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How Electrochemistry Is Winning the Green Game

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Advanced research in electrochemistry at the University of Jyväskylä has revealed how various factors, especially electrolyte ions, impact electrochemical reactions. This work, combining theoretical and experimental approaches, contributes to the development of efficient fuel cells and carbon-neutral energy solutions.

New research on electrochemical reactions highlights the critical role of electrolyte ions, aiding in the advancement of sustainable energy technologies.

Electrochemical reactions are central to the green transition. These reactions use the electric current and potential difference to carry out chemical reactions, which enables binding and realizing electric energy from chemical bonds. This chemistry is the basis for several applications, such as hydrogen technology, batteries, and various aspects of circular economy.

Developments and improvement in these technologies require detailed insight into the electrochemical reactions and different factors impacting them. Recent studies have shown that besides the electrode material also the used solvent, its acidity, and the used electrolyte ions crucially impact the efficiency of electrochemical reactions. Therefore, recent focus has shifted to studying how the electrochemical interfaces, i.e. the reaction environment at the electrode and the electrolyte interface shown in Figure 1, impact the outcome of electrochemical reactions.

Figure 1. The electrochemical interface is a very complex reaction environment where several interactions and processes contribute to a chemical reaction. Credit: Marko Melander

Converting Carbon Dioxide

However, understanding the interfacial chemistry using only experimental methods is extremely difficult since they are very thin, only a fraction of a nanometer. Computational and theoretical are therefore crucial as they provide an accurate way to study the electrochemical interfaces at the atomic level and as a function of time. The long-term method and theory development at the Department of Chemistry of the University of Jyväskylä (Finland) has provided new understanding on the chemistry of electrochemical interfaces, in particular on the electrolyte ion effects.

“Our two recent research articles have focused on the electrolyte ion effects in the oxygen and carbon dioxide reduction reactions, which determine the efficiency of fuel cells, hydrogen peroxide synthesis, and conversion of carbon dioxide to carbon-neutral chemical and fuels,” tells the Academy of Finland Research Fellow Marko Melander from Department of Chemistry of the University of Jyväskylä.

Combining Experimental and Computational Results

Researchers at University of Jyväskylä have been collaborating with both experimental and computational groups to understand the electrolyte effects. The work has been recently published in renowned journals, Nature Communications and Angewandte Chemie International Edition.

Figure 2. An oxygen molecule (pink) binds to a potassium ion (green) at the platinum-water interface. Credit: Marko Melander

“In both studies we have focused on the fundamental properties and research, which has necessitated use of highly accurate and demanding experimental, and their combination with the latest simulation methods. For instance, we were able, for the first time, to combine experiments and simulations of quantum mechanical kinetic isotope effects of hydrogen to understand the oxygen reduction reaction. We also developed and applied advanced computational methods to simulate the reorganization of the aqueous electrolyte solutions to reach detailed insight on their joint effect on the reaction mechanism,” elucidates Melander.

Advancing Knowledge in Electrochemical Science

This research provides an atomistic picture on how electrolytes impact electrochemical reactions. One of the identified mechanisms is the bond formation between an ion and the reacting molecule, as shown in Figure 2.

“We were able to show that both the ions control the structure and dynamics of both the electrode surface and the interfacial water through non-covalent interactions. These rather weak interactions then determine the reaction pathway, rate, and selectivity, and hence control the activity and outcome of electrochemical reactions,” explains Melander.

Implications for Renewable Energy Development

While this research focused on the fundamental aspects of electrochemical systems, it can enhance the development of improved electrochemical technologies.

“Utilizing ion and solvent effects may provide a way to tailor the reactivity and selectivity of electrochemical reactions. For instance, the electrolyte can be used to direct the oxygen reduction reaction either towards fuel cell or hydrogen peroxide synthesis applications. The electrolyte chemistry is also an effective way to steer the carbon dioxide reduction towards the wanted, valuable products,” says Melander.

