Tag Archives: University of São Paulo (USP)

Fungus-produced silver nanoparticles could be used to prevent and treat COVID-19

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This May 6, 2025 news item on phys.org presents an intriguing possibility for COVID-19 prevention,

Silver nanoparticles produced by the fungus Trichoderma reesei could become important allies in the prevention and treatment of COVID-19. Tests carried out on hamsters showed that they not only inhibited the infection but also reduced the viral load in the lungs, easing inflammation in the rodents.

The study paves the way for the development of nasal sprays and other products to combat several viral diseases, such as HIV/AIDS, shingles and influenza.

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A May 7, 2025 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) press release by Maria Fernanda Ziegler (also on EurekAlert but published May 6, 2025) provides more detail about the work,

Silver nanoparticles have been of interest to the pharmaceutical industry due to their high affinity for proteins. Depending on their shape and size, they attract and adhere to these molecules, inhibiting the progression of disease.

“Using computer analysis, we found that the silver nanoparticles produced in our laboratory bind to the spike protein, a kind of key that the SARS-CoV-2 virus uses to enter the host cells and replicate. In this way, they inhibit the entry of the virus into the cell by 50%,” says Roberto do Nascimento Silva, professor in the Department of Biochemistry and Immunology at the Ribeirão Preto Medical School of the University of São Paulo (FMRP-USP) in Brazil and author of the study published in the journal Current Research in Biotechnology. 

Tests in hamsters have shown that the effects of the product may go beyond preventing COVID-19. “The most interesting thing is that the nanoparticles not only prevented the virus from entering the cells but were also able to improve acute lung inflammation, one of the worst complications of COVID-19, proving to be a viable treatment for the disease,” he says.

The researchers found that the silver nanoparticles prevented the activation of the inflammasome – a protein complex in cells responsible for the excessive immune response (cytokine storm) in severe COVID-19 – and the production of interleukin-1beta (IL-1β), a protein involved in the inflammatory response.

“We still need to deepen our understanding of which mechanism is involved in inhibiting the inflammatory response, but given the highly inflammatory nature of COVID-19, it can be inferred that silver nanoparticles reduce this process of cell damage that’s usually associated with disease exacerbation and fatalities,” says Silva.

The work was carried out in collaboration with researchers from FMRP-USP, the Oswaldo Cruz Foundation (Fiocruz, affiliated with the Ministry of Health), the Federal University of Alagoas (UFAL) and the University of Brasília (UnB). The group obtained the silver nanoparticles from T. reesei, known for its industrial application in the conversion of cellulose – an important component of plant biomass – into glucose.

In the laboratory, the fungus begins to multiply in a low-oxygen environment, producing a series of reducing enzymes like a biofactory. These molecules transform the silver into spherical nanoparticles. It is worth noting that the enzymes and proteins present in the T. reesei culture medium act as reducing and stabilizing agents, facilitating the formation of silver nanoparticles with controllable sizes and shapes.

“The biological production of silver nanoparticles is a sustainable biotechnological solution because it avoids the use of toxic chemicals. These nanoparticles can be used in nasal spray formulations, disinfectants, antimicrobial coatings and in medical devices to prevent the spread of the virus,” he says.

Silva also points out that the study, conducted with the aim of stopping the spread of SARS-CoV-2, could serve as a basis for treating other viral diseases. “This strategy has proven to be very interesting, generating products for agriculture and the medical and pharmaceutical industries. Originally, my laboratory investigated the use of silver nanoparticles to fight breast tumor cells. With the pandemic, we focused our work on fighting SARS-CoV-2. The application is broad, and there’s already work in animal studies for HIV and the herpes virus, for example,” he says. 

Although silver is expensive, says the researcher, the production of nanoparticles can be scaled up to produce low-cost products. Another important issue is dosage. “Silver is toxic. That’s why we use a very low dosage, ten times less than what’s considered toxic to the body. And after eight weeks, the body is able to eliminate the metal from the body. So the cost-benefit is worth it,” he says. “The next step in this work is to patent a pharmaceutical formulation and start clinical trials.”

About FAPESP

The São Paulo Research Foundation (FAPESP) is a public institution with the mission of supporting scientific research in all fields of knowledge by awarding scholarships, fellowships and grants to investigators linked with higher education and research institutions in the state of São Paulo, Brazil. FAPESP is aware that the very best research can only be done by working with the best researchers internationally. Therefore, it has established partnerships with funding agencies, higher education, private companies, and research organizations in other countries known for the quality of their research and has been encouraging scientists funded by its grants to further develop their international collaboration.

