory settings, pentadecyl acetate, cis-13-docosenol, and behenic acid evoked significant responses to both males and females at specific concentrations, as evidenced by both electroantennography tests and behavioral bioassays. Under field conditions, traps baited with these three compounds captured significantly more H. parallela adults compared to control traps. In this study, we found that pentadecyl acetate, cis-13-docosenol, and behenic acid are specifically present in male H. parallela, serving as aggregation pheromones. Both laboratory and field-trapping experiments suggest their potential as monitoring and controlling tools against H. parallela adults. © 2024 Society of Chemical Industry.

Hop as a phytogenic alternative to antibiotic growth promoters in poultry production.

With the rapid growth of the world's population, the demand for food is also increasing. Poultry accounts for 40% of the global meat sector and therefore represents a significant area for further growth. One starting point for increasing production is to refine the composition of feed to improve the efficiency of growth and nutrient utilization, prevent disease and at the same time reduce environmental impact. Similar considerations have led to the long-standing sub-therapeutic use of antibiotics as growth promoters in animal husbandry, which is associated with the threat of rising antimicrobial resistances and the resulting consequences for human and animal health. In order to circumvent these drawbacks, an increasing number of alternative feed additives are becoming more prevalent. The use of phytogenic feed additives, which includes hops (Humulus lupulus), is regarded as a viable alternative. In addition to its natural availability, hops have been demonstrated to exhibit antimicrobial effects and there is increasing evidence of growth-promoting effects in vivo. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Interactions between prosulfocarb and trifluralin metabolism in annual ryegrass (Lolium rigidum).

Cross-resistance between pre-emergence herbicides is developing in Australian populations of annual ryegrass (Lolium rigidum Gaud.). A previous study has reported that selection with prosulfocarb (a pro-herbicide requiring bioactivation to its phytotoxic sulfoxide) can decrease metabolic resistance to trifluralin. Metabolism of prosulfocarb and trifluralin was investigated in L. rigidum populations with different levels of resistance to prosulfocarb, trifluralin and also pyroxasulfone, which is detoxified by glutathione (GSH) conjugation. Coleoptiles and radicles of herbicide-treated seedlings responded differently to the same herbicide. Radicles had a lower capacity for bioactivation of prosulfocarb, and this was correlated with a lower ability to metabolise trifluralin within and among populations. Coleoptile resistance to prosulfocarb sulfoxide was negatively correlated with abundance of a major polar metabolite. There was no evidence of GSH conjugation with the sulfoxide, making any potential links between prosulfocarb and pyroxasulfone resistance less obvious. Activation and metabolism of prosulfocarb in L. rigidum is complex and differentially regulated in different tissues. Selection with prosulfocarb may ameliorate trifluralin metabolism in the radicles, but the relationship between prosulfocarb and pyroxasulfone resistance is not GSH-mediated. When applying pre-emergence herbicides, care should be taken with the composition of mixtures and rotations to avoid selection of cross-resistance between pyroxasulfone and prosulfocarb. © 2024 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Photocatalytic removal of aldrin and dieldrin using graphene oxide and TiO2‐doped CuFe2O4

AbstractBACKGROUNDConventional treatment processes and existing photocatalysts have proven insufficient in efficiently removing aldrin and dieldrin. Consequently, this study aimed to investigate the removal of aldrin and dieldrin from surface water using a titanium dioxide/graphene oxide/copper ferrite (TiO₂/GO/CuFe₂O₄) nanocomposite.RESULTSThe highest photodegradation efficiencies for aldrin (100%) and dieldrin (99%) were achieved with a TiO₂/GO/CuFe₂O₄ nanocomposite dosage of 1.3 mg L−1, at a sunlight intensity of 9 W m−2 and an optimal photodegradation time of 25 min. The maximum UV absorption wavelength of the TiO₂/GO/CuFe₂O₄ nanocomposite was observed at 365 nm. The quantum yield of the nanocomposite was recorded as 2.69 × 102 mol einstein−1, and its bandgap energy was determined to be 3.31 eV. The first‐order kinetic rate constants for aldrin and dieldrin were calculated as 0.05 and 0.047 min−1, respectively. X‐ray diffraction analysis confirmed the crystal structure of CuFe₂O₄/TiO₂, while Fourier transform infrared spectroscopy detected carboxylic, epoxy, carbonyl and other oxygenated groups within the TiO₂/GO/CuFe₂O₄ nanocomposite. Scanning electron microscopy and transmission electron microscopy images revealed that CuFe₂O₄ was situated on the outer layer of GO. Energy‐dispersive X‐ray analysis identified the elemental composition of the TiO₂/GO/CuFe₂O₄ nanocomposite as comprising GO, C, Cu, Fe, Ti and O. A reusability study demonstrated that the nanocomposite maintained excellent performance, achieving 99% removal efficiency after 79 cycles and 97% after 100 cycles.CONCLUSIONSThe TiO₂/GO/CuFe₂O₄ nanocomposite effectively removed aldrin and dieldrin from surface water. This nanocomposite holds promise for the remediation of other aquatic ecosystems, such as bays, rivers and ocean waters. © 2024 The Author(s). Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).