References:

“Cation-induced changes in the inner- and outer-sphere mechanisms of electrocatalytic CO2 reduction” by Xueping Qin, Heine A. Hansen, Karoliina Honkala and Marko M. Melander, 22 November 2023, Nature Communications.
DOI: 10.1038/s41467-023-43300-4

“Cations Determine the Mechanism and Selectivity of Alkaline Oxygen Reduction Reaction on Pt(111)** ” by Tomoaki Kumeda, Laura Laverdure, Karoliina Honkala, Marko M. Melander and Ken Sakaushi, 20 November 2023, Angewandte Chemie International Edition.
DOI: 10.1002/anie.202312841

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December 11, 2023
Chemistry wordoku #022 | Puzzle

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Solve this ‘wordoku’ in the same way as a sudoku with letters instead of numbers (the nine letters once in each row, column and nine-square cell). Once solved, one of the overall diagonals contains the jumbled surname of a UK professor of chemistry, researching in the area of organometallic compounds of the transition metals and lanthanides.

This week’s letters are: D F I M N O R T U

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December 11, 2023
They’re planting trees everywhere and other stories

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In stories we shared on social media, tree planting was once again a popular theme.

Paris to plant first ‘urban forest’ on busy roundabout in drive to build a garden city

This winter, the city will plant 478 trees on the Place de Catalogne near the Gare Montparnasse train station as a flagship project in Socialist Mayor Anne Hidalgo’s drive to cut noise, pollution and tackle global warming.

Planting a revolution in the community garden

A mile north of London’s M25 orbital motorway, a deep-set lane through woodland and fields leads to an undulating 240-acre estate in Hertfordshire shared by three Stuart-Smith siblings. One of those acres is home to Tom and Sue Stuart-Smith’s remarkable not-for-profit enterprise to cultivate good mental health, community and a “plant library”.

Grower produces rarer white variety of poinsettia house plant

Poinsettias originated in Mexico where they originally grew much like a weed.

Insects thrive on solar farms planted with native flowers

Two solar farms in Minnesota saw big increases in bees and other insects after a variety of native grasses and wildflowers were planted among the panels

Over The Course Of Three Summers, She Planted 372,290 Trees In An Effort To Repopulate Canada’s Forests

With deforestation, wildfires, and other kinds of manmade or natural influences, the planet’s naturally growing trees have taken quite a hit. Thankfully, there are conservationists, experts, and caring citizens who are striving to introduce more trees and plants to their areas every year. But have you heard of one person planting over 300,000 trees on their own?

Milkweed, Fire, and Flowers: An Artist’s Take on the Texas Grasslands

Plus, old favorites and the always fascinating Louise Nevelson, at the Amon Carter in Fort Worth

Maternal effects of human-mediated disturbances on the growth and reproductive traits of different ecotypes of an annual invasive plant Erigeron annuus ($)

Among the numerous invasive alien plants, annuals have fast adaptability and evolution via maternal effect in human-mediated disturbance environments, such as chemical and physical controls. The characteristic enables them to quickly disperse and establish new habitats. Thus, understanding the adaptability and evolution of invasive plants in response to multifactorial human-mediated disturbances is crucial for developing effective management strategies to control their spread and minimize their impacts on ecosystems and human activities. In order to test the growth and reproductive responses in both the parent and offspring generations, two ecotypes (clump and scatter) of an annual invasive plant, Erigeron annuus, were subjected to simulated trampling, defoliation (simulated herbivory), and herbicide disturbances.

Forest understorey flowering phenology responses to experimental warming and illumination ($)

Lorer et al. recorded flowering onset, peak, end and duration of 10 temperate forest understorey plant species in two mesocosm experiments to understand how phenology is affected by sub-canopy warming and how this response is modulated by illumination, which is related to canopy change. Furthermore, they investigated whether phenological sensitivities can be explained by species’ characteristics, such as thermal niche.

Global patterns and ecological drivers of taxonomic and phylogenetic endemism in angiosperm genera (OA)

Endemism of lineages lies at the core of understanding variation in community composition among geographic regions because it reflects how speciation, extinction, and dispersal have influenced current distributions. Qian et al. investigated geographic patterns and ecological drivers of taxonomic and phylogenetic endemism of angiosperm genera across the world. They identify centers of paleo-endemism and neo-endemism of angiosperm genera, and show that they are mostly located in the Southern Hemisphere in tropical and subtropical regions, particularly in Asia and Australia.