Here’s a link to and a citation for the paper,

Biogenic silver nanoparticles produced by Trichoderma reesei inhibit SARS-CoV-2 infection, reduce lung viral load and ameliorate acute pulmonary inflammation by Marcus V.M.V. Amaral, Cláudia B. Carraro, Amanda C.C. Antoniêto, Mariana N. Costa, Thais F.C. Fraga-Silva, Ualter G. Cipriano, Rodrigo P.F. Abuná, Tamara S. Rodrigues, Ronaldo B. Martins, Andreia M. Luzenti, Glaucia R. Caruso, Priscyla D. Marcato, Vania L.D. Bonato, Dario S. Zamboni, Bergman M. Ribeiro, Sônia N. Báo, Joao S. da Silva, Flávio P. Veras, Roberto N. Silva. Current Research in Biotechnology Volume 9, 2025, 100277 DOI: https://doi.org/10.1016/j.crbiot.2025.100277

This paper is open access.

It’s all about the cellulose and the graphite: using fallen leaves as the basis for medical and laboratory sensors

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Caption: Sensor printed on leaf by CO2 laser. Credit: Bruno Janegitz

A May 9, 2024 news item on phys.org announces work which makes use of fallen leaves, Note: A link has been removed,

Fabrication of sensors by 3D printing combines speed, freedom of design, and the possibility of using waste as a substrate. Various results have been obtained in a circular economy mode, whereby residues usually thrown away are instead used as low-cost resources.

A highly creative solution involving the printing of electrochemical sensors on fallen tree leaves has now been presented by a team of researchers in Brazil led by Bruno Janegitz, a professor at the Federal University of São Carlos (UFSCar) and head of its Laboratory for Sensors, Nanomedicines, and Nanostructured Materials (LSNANO), and Thiago Paixão, a professor at the University of São Paulo (USP) and head of its Electronic Tongues and Chemical Sensors Lab (L2ESQ).

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A May 8, 2024 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) press release (also on EurekAlert but published May 9, 2024) by José Tadeu Arantes, Note: Links have been removed,

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The initiative was supported by FAPESP and highlighted in an article published in the journal ACS Sustainable Chemistry & Engineering.

“We used a CO2 [carbon dioxide] laser to print the design of interest on a leaf by means of pyrolysis and carbonization. We thereby obtained an electrochemical sensor for use in determining levels of dopamine and paracetamol. It’s very easy to operate. A drop of the solution containing one of these compounds is placed on the sensor, and the potentiostat to which it’s coupled displays the concentration,” Janegitz said.

Simply put, the laser beam burns the leaf in a pyrolytic process that converts its cellulose into graphite [emphasis mine], and the graphite body is printed on the leaf in a shape suited to functioning as a sensor. During the fabrication process, the parameters of the CO2 laser, including laser power, pyrolysis scan rate and scan gap, are systematically adjusted to achieve optimal outcomes.

“The sensors were characterized by morphological and physicochemical methods, permitting exhaustive exploration of the novel carbonized surface generated on the leaves,” Janegitz said.

“Furthermore, the applicability of the sensors was confirmed by tests involving the detection of dopamine and paracetamol in biological and pharmaceutical samples. For dopamine, the system proved efficient in a linear range of 10–1,200 micromoles per liter, with a detection limit of 1.1 micromole per liter. For paracetamol, the system worked well in a linear range of 5-100 micromoles per liter, with a detection limit of 0.76.”

In the tests involving dopamine and paracetamol, conducted as proof of concept, the electrochemical sensors derived from fallen tree leaves attained a satisfactory analytical performance and noteworthy reproducibility, highlighting their potential as an alternative to conventional substrates.

Substituting fallen tree leaves for conventional materials yields significant gains in terms of cost-cutting and above all environmental sustainability. “The leaves would have been incinerated, or at best composted. Instead, they were used as a substrate for high value-added devices in a major advancement for the fabrication of next-generation electrochemical sensors,” Janegitz said. 

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There’s also this, “The Agency FAPESP licenses news via Creative Commons (CC-BY-NC-ND) so that they can be republished free of charge and in a simple way by other digital or printed vehicles.”