Yeast cell biocarrier for the encapsulation of ascorbic acid: effect of plasmolysis process, suspension media and ascorbic acid levels on the physicochemical, morphological and bioactive properties of microcapsules.

Ascorbic acid is a water-soluble vitamin and shows weak stability against external factors such as heat, oxygen, light etc. Due to its lower stability, encapsulation is an effective process for the preservation of its activity. Although there are a wide variety of encapsulation methods, the technique of encapsulation with yeast cells has been followed with increasing interest in recent years. In this study, encapsulation possibilities of ascorbic acid by yeast cells were investigated. In this context, Saccharomycess cerevisiae yeast cells in plasmolyzed and non-plasmolyzed forms were used in two different suspension media (water and ethanol) and effect of ascorbic acid concentrations (10, 20 and 50 g per 10 g yeast) were studied. A total of 12 different yeast microcapsule samples were produced and some physicochemical, bioactive and structural characterizations were performed. The ascorbic acid level of yeast microcapsule samples was determined as 206.4-713.9 and 202.8-726.1 mg g-1 for plasmolyzed and non-plasmolyzed yeast cell types, respectively. ABTS radical scavenging activity increased from 27.23 to 233.04 μg TE g-1 by increased ascorbic acid levels. Ascorbic acid capsules were used in soft candy processing against free ascorbic acid and it was found that 47.9% ascorbic acid loss was detected for control sample at the 24-day storage while the ascorbic acid loss was approximately 25% for yeast microcapsules. It was concluded that yeast cells are capable of preserving ascorbic acid stability during storage and yeast cells can be used effectively and safely for the manufacturing of the ascorbic acid microcapsules. © 2024 Society of Chemical Industry.

Integrating solid oxide electrolysis cells and H2-O2 combustion for low-emission high-temperature heating with heat pump in the chemical industry

Low-emission high-temperature heating could be achieved by exploiting electrical heating, clean fuel, or carbon capture. However, it is difficult to replace current coal or natural gas furnaces in some places because the high-temperature thermal demand needs combustion. In the present work, the green hydrogen production process by solid oxide electrolysis cells (SOEC) and H2-O2 combustion is integrated into ethylene production. The working conditions of electrolyzer and furnace are analyzed. The SOEC should work over 800°C to keep endothermic state no matter the current density. To produce the hydrogen of 80 MW heat value, the electric consumption is at least 69.4 MW. With the high-temperature waste heat of 7.76 MW, an additional 3 MW power is required for water electrolysis. The heat released during condensation of combustion products is 30.52 MW, much higher than 13.19 MW from SOEC products. Therefore, the heat pump is necessary to recycle the waste heat of water condensation and generate steam as the electrolysis ingredient and cooling medium, which saves 63 % of energy. Although the total energy consumption increases by 11.23 % from 80.23 MW to 89.24 MW, the CO2 emission drops by 84.28 %.

Process Intensification of Gas–Liquid Separations Using Packed Beds: A Review

The gas–liquid multiphase process plays a crucial role in the chemical industry, and the utilization of packed beds enhances separation efficiency by increasing the contact area and promoting effective gas–liquid interaction during the separation process. This paper primarily reviews the progress from fundamental research to practical application of gas–liquid multiphase processes in packed bed reactors, focusing on advancements in fluid mechanics (flow patterns, liquid holdup, and pressure drop) and the mechanisms governing gas–liquid interactions within these reactors. Firstly, we present an overview of recent developments in understanding gas–liquid flow patterns; subsequently we summarize liquid holdup and pressure drop characteristics within packed beds. Furthermore, we analyze the underlying mechanisms involved in bubble breakup and coalescence phenomena occurring during continuous flow of gas–liquid dispersions, providing insights for reactor design and operation strategies. Finally, we summarize applications of packed bed reactors in carbon dioxide absorption, chemical reactions, and wastewater treatment while offering future perspectives. These findings serve as valuable references for optimizing gas–liquid separation processes.