Slowing taxon cycle can explain biodiversity patterns on islands: Insights into the biogeography of the tropical South Pacific from molecular data (OA)

Islands in the tropical Pacific Ocean are renowned for high biodiversity and endemism despite having relatively small landmasses. However, our knowledge of how this biodiversity is formed remains limited. The taxon cycle, where well-dispersed, earlier colonizers become displaced from coastal to inland habitats by new waves of colonizers, producing isolated, range-restricted species, has been proposed to explain current biodiversity patterns. Keppel et al. integrate the outcomes of phylogenetic studies in the region to investigate the sources, age, number of colonizations, and diversification of 16 archipelagos in the tropical and subtropical South Pacific. They then evaluate whether the results support the taxon cycle as a plausible mechanism for these observations.

Proximate cues of flowering in a subtropical rain forest ($)

Plants have evolved mechanisms to track seasonal variation in environmental resources, enabling them to time key life-history events to appropriate seasons. While the proximate cues for flowering initiation are well documented in the temperate region, it is still unclear what the flowering cues are in the tropics, especially in the subtropics. Chang-Yang et al.’s study compared first flowering dates (FFDs) predicted by eight hypothesized proximate cues concerning photoperiod, mean and directional changes in solar irradiance and warm/cool temperature, and rainfall with flowering dates observed over 19 years of weekly monitoring for 16 species in a subtropical rain forest.

Naturalizations have led to homogenization of the Malesian flora in the Anthropocene (OA)

Worldwide, floras are becoming homogenized at global scales, but regional patterns vary. Holnes et al. present the first assessment for the Malesian phytogeographical region in terms of the timing of introductions, direction, magnitude and drivers of floristic change due to alien plant naturalizations.

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December 11, 2023
Transforming Agriculture With Microbial Fertilizers

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MIT chemists are reducing the carbon footprint of chemical fertilizers by using nitrogen-fixing bacteria as a sustainable alternative. They developed a protective metal-organic coating that enables these bacteria to withstand heat and humidity, enhancing seed germination rates significantly. This innovation could make microbial fertilizers more accessible and promote regenerative agriculture. Credit: SciTechDaily.com

New coating protects nitrogen-fixing bacteria from heat and humidity, which could allow them to be deployed for large-scale agricultural use.

MIT chemical engineers devised a metal-organic coating that protects bacterial cells from damage without impeding their growth or function. These coated bacteria could make it much easier for farmers to deploy microbes as fertilizers. At left, the inset shows the components that create the protective shell of the microbes, as represented in the center inset by triangular formations.

Production of chemical fertilizers accounts for about 1.5 percent of the world’s greenhouse gas emissions. MIT chemists hope to help reduce that carbon footprint by replacing some chemical fertilizer with a more sustainable source — bacteria.

Bacteria that can convert nitrogen gas to ammonia could not only provide nutrients that plants need, but also help regenerate soil and protect plants from pests. However, these bacteria are sensitive to heat and humidity, so it’s difficult to scale up their manufacture and ship them to farms.

Overcoming Bacterial Sensitivity

To overcome that obstacle, MIT chemical engineers have devised a metal-organic coating that protects bacterial cells from damage without impeding their growth or function. In a new study, they found that these coated bacteria improved the germination rate of a variety of seeds, including vegetables such as corn and bok choy.

This coating could make it much easier for farmers to deploy microbes as fertilizers, says Ariel Furst, the Paul M. Cook Career Development Assistant Professor of Chemical Engineering at MIT and the senior author of the study.

“We can protect them from the drying process, which would allow us to distribute them much more easily and with less cost because they’re a dried powder instead of in liquid,” she says. “They can also withstand heat up to 132 degrees Fahrenheit, which means that you wouldn’t have to use cold storage for these microbes.”