Here’s a link to and a citation for the paper,

Green Fabrication and Analytical Application of Disposable Carbon Electrodes Made from Fallen Tree Leaves Using a CO2Laser by Rodrigo Vieira Blasques, Jéssica Rocha Camargo, William Barros Veloso, Gabriel Negrão Meloni, Fernando Amaral Fernandes, Beatriz Fernandes Germinare, Luiz Ricardo Guterres e Silva, Abner de Siervo, Thiago Regis Longo Cesar Paixão, and Bruno Campos Janegitz. ACS Sustainable Chem. Eng. 2024, 12, 8, 3061–3072 DOI: https://doi.org/10.1021/acssuschemeng.3c06526 Publication Date: February 13, 2024 Copyright © 2024 American Chemical Society

This paper is behind a paywall.

Adding as little as 0.1% of rosmarinic acid reduced amount of sunscreen needed to protect skin and more

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Since metallic nanoparticles are now pretty much accepted as being relatively safe ingredients, I don’t write about sunscreens very often anymore. Of course metallic nanoparticles had to be rebranded as ‘minerals’ after some civil society groups raised a great fuss. (See my February 9, 2012 posting “Unintended consequences: Australians not using sunscreens to avoid nanoparticles?” for a rundown of the situation.)

This April 5, 2023 news item about a different kind of sunscreen ingredient on phys.org caught my eye,

An article published in the journal Cosmetics reports an investigation of the effects of including rosmarinic acid, an active antioxidant, in a sunscreen along with two conventional ultraviolet light filters, ethylhexyl methoxycinnamate (against UVB) and avobenzone (against UVA).

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They don’t seem to have tested this new ingredient in any ‘mineral’ sunscreens but it seems an intriguing possibility. Here’s more about rosmarinic acid and why it may be a good addition to sunscreens from an April 5, 2023 Fundação de Amparo à Pesquisa do Estado de São Paulo (São Paulo Research Foundation; FAPESP) press release (also on EurekAlert), which originated the news item, Note: Links have been removed)

The research group increased the sunscreen’s photoprotective efficacy by adding rosmarinic acid at 0.1%, a very small proportion compared with those of conventional UV filters. They believe their findings suggest that incorporating natural molecules with antioxidant activities into sunscreens could decrease the proportion of conventional UV filters in the final product, with the advantage of providing other functional properties.

The product’s performance improved without the need to increase active principle levels, reducing both the amount of sunscreen needed to protect the same skin area and the volume of synthetic chemicals discharged into the environment.

In vitro and clinical trials obtained a 41% increase in sun protection factor (SPF). The higher the SPF, the more sunburn protection increases.

Another advantage of including rosmarinic acid was the addition of antioxidant activity to photoprotection so that the product could be used in antiaging cosmetics, for example.

“Our research on photoprotective systems aims primarily to evaluate potential sunscreen enhancement strategies. We’re interested above all in discovering ways to increase sunburn protection while also improving the stability of the product so that it remains safe and effective for longer,” said pharmaceutical scientist and biochemist André Rolim Baby, last author of the article and a professor at the University of São Paulo’s School of Pharmaceutical Sciences (FCF-USP) in Brazil.

“We’re also looking for products or systems with less environmental impact and ways of reducing the concentration of conventional filters by including natural ingredients that enhance the formulation. And we’re very interested in mapping other cosmetic properties of photoprotective molecules, such as anti-free radical action and protection of biomarkers in the outermost skin layers.”

Multifunctional compound

The investigation was part of a project supported by FAPESP to map chemopreventive properties of various UV filters.

In addition to being an antioxidant, rosmarinic acid, a natural polyphenol antioxidant found in rosemary, as well as sage, peppermint and many other herbal plants, has antiviral, anti-inflammatory, immunomodulatory, antibiotic and anticancer properties.

In a review article published in 2022 in the journal Nutrients, the research group highlighted the beneficial effects of rosmarinic acid as a food supplement, such as improvement in skin firmness and wrinkle reduction.

“In another investigation, we found potential benefits of rosmarinic acid for skin surface hydration, reinforcing the need for more research on the substance in the field of cosmetology,” Baby said.

