It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Studies evaluate the health effects of bioactive compounds obtained from plants
Researchers from Brazil and Germany study the mechanism of action of phytochemicals from papaya, passion fruit and medicinal plant extracts; results were presented at FAPESP Week Germany.
Fruits and plant extracts contain bioactive compounds that can help treat or prevent diseases. To characterize and understand their mechanism of action, researchers from universities and research institutions in Brazil and Germany have conducted independent but complementary studies.
Some of the results were presented at a lecture session on the future of food and nutrition research on March 25th during FAPESP Week Germany at the Free University of Berlin.
According to Ulrich Dobrindt, a professor at the University of Munich in Germany, medicinal plants contain different types of phytochemicals (natural chemical substances) that neutralize bacterial infections in different ways, thereby boosting the host’s defenses. For this reason, there is growing interest in using extracts from these plants to treat and prevent urinary tract infections, one of the most common infections worldwide, which are currently treated with antibiotics.
“Although their anti-inflammatory, antipyretic and analgesic effects are well known, the active compounds of these plants – such as flavonoids, alkaloids and terpenoids – and their mechanisms of action on pathogen cells have yet to be characterized. Some are antibacterial, but many don’t have this effect,” said the researcher.
In order to further their understanding, German scientists have developed infection models to study the effects of plant extracts on the innate immune response and on the epigenetic regulation of gene expression (biochemical processes that activate and deactivate genes). In bladder cells, for example, they are studying the effect of traditional plants with urological activity, according to the German pharmacopoeia.
In collaboration with researchers at the Federal University of Minas Gerais (UFMG) in Brazil, it was found that some aqueous plant extracts (from species such as Solidago gigantea and Equiseti herba) significantly reduced the adhesion and survival of Escherichia coli in human bladder epithelial cells.
“We observed a drastic reduction in the adhesion and proliferation of this bacterium in bladder cells,” said Ulrich.
Fruit fibers
In Brazil, a group associated with the Food Research Center (FoRC) – one of FAPESP’s Research, Innovation and Dissemination Centers (RIDCs) – has focused on the technological prospection and evaluation of the biological effects on humans of non-digestible water-soluble polysaccharides (bioactive polysaccharides), such as pectins.
Found in papaya, passion fruit and citrus fruits, pectins make up a large portion of the fiber in these fruits and have been linked to a reduction in chronic non-communicable diseases.
However, some of the challenges in extracting these compounds from fruits such as papaya are that they ripen very quickly, resulting in softening of the pulp and chemical modification of the structures of its pectins, which are linked to biological effects such as modulation of the gut microbiota.
“During fruit ripening, enzymes are expressed that modify the structure of the pectins, reducing their beneficial biological effects. Passion fruit and citrus pectins, on the other hand, must be chemically modified in order to present beneficial activities in the intestine,” João Paulo Fabi, professor at the School of Pharmaceutical Sciences of the University of São Paulo (FCF-USP) and coordinator of the project, told Agência FAPESP.
To do this, the Brazilian researchers developed techniques to extract pectin from the albedo of oranges and passion fruit – the white part between the peel and the pulp that is normally discarded when the fruit is processed to make juice – and to modify it in the laboratory to reduce its molecular complexity in order to increase its biological activity.
The development resulted in a patent for the process of extracting pectin from fleshy fruits such as papaya and chayote. A second patent covering the modification of pectin from passion fruit by-products is in the process of being filed.
“We already have a prototype for extracting and modifying these pectins on a laboratory scale. The idea is to obtain a product, such as a flour rich in modified pectin, that could be consumed as a supplement or food ingredient,” said Fabi.
In partnership with other groups, the researchers conducted animal studies to demonstrate the correlation between modified pectins and increased biological activity.
“These preclinical studies can serve as a basis for the development of clinical trials [with modified pectins] as adjuvants to chemotherapy treatment of colon cancer or even as beneficial modulators of the intestinal microbiota,” the researcher said.
Fig. Effect of VivoSight OCT observation on blood vessel density of subjects.The marked test areas for subjects A-D were the left facial skin, left nasal skin, the back of the left hand, and the left elbow skin. The number of biological replicates is 4, the number of experimental replicates is 3.
Skin issues arising from improper diet, routines or allergies are increasingly prevalent. Conditions such as melanin deposition, wrinkles from aging, skin inflammation causing rashes and acne pustules due to Propionibacterium acnes infections are commonly observed.
Free radicals, known for accelerating aging, increase skin wrinkles and aging. Tyrosinase, a crucial enzyme in melanin synthesis, catalyzes the production of melanin, with its oxidation product dopaquinone serving as a substrate for brown and true melanin synthesis. Hence, inhibiting tyrosinase activity offers a strategy to mitigate melanin production and promote skin whitening.
Meanwhile, the promising anti-inflammatory, antioxidant, antibacterial and whitening properties of sea buckthorn polysaccharides and flavonoids have not been systematically validated for skincare applications
“We wanted to systematically verify the skincare functionalities of sea buckthorn flavonoids,” says Yan Zhou, senior and corresponding author of a new study published in the Journal of Dermatologic Science and Cosmetic Technology. “Specifically, the inhibitory effect of sea buckthorn flavonoids on Propionibacterium acnes were assessed by plate antibacterial assays, the antioxidant properties evaluated using an ABTS free radical scavenging assays, and the whitening effect was determined by measuring tyrosinase inhibition with an enzyme labeling instrument.”