Benjamin Burke ’23 and postdoc Gang Fan are the lead authors of the open-access paper, which was recently published in the Journal of the American Chemical Society Au. MIT undergraduate Pris Wasuwanich and Evan Moore ’23 are also authors of the study.

Protective Coating for Microbes

Chemical fertilizers are manufactured using an energy-intensive process known as Haber-Bosch, which uses extremely high pressures to combine nitrogen from the air with hydrogen to make ammonia.

In addition to the significant carbon footprint of this process, another drawback to chemical fertilizers is that long-term use eventually depletes the nutrients in the soil. To help restore soil, some farmers have turned to “regenerative agriculture,” which uses a variety of strategies, including crop rotation and composting, to keep soil healthy. Nitrogen-fixing bacteria, which convert nitrogen gas to ammonia, can aid in this approach.

Some farmers have already begun deploying these “microbial fertilizers,” growing them in large onsite fermenters before applying them to the soil. However, this is cost-prohibitive for many farmers.

Shipping these bacteria to rural areas is not currently a viable option, because they are susceptible to heat damage. The microbes are also too delicate to survive the freeze-drying process that would make them easier to transport.

To protect the microbes from both heat and freeze-drying, Furst decided to apply a coating called a metal-phenol network (MPN), which she has previously developed to encapsulate microbes for other uses, such as protecting therapeutic bacteria delivered to the digestive tract.

The coatings contain two components — a metal and an organic compound called a polyphenol — that can self-assemble into a protective shell. The metals used for the coatings, including iron, manganese, aluminum, and zinc, are considered safe as food additives. Polyphenols, which are often found in plants, include molecules such as tannins and other antioxidants. The FDA classifies many of these polyphenols as GRAS (generally regarded as safe).

“We are using these natural food-grade compounds that are known to have benefits on their own, and then they form these little suits of armor that protect the microbes,” Furst says.

For this study, the researchers created 12 different MPNs and used them to encapsulate Pseudomonas chlororaphis, a nitrogen-fixing bacterium that also protects plants against harmful fungi and other pests. They found that all of the coatings protected the bacteria from temperatures up to 50 degrees Celsius (122 degrees Fahrenheit), and also from relative humidity up to 48 percent. The coatings also kept the microbes alive during the freeze-drying process.

Enhanced Seed Germination

Using microbes coated with the most effective MPN — a combination of manganese and a polyphenol called epigallocatechin gallate (EGCG) — the researchers tested their ability to help seeds germinate in a lab dish. They heated the coated microbes to 50 °C before placing them in the dish, and compared them to fresh uncoated microbes and freeze-dried uncoated microbes.

The researchers found that the coated microbes improved the seeds’ germination rate by 150 percent, compared to seeds treated with fresh, uncoated microbes. This result was consistent across several different types of seeds, including dill, corn, radishes, and bok choy.

Furst has started a company called Seia Bio to commercialize the coated bacteria for large-scale use in regenerative agriculture. She hopes that the low cost of the manufacturing process will help make microbial fertilizers accessible to small-scale farmers who don’t have the fermenters needed to grow such microbes.

“When we think about developing technology, we need to intentionally design it to be inexpensive and accessible, and that’s what this technology is. It would help democratize regenerative agriculture,” she says.

Reference: “Self-Assembled Nanocoatings Protect Microbial Fertilizers for Climate-Resilient Agriculture” by Benjamin Burke, Gang Fan, Pris Wasuwanich, Evan B. Moore and Ariel L. Furst, 30 October 2023, JACS Au.
DOI: 10.1021/jacsau.3c00426

The research was funded by the Army Research Office, a National Institutes of Health New Innovator Award, a National Institute for Environmental Health Sciences Core Center Grant, the CIFAR Azrieli Global Scholars Program, the Abdul Latif Jameel Water and Food Systems Lab at MIT, the MIT Climate and Sustainability Consortium, and the MIT Deshpande Center.