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Here’s a link to and a citation for the research team’s latest paper,

Photoprotective Efficacy of the Association of Rosmarinic Acid 0.1% with Ethylhexyl Methoxycinnamate and Avobenzone by Maíra de Oliveira Bispo, Ana Lucía Morocho-Jácome, Cassiano Carlos Escudeiro, Renata Miliani Martinez, Claudinéia Aparecida Sales de Oliveira Pinto, Catarina Rosado, Maria Valéria Robles Velasco and André Rolim Baby. Cosmetics 2023, 10(1), 11; https://doi.org/10.3390/cosmetics10010011 Published: 5 January 2023 (This article belongs to the Special Issue Feature Papers in Cosmetics in 2022)

This paper is open access.

Mystery of North American insect bioluminescent systems unraveled by Brazilian scientists

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I’ve always been fond of ‘l’ words and so it is that I’m compelled to post a story about a “luciferin-luciferase system” or, in this case, a story about insect bioluminescence.

Caption: Researchers isolated molecules present in the larvae of the fungus gnat Orfelia fultoni Credit: Vadim Viviani, UFSCar

A September 9, 2020 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) press release (also on EurekAlert but published Sept. 11, 2020) announces research into ‘blue’ bioluminescence,

Molecules belonging to an almost unknown bioluminescent system found in larvae of the fungus gnat Orfelia fultoni (subfamily Keroplatinae) have been isolated for the first time by researchers at the Federal University of São Carlos (UFSCar) in the state of São Paulo, Brazil. The small fly is one of the few terrestrial organisms that produce blue light. It inhabits riverbanks in the Appalachian Mountains in the eastern United States. A key part of its bioluminescent system is a molecule also present in two recently discovered Brazilian flies.

The study, supported by Paulo Research Foundation – FAPESP, is published in Scientific Reports. Five authors are affiliated with UFSCar and two with universities in the United States.

The bioluminescent systems of glow-worms, fireflies and other insects are normally made up of luciferin (a low molecular weight molecule) and luciferase, an enzyme that catalyzes the oxidation of luciferin by oxygen, producing light. While some bioluminescent systems are well known and even used in biotechnological applications, others are poorly understood, including blue light-emitting systems, such as that of O. fultoni.

“In the published paper, we describe the properties of the insect’s luciferase and luciferin and their anatomical location in its larvae. We also specify several possible proteins that are possible candidates for the luciferase. We don’t yet know what type of protein it is, but it’s likely to be a hexamerin. In insects, hexamerins are storage proteins that provide amino acids, besides having other functions, such as binding low molecular weight compounds, like luciferin,” said Vadim Viviani, a professor in UFSCar’s Sustainability Science and Technology Center (CCTS) in Sorocaba, São Paulo, and principal investigator for the study.

The study was part of the FAPESP-funded project “Arthropod bioluminescence“. The partnership with United States-based researchers dates from a previous project, supported by FAPESP and the United States National Science Foundation (NSF), in partnership with Vanderbilt University (VU), located in Nashville, Tennessee.

In addition to luciferin and luciferase, researchers began characterizing a complex found in insects of the family Keroplatidae, which, in addition to O. fultoni, also includes a Brazilian species in the genus Neoditomyia that produces only luciferin and hence does not emit light.

Because they do not use it to emit light, the luciferin in O. fultoni and the Brazilian Neoditomyia has been named keroplatin. In larvae of this subfamily, keroplatin is associated with “black bodies” – large cells containing dark granules, proteins and probably mitochondria (energy-producing organelles). Researchers are still investigating the biological significance of this association between keroplatin and mitochondria.

“It’s a mystery,” Viviani said. “This luciferin may play a role in the mitochondrial energy metabolism. At night, probably in the presence of a natural chemical reducer, the luciferin is released by these black bodies and reacts with the surrounding luciferase to produce blue light. These are possibilities we plan to study.”

Brazilian cousins

An important factor in the elucidation of the United States insect’s bioluminescent system was the discovery of a larva that lives in Intervales State Park in São Paulo in 2018. It does not emit light but produces luciferin, similar to O. fultoni (read more at: agencia.fapesp.br/29066).

In their latest study, the group injected purified luciferase from the United States species into larvae of the Brazilian species, which then produced blue light. The nonluminescent Brazilian species is more abundant in nature than the United States species, so a larger amount of the material could be obtained for study purposes, especially to characterize the luciferin (keroplatin) present in both species.

In 2019, the group discovered and described Neoceroplatus betaryensis, a new species of fungus gnat, in collaboration with Cassius Stevani, a professor at the University of São Paulo’s Institute of Chemistry (IQ-USP). It was the first blue light-emitting insect found in South America and was detected in a privately held forest reserve near the Upper Ribeira State Tourist Park (PETAR) in the southern portion of the state of São Paulo. A close relative of O. fultoni, N. betaryensis inhabits fallen tree trunks in humid places (read more at: agencia.fapesp.br/31797).