Given the insolubility of sea buckthorn flavonoids in water, the researchers designed a nano-milk formulation to enhance their dispersion. Additionally, a gel leave-on mask formulation incorporating glycerol glucoside and hydrolyzed collagen was developed to extend skin contact time and enhance moisturizing and reparative effects.
“We found that seabuckthorn flavonoids indeed exhibited excellent antimicrobial, anti-inflammatory and whitening effects,” shares Zhou. “Participants showed significant improvements in skin parameters, including reduced roughness, increased moisture content, and enhanced pigmentation balance, confirming the practical efficacy of the product.”
This study not only fills the gap in the systematic verification of the multifaceted skincare benefits of seabuckthorn flavonoids and polysaccharides, but also developing a product that efficiently integrates these two active ingredients.
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Contact the author: Ao She, Beijing University of Chemical Technology, Beijing, China. Sheao2002@qq.com
The publisher KeAi was established by Elsevier and China Science Publishing & Media Ltd to unfold quality research globally. In 2013, our focus shifted to open access publishing. We now proudly publish more than 200 world-class, open access, English language journals, spanning all scientific disciplines. Many of these are titles we publish in partnership with prestigious societies and academic institutions, such as the National Natural Science Foundation of China (NSFC).
Journal
Journal of Dermatologic Science and Cosmetic Technology
Study on the anti-free radical, antibacterial, and whitening effects of sea buckthorn extract and its product development
COI Statement
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
Mycobacterium abscessus can cause dangerous lung infections.
Treatment usually requires a combination of antibiotics for more than a year.
Researchers in China report that curcumin, found in turmeric, can enhance treatment with bedaquiline, an antimycobacterial.
Animal studies showed that treatment with the combination led to a faster clearance of the infection.
Washington, D.C.—Mycobacterium abscessus is a fast-growing, pathogenic mycobacteria that can cause lung infections, and people who have respiratory conditions or are immunocompromised face a higher risk. It can also cause skin infections. The microbe is closely related to the one that causes tuberculosis and is naturally resistant to many antibiotics. Infections often require a year or more of a combination of drugs.
A study published this week in Microbiology Spectrum reports a potential way to improve treatment: Add a little spice. Researchers at Shanghai Jiao Tong University, in China, found that adding curcumin boosts the efficacy of bedaquiline, an antimycobacterial used to treat tuberculosis, in combating M. abscessus infections. Curcumin is the compound that gives turmeric its characteristic bright orange color.
“This low-toxicity natural product combined with existing drugs could pioneer new treatment pathways for resistant infections,” said microbiologist Zhe Wang, Ph.D, senior author on the study. “It’s particularly relevant in immunocompromised populations,” Wang added, who are more vulnerable to these infections.
Wang’s lab focuses on innovative approaches to treating infectious disease; those approaches include repurposing known drugs and finding ways to combine natural products with known treatments. They knew that treatment for M. abscessus often leads to poor outcomes—only about half of people who undergo treatment become non-infectious, according to previous studies. Bedaquiline is an antibiotic used to treat multidrug-resistant tuberculosis and has shown some promise in relieving symptoms of non-tuberculosis mycobacterial infections, including M. abscessus. However, the drug does not eliminate all the infectious microbes from a sample.
The researchers, searching for ways to boost the efficacy of bedaquiline, investigated curcumin, which has long been used in traditional Asian medicine to treat a wide variety of conditions. Previous pharmacological studies suggest that curcumin has protective effects against tuberculosis.
In lab studies, the researchers found that bedaquiline alone first inhibited the growth of M. abscessus, but the bacteria began to grow again after 2 weeks. The combination of the drug and curcumin, however, suppressed the growth and reproduction of the bacteria, suggesting that curcumin may act as an antibiotic resistance breaker. In mice, the researchers found that the drug combination slowed or stopped infection better than either compound alone, both in immunocompromised mice and those with a healthy immune system. “The combination demonstrates synergistic enhancement of antibacterial activity and improved infection clearance,” Wang said.
The researchers are now investigating the specific molecular targets that play a role in the mechanisms behind the effects of the combination therapy. They’re also evaluating the combination against other resistant mycobacterial strains and conducting safety assessment to prepare for clinical trials and, down the road, the development of new therapeutics. “This study highlights the innovative value of combining drug repurposing with natural products,” Wang said.
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The American Society for Microbiology is one of the largest professional societies dedicated to the life sciences and is composed of over 37,000 scientists and health practitioners. ASM's mission is to promote and advance the microbial sciences.
ASM advances the microbial sciences through conferences, publications, certifications, educational opportunities and advocacy efforts. It enhances laboratory capacity around the globe through training and resources. It provides a network for scientists in academia, industry and clinical settings. Additionally, ASM promotes a deeper understanding of the microbial sciences to all audiences.
Foodborne diseases pose a significant challenge to achieving the United Nations Sustainable Development Goal 3 of Good Health and Well-Being. Such ailments typically occur due to bacterial contamination during food production, processing, transportation, and storage and can even prove fatal. Therefore, it is imperative to prevent contamination due to microbes at all stages.
In this regard, the food industry currently utilizes chemicals such as benzoate and nitrate. Unfortunately, these preservatives are not deemed as safe and effective natural antibacterial agents. Scientists have recently proposed essential oils, volatile substances produced through the secondary metabolism of plants, as promising alternatives.
In a breakthrough, a team of researchers led by Jun-Won Kang, an Assistant Professor in the Department of Food Science and Biotechnology at Dongguk University, has come up with a novel clove essential oil-based Pickering emulsion formulation with enhanced antibacterial properties. Their findings