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December 9, 2023
Transforming Ammonia Into a Sustainable Nitrogen Source

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Reversible activation and catalytic transfer of ammonia via a compound of main group elements. Credit: Frank Breher, KIT

Researchers at KIT have unveiled a novel system for the activation and catalytic transfer of ammonia – catalysis is based on main group elements.

Ammonia (NH3), composed of nitrogen and hydrogen, stands as one of the most commonly manufactured chemicals globally. It plays a crucial role in creating numerous nitrogen-based compounds. If amines could be produced by the simple addition of ammonia to unsaturated hydrocarbons, this would be a major breakthrough in chemistry, because amines, the organic derivatives of ammonia, are in high demand in various areas.

They serve as building blocks of agricultural and pharmaceutical chemicals as well as of detergent substances, dyes, lubricants, and coatings. Moreover, amines are used as catalysts in the production of polyurethanes. And amines are applied in gas scrubbers at refineries and power plants.

By breaking the strong bond between nitrogen and hydrogen, i.e. activation, the ammonia molecule may be transferred at least theoretically to other molecules, such as unsaturated hydrocarbons. Transfer of ammonia to ethylene, an important substance in the chemical industry, for instance, would give rise to ethylamine.

This addition is referred to as hydroamination by chemists. However, ammonia and ethylene do not react with each other easily. A catalyst is required for the reaction to take place. Conventional catalysts based on transition metals, however, react with ammonia and become inactive.

“Hydroamination of non-activated alkenes with ammonia, hence, is considered a big challenge or the holy grail of catalysis,” says Professor Frank Breher, head of a research group at the Division of Molecular Chemistry of KIT’s Institute for Inorganic Chemistry (AOC).

Activation and Catalytic Transfer of Ammonia

In cooperation with researchers from Paderborn University and Complutense University of Madrid, Professor Frank Breher and Dr. Felix Krämer from AOC have now come much closer to reaching this challenging goal. “We have developed a system for the activation of ammonia, which is not based on transition metals, but on main group elements. The “atom-economic” process of activation and subsequent transfer of ammonia does not give rise to any waste, which is of particular interest in terms of sustainability,” Breher says. Work is now reported in Nature Chemistry.

The team produced a so-called frustrated Lewis pair (FLP) that consists of an acid as an electron pair acceptor and a base as an electron pair donor. Usually, both react with each other and produce an adduct. If adduct formation is prevented or at least limited, a frustrated situation results and the molecule readily reacts with small molecules, such as ammonia.

“It is crucial to dampen reactivity such that the reaction with small molecules is reversible. Only then will it be possible to use such an FLP in catalysis. We were the first to achieve this with ammonia as a substrate,” Breher reports. The FLP was found to easily react with non-aqueous ammonia in a thermoneutral way and to reversibly split the nitrogen-hydrogen bond of ammonia at room temperature.

For the first time, the researchers present NH3 transfer reactions catalyzed by a catalyst based on main group elements.

“So far, we have converted activated substrates only and no unsaturated hydrocarbons. But we have come much closer to the reaction of our dreams,” Breher says. “We expect that our first proof of principle will initiate further work on the use of N-H-activated ammonia as an easily available and sustainable source of nitrogen.”

Reference: “A crystalline aluminium–carbon-based ambiphile capable of activation and catalytic transfer of ammonia in non-aqueous media” by Felix Krämer, Jan Paradies, Israel Fernández and Frank Breher, 28 September 2023, Nature Chemistry.
DOI: 10.1038/s41557-023-01340-9

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December 8, 2023
Next major assessment of UK higher education research quality postponed until 2029 | News

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The next Research Excellence Framework (REF) exercise has been pushed back to 2029. The national assessment of the UK’s higher education institutions’ research quality has previously been carried out on a seven-year cycle by the UK’s four higher education funding bodies with the last two taking place in 2021 and 2014 and the next originally slated for 2028.

However, according to an announcement in early December, the next REF will be in 2029, with results published in December that year. The extension has been agreed following feedback from a 2023 consultation on key decisions regarding the next REF which represents a shift towards a broader and more holistic approach to the research assessment.

The additional year has been provided in recognition of the complexities for higher education institutions in preparation for using Higher Education Statistics Agency data to determine REF volume measures, fully breaking the link between individual staff and institutional submissions, and the reworking of institutional codes of practice. The REF team said it would provide an updated timeline ‘as soon as possible’.

Further decisions will be announced in spring 2024 and will provide more detail on points of policy for the forthcoming REF cycle.

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December 8, 2023
Invasions of awfully pretty and pretty awful plants and other stories

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Plant invasions are a common theme in the stories we shared on social media recently.

Plant nurseries are exacerbating the climate-driven spread of 80% of invasive species

Researchers have provided detailed maps of how 144 common invasive plant species will react to 2° Celsius of climate change in the eastern U.S., as well as the role that garden centers currently play in seeding future invasions.

Colonizing Plants: How Bougainvillea Conquered the World

Shahnaz Habib on the Relationship Between Colonialism, Natural Science and Travel.

Tiny Forest at Lyndhurst Community of Faith Church may have big benefits

When I visited the beautiful native pollinator garden at the Lyndhurst Community of Faith Church, described in a column last August, congregant John McCumber told me that the church was also planting a “Tiny Forest.” I had never heard the term before and imagined an oversized fairy garden with miniature trees and perhaps a pony ride.

This Raspberry Pi robot dog waters thirsty plants using AI

This Raspberry Pi watering system thinks it’s a dog.

At least 241 invasive plants mapped in 7 South Asian countries; India tops list

Scientists from India and six other countries have come up with an inventory of 241 plants, which were introduced in south Asian countries and have over the years become Invasive Alien Species (IAS). India tops the list with 185 such plant species.

Microbes essential to plants are disappearing due to global warming

Overall, these diminishing bacteria were found to be crucial missing elements from fruitful agroecosystems responsible for yielding food. Could they lead to a nutritional shortage?

Multi-omics analysis reveals activation of jasmonate synthesis and modulation of oxidative stress responses in boron-deficient pea shoots

New study in pea shoots shows boron deficiency dynamically alters metabolism – increasing oxidative stress while reprogramming biosynthesis of lignins, flavonoids and jasmonates. Jasmonate accumulation notably plays role in modulating membrane/cell wall function during deficiency. Findings identify targets like jasmonate signaling and antioxidant capacity for breeding boron deficiency tolerance.

Physical infrastructure and global capacity are both needed to fight biodiversity loss ($)

Kersey and Antonelli respond to recent reporting on the plan to move Kew Herbarium from Kew to Reading.

Generalist and topologically central avian frugivores promote plant invasion unequally across land-bridge islands ($)

Seed dispersal by frugivorous birds facilitates plant invasions, but it is poorly known how invasive plants integrate into native communities in fragmented landscapes. Zhu et al. surveyed plant-frugivore interactions, including an invasive plant (Phytolacca americana), on 22 artificial land-bridge islands (fragmented forests) in the Thousand Island Lake, China. Focusing on frugivory interactions that may lead to seed-dispersal, they built ecological networks of studied islands both at local island (community) and at landscape (metacommunity) levels.

Complex floral traits shape pollinator attraction to flowering plants in urban greenspaces (OA)

Urban greenspaces are recognized as a benefit to pollinator conservation. Selective planting of attractive flowering plants can improve the conservation value of urban greenspaces. However, the functional traits of flowering plants that moderate pollinator preference merits further study. Wang et al. analyzed 98 ornamental plants and spontaneous plant species for ten categories of floral and plant traits across twelve parks or campus greenspaces in Wuhan, a megacity located in central China.

Plant hormones mediate the interaction between oak acorn germination and rodent hoarding behaviour ($)

The interaction between animals and plants for seed dispersal and predation has received much attention; however, the underlying physiological mechanisms driving the responses of both seeds and animals remain unclear. Li et al. conducted a series of behaviour and physiology experiments to examine the role of plant hormones in regulating seed germination and rodent hoarding behaviour in the Quercus variabilis and Leopoldamys edwardsi systems.