“We show that the bioluminescent system of this Brazilian species is identical to that of O. fultoni. However, the insect is very rare, and so it’s hard to obtain sufficient material for research purposes,” Viviani said.

The researchers are now cloning the insect’s luciferase and characterizing it in molecular terms. They are also analyzing the chemical structure of its luciferin and the morphology of its lanterns.

“Once all this has been determined, we’ll be able to synthesize the luciferin and luciferase in the lab and use these systems in a range of biotech applications, such as studying cells. This will help us understand more about human diseases, among other things,” Viviani said.

Here’s a link to and a citation for the paper,

A new brilliantly blue-emitting luciferin-luciferase system from Orfelia fultoni and Keroplatinae (Diptera) by Vadim R. Viviani, Jaqueline R. Silva, Danilo T. Amaral, Vanessa R. Bevilaqua, Fabio C. Abdalla, Bruce R. Branchini & Carl H. Johnson. Scientific Reports volume 10, Article number: 9608 (2020) DOI: https://doi.org/10.1038/s41598-020-66286-1 Published 15 June 2020

This paper is open access.

Evolution-in-materio and unconventional computing

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Training materials such as carbon nanotubes to imitate electronic circuits? Welcome to the world of evolution-in-materio and unconventional computing. From an April 7, 2015 news item on ScienceDaily,

As we approach the miniaturization limits of conventional electronics, alternatives to silicon-based transistors — the building blocks of the multitude of electronic devices we’ve come to rely on — are being hotly pursued.

Inspired by the way living organisms have evolved in nature to perform complex tasks with remarkable ease, a group of researchers from Durham University in the U.K. and the University of São Paulo-USP in Brazil is exploring similar “evolutionary” methods to create information processing devices.

An April 7, 2015 American Institute of Physics (AIP) news release on EurekAlert, which originated the news item, delves into the research itself and the emerging field to which it belongs,

In the Journal of Applied Physics, from AIP Publishing, the group describes using single-walled carbon nanotube composites (SWCNTs) as a material in “unconventional” computing. By studying the mechanical and electrical properties of the materials, they discovered a correlation between SWCNT concentration/viscosity/conductivity and the computational capability of the composite.

“Instead of creating circuits from arrays of discrete components (transistors in digital electronics), our work takes a random disordered material and then ‘trains’ the material to produce a desired output,” said Mark K. Massey, research associate, School of Engineering and Computing Sciences at Durham University.

This emerging field of research is known as “evolution-in-materio,” a term coined by Julian Miller at the University of York in the U.K. What exactly is it? An interdisciplinary field blends together materials science, engineering and computer science. Although still in its early stages, the concept has already shown that by using an approach similar to natural evolution, materials can be trained to mimic electronic circuits–without needing to design the material structure in a specific way.

“The material we use in our work is a mixture of carbon nanotubes and polymer, which creates a complex electrical structure,” explained Massey. “When voltages (stimuli) are applied at points of the material, its electrical properties change. When the correct signals are applied to the material, it can be trained or ‘evolved’ to perform a useful function.”

While the group doesn’t expect to see their method compete with high-speed silicon computers, it could turn out to be a complementary technology. “With more research, it could lead to new techniques for making electronics devices,” he noted. The approach may find applications within the realm of “analog signal processing or low-power, low-cost devices in the future.”

Beyond pursuing the current methodology of evolution-in-materio, the next stage of the group’s research will be to investigate evolving devices as part of the material fabrication “hardware-in-the-loop” evolution. “This exciting approach could lead to further enhancements in the field of evolvable electronics,” said Massey.

Here’s a link to and a citation for the paper,

Computing with carbon nanotubes: Optimization of threshold logic gates using disordered nanotube/polymer composites by using disordered nanotube/polymer composites by M. K. Massey, A. Kotsialos, F. Qaiser, D. A. Zeze, C. Pearson, D. Volpati, L. Bowen, and M. C. Petty. J. Appl. Phys. 117, 134903 (2015); http://dx.doi.org/10.1063/1.4915343

This paper appears to be open access.

Also, the researchers have produced a video,

Credit: Mark Massey/Durham University

Final comment, I am gobsmacked and fascinated.