Polyphenols Regulate the Activity of Endocrine-Disrupting Chemicals, Having Both Positive and Negative Effects

Endocrine-disrupting chemicals (EDCs) are chemical substances that can interfere with any hormone action. They are categorized according to origin and use, such as industrial chemicals like polychlorinated biphenyls (PCBs) and polybrominated biphenyls (PBBs), plastics like bisphenol A (BPA), plasticizers like phthalates, pesticides like dichlorodiphenyltrichloroethane (DDT), fungicides like vinclozolin, and pharmaceuticals like diethylstilbestrol (DES). Natural EDCs, such as phytoestrogens, are present in the diet of both humans and animals. Polyphenols are a large group of natural compounds derived from plants and are found in beverages and food. They are grouped based on their chemical structure into flavonoids and nonflavonoids and are reported to have many beneficial effects on health, including, but not limited to, anticancer, antioxidant, and anti-inflammatory effects. Moreover, polyphenols have both pro- and antioxidant characteristics, and due to their antioxidant and anti-inflammatory potential, they presumably have a protective effect against damage induced by EDCs. However, polyphenols may act as EDCs. In this review, we report that polyphenols regulate the activity of EDCs, having both positive and negative effects. Hence, a better understanding of the associations between EDCs and polyphenols will allow the establishment of improved approaches to protect human health from EDCs.

Ferulic acid: extraction, estimation, bioactivity and applications for human health and food.

Ferulic acid ((E)-3-(4-hydroxy-3-methoxy-phenyl) prop-2-enoic acid) is a derivative of caffeic acid found in most plants. This abundant phenolic compound exhibits significant antioxidant capacity and a broad spectrum of therapeutic effects, including anti-inflammatory, antimicrobial, anticancer, antidiabetic, cardiovascular and neuroprotective activities. It is absorbed more quickly by the body and stays in the bloodstream for a longer period compared with other phenolic acids. It is widely used in the food (namely whole grains, fruits, vegetables and coffee), pharmaceutical and cosmetics industries. The current review highlights ferulic acid and its pharmacological activities, reported mechanisms of action, food applications (food preservative, food additive, food processing, food supplements and in food packaging in the form of edible films) and role in human health. In the future, the demand for ferulic acid in the food and pharmaceutical industries will increase. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The influence of storage conditions on hygiene condition and eicosapentaenoic acid oxidation in Nannochloropsis algae for sustainable food supply.

Nannochloropsis algae contain approximately 20% polyunsaturated fatty acids (PUFA) and hold significant potential for high-quality eicosapentaenoic acid (EPA) food industrialization. However, EPA in Nannochloropsis sp. is prone to oxidation, and microbial growth is a critical factor affecting the shelf life of fresh food. Storage composition and temperature are primary factors influencing microbial growth, yet these aspects are not fully understood. This study investigates the effects of temperature and encapsulation on EPA content in nano-products over time. Nano-powder and nanobeads derived from Nannochloropsis sp. served as raw materials. Additionally, changes in aerobic plate counts and coliform groups were monitored. The results indicated that nanobeads, due to their more complex processing and less mature packaging, were more susceptible to coliform contamination compared to nano-powder. In terms of EPA stability, nanobeads exhibited a longer storage life than nano-powder. The oxidation rate of both nano-powder and nanobeads was faster at 37 °C than at 25 °C. These findings can inform general shelf life estimation, rapid detection of total lipid content in nano-products and macro extraction of nano-oil. Moreover, they have significant implications for delaying EPA oxidation in nano-products and improving hygienic quality control for microbial detection. © 2024 Society of Chemical Industry.

Spent coffee grounds as an alternative fertilizer: impact on bioaccessibility of antioxidants and commercial quality of lettuce.