The combined effects of habitat fragmentation and life history traits on specialisation in lichen symbioses (OA)

Berlinches de Gea et al. investigate the combined effect of habitat fragmentation, forest structure and life-history traits (growth form and reproductive mode) on the specialisation of lichen-forming fungi (mycobionts) toward their photosynthetic partners (photobionts) in lichen symbioses.

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December 8, 2023
Life-saving cancer gene therapy under investigation after being linked to rare secondary cancers | Business

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The Food and Drug Administration (FDA) has revealed that it is investigating a serious side effect of a revolutionary class of cancer therapies. The agency announced reports of T-cell malignancies in patients receiving CAR (chimeric antigen receptor)-T cell therapies, surprising researchers in the field. CAR-T is often the last resort treatment for patients with blood and blood tissue cancers.

CAR-T requires a patient’s T cells to be extracted and their receptor genetically modified using a viral vector. This programs them to target proteins on the surface of diseased B cells.

CAR-T requires the engineered T cells to be grown up in a lab and reinfused into the original donor. The modified T cell receptor latches onto the target protein and kills cancerous B cells. The first two CAR-T therapies were approved in the US in 2017 to treat a blood cancer.

Patients with no therapy options have been cured by CAR-T therapies, causing great excitement, although costs can be in excess of $350,000 (£260,000) per treatment.

The FDA said it had received clinical trial and post-marketing reports of T-cell malignancies in patients. This risk applies to all currently approved CAR-T therapies, it concluded.

‘Although the overall benefits of these products continue to outweigh their potential risks for their approved uses,’ the FDA said it ‘is investigating the identified risk of T cell malignancy with serious outcomes, including hospitalisations and death, and is evaluating the need for regulatory action.’

The agency listed six approved products under investigation – Abecma and Breyanzi from Bristol Myers Squibb; Yescarta and Tecartus from Kite Pharma/Gilead; Carvykti from Johnson & Johnson; and Kymriah from Novartis.

The possibility of secondary cancers developing after modification of the DNA of T cells using lentivirals or retrovirals had long been a concern. During early clinical trials for an immunodeficiency disorder a therapeutic retroviral vector had inserted genetic material into a pro-cancer gene and caused a leukaemia-like illness.

One possible mechanism in the case of CAR-T therapies is activation of a cancer gene close to the site where the virus integrates, says Michel Sadelain, a CAR-T pioneer at Memorial Sloan Kettering Cancer Centre. Sadelain and colleagues reported earlier this year that disruption of a regulatory gene (TET2) during T cell modification could unleash runaway T cell proliferation. Meanwhile, a recent study profiled how lentivirals and retrovirals can affect CAR-T cell products.

‘It is noteworthy that more of the newly reported cases may have used a lentiviral vector than a γ-retroviral vector, but more data are needed to reach any conclusion,’ says Sadelain. ‘An important mechanism to consider is a genetic predisposition in certain individuals.’

Initial approval of CAR-T by the FDA had required companies to follow patients for 15 years, with observational studies to assess the long-term safety and risk of secondary malignancies. The FDA now says that ‘patients and clinical trial participants receiving treatment with these products should be monitored life-long for new malignancies’.

Gilead said that it had treated 17,700 patients in clinical trials and commercial settings and was not aware of any evidence that Yescarta or Tecartus caused any malignancies. Both Novartis and Bristol-Myers Squibb released similar statements reporting no causal link between their CAR-T therapies and secondary cancers.

Fierce Pharma reported that a search of FDA adverse events revealed a total of 12 T-cell lymphoma cases for Breyanzi, Carvykti, Kymriah and Yescarta.

‘This announcement was surprising to us. We have treated hundreds of patients with CAR-T cells, including over 400 manufactured in our centre, and have not observed any such occurrences,’ says Sadelein. He adds that the incidence of these secondary cancers in around 0.1% of cases should not end CAR-T therapies’ bright future.

Asked what could be done to reduce the risk of secondary cancers, he says: ‘We need to identify the mechanisms to be able to prevent them. One feasible step would be to screen for pre-existing mutations that can promote haematopoietic and T cell expansion.’

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December 7, 2023
Scientists Discover Natural Way To Make Plant-Based Meat More “Meaty”

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Recent research reveals that fermenting alliums like onions with fungi can naturally mimic meat flavors, offering a promising solution for enhancing plant-based meat alternatives without synthetic additives.

Plant-based substitutes like tempeh and bean burgers offer protein-packed choices for individuals looking to cut down on meat. However, mimicking the taste and smell of meat is difficult, and many companies use artificial additives for this purpose. A recent study in ACS’ Journal of Agricultural and Food Chemistry has revealed a promising solution: onions, chives, and leeks can generate natural compounds similar to meat’s savory flavors when fermented with typical fungi.

Innovative Approaches to Natural Meat Flavoring

When food producers want to make plant-based meat alternatives taste meatier, they often add precursor ingredients found in meats that transform into flavor agents during cooking. Or, the flavoring is prepared first by heating flavor precursors, or by other chemical manipulations, and then added to products.

Because these flavorings are made through synthetic processes, many countries won’t allow food makers to label them as “natural.” Accessing a plant-based, “natural” meat flavoring would require the flavoring chemicals to be physically extracted from plants or generated biochemically with enzymes, bacteria or fungi. So, YanYan Zhang and colleagues wanted to see if fungi known to produce meaty flavors and odors from synthetic sources could be used to create the same chemicals from vegetables or spices.

Alliums Unlock Meaty Aromas

The team fermented various fungal species with a range of foods and found that meaty aromas were only generated from foods in the Allium family, such as onions and leeks. The most strongly scented sample came from an 18-hour-long fermentation of onion using the fungus Polyporus umbellatus, which produced a fatty and meaty scent similar to liver sausage.

With gas chromatography-mass spectrometry, the researchers analyzed the onion ferments to identify flavor and odor chemicals, and found many that are known to be responsible for different flavors in meats. One chemical they identified was bis(2-methyl-3-furyl) disulfide, a potent odorant in meaty and savory foods.

The team says that alliums’ high sulfur content contributes to their ability to yield meat-flavored compounds, which also often contain sulfur. These onion ferments could someday be used as a natural flavoring in various plant-based meat alternatives, the researchers say.

Reference: “Sensoproteomic Discovery of Taste-Modulating Peptides and Taste Re-engineering of Soy Sauce” by Manon Jünger, Verena Karolin Mittermeier-Kleßinger, Anastasia Farrenkopf, Andreas Dunkel, Timo Stark, Sonja Fröhlich, Veronika Somoza, Corinna Dawid and Thomas Hofmann, 20 May 2022, Journal of Agricultural and Food Chemistry.
DOI: 10.1021/acs.jafc.2c01688

The authors acknowledge funding from the Adalbert-Raps-Stiftung.

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December 7, 2023
How bad is vaping for your health? We’re finally getting answers

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AS THE old joke goes, when I read about the dangers of smoking, I gave up reading. If you are a vaper, you might feel like you want to stop reading now. Don’t: you need to know this.

I am a vaper. Like many others, I used to smoke and switched to vaping for health reasons. I plan to quit completely, but I haven’t managed it yet. I am sure vaping is better for me than smoking, but I am also sure it is worse than not vaping. I cough in the morning and feel massively addicted to the nicotine. I don’t even really know what I am inhaling. I worry that it will be hard to quit, that I am causing long-term damage to my body and that by vaping, I am susceptible to slipping back down the slope to cigarettes. I also have the same worries for the teenagers I see coming out of school and immediately enveloping themselves in sweet-smelling clouds.

As vaping has increased throughout the Western world, these fears have been repeated often. Part of last month’s King’s Speech in the UK focused on new legislation aiming to create a smoke-free generation in part by cracking down on youth vaping. Worldwide, there have been calls for tougher regulation and more investigation into vaping’s health effects as increasing numbers of children admit to taking up the habit.

But there hasn’t been a huge amount to say on whether fears over health effects are well-founded – until recently. Now, vaping…

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December 6, 2023