During the processing of spent coffee grounds (SCGs) several residues are obtained, which are mostly disposed of in landfills. There is an urgent need for a comprehensive waste management strategy for these residues. This study evaluates the potential of SCGs as a biofertilizer by assessing their effects on lettuce leaves and the release of antioxidants following in vitro digestion and fermentation. Lettuce plants were grown with different amounts of SCGs (0-150 g kg-1) in the substrate. High SCG concentrations in the soil generated lighter colored tissues, a decrease in the green color, less root development, and lower dry weight of leaves (P < 0.05). The SCG levels also affected the release of antioxidants by the final product. This effect was more pronounced in the digested fraction: applying the Ferric Reducing Antioxidant Power (FRAP) method, the addition of SCGs from 10 g kg-1 to 125 g kg-1 increased the amount of antioxidant from 43.88 ± 4.81 to 105.96 ± 29.09 μmol Trolox g-1 of dry weight (P < 0.05). The Indigo Carmine Reducing Capacity (ICRED) method also showed a similar trend, but in this case the highest value was obtained with 150 g kg-1 of SCGs (16.41 ± 3.93 mmol catechin g-1 of dry weight) (P < 0.05). Moreover, in the fermented fraction a significant increase in the antioxidant released was found with low levels of SCG(P<0.05), while lettuces fertilized with intermediate amounts of SCGs (25 and 50 g kg-1) presented the highest amount of insoluble antioxidant (P < 0.05). A compromise should be found in order to achieve a product with a high antioxidant capacity and an acceptable visual quality. © 2024 Society of Chemical Industry.

Volatilome of the maize phytopathogenic fungus Fusarium verticillioides: potential applications in diagnosis and biocontrol.

Fusarium verticillioides is a maize fungal phytopathogen and a producer of volatile organic compounds (VOCs) and fumonisin B1 (FB1). Our aim was to study the volatilome, conidial production, ergosterol and FB1 biosynthesis in maize cultures over a 30-day incubation period (5, 10, 15, 20, 25, 30 days post inoculation [DPI]). The effect of pure VOCs on the same parameters was then evaluated to study their potential role as biocontrol agents. In total, 91 VOCs were detected, with volatile profiles being more similar between 5 and 10 DPI compared with 15, 20, 25 and 30 DPI. Ergosterol content increased steadily with incubation time, and three growth stages were identified: a lag phase (0 to 15 DPI), an exponential phase (15 to 20 DPI) and a stationary phase (20 to 30 DPI). The maximum concentration of FB1 was detected at 25 (0.030 μg FB1/μg ergosterol) and 30 DPI (0.037 μg FB1/μg ergosterol), whereas conidial production showed a maximum value at 15 DPI (4.3 ± 0.2 × 105 conidia/μg ergosterol). Regarding pure VOCs, minimal inhibitory concentration values ranged from 0.3 mm for 4-hexen-3-one to 7.4 mm for 2-undecanone. Pure VOCs reduced radial growth, conidial production and ergosterol and FB1 biosynthesis. The marked resemblance between VOC profiles at 5 and 10 DPI suggests that they could act as early indicators of fungal contamination, particularly 4-ethylguaiacol, 4-ethyl-2-methoxyanisole, heptanol and heptyl acetate. On the other hand, their role as inhibitors of fungal growth and FB1 biosynthesis prove their great potential as safer alternatives to control phytopathogenic fungi. © 2024 Society of Chemical Industry.

Alkaline-resistant covalent organic framework membranes for selective hydroxide ion separation

Alkali holds a pivotal role in the chemical industry, however, the substantial discharge of alkaline wastewater causes a severe waste of resources and environmental pollution. Conventional polymer membranes have ether bonded backbones and form randomly assembled nanochannels, suffering from a weak alkali resistance and a low hydroxide ion selectivity. Covalent organic frameworks (COFs), known for their robust framework structure, highly ordered channels, and tunable channel chemistry, have been considered as the competent candidate for alkaline-resistant membranes for selective hydroxide ion separation. Herein, we fabricate a β-ketoenamine COF (TpTAPB) membrane with a high alkaline resistance via the interfacial growth strategy. After post-sulfonation, the negatively charged channels of sulfonated TpTAPB membrane allows OH– with smaller size and lower charges to pass through while repulsing WO42- ions, achieving a selectivity of OH–/WO42- up to ∼ 60 and surpassing commercial and most reported polymeric membranes. This work expands the application scope of COF membranes in selective alkali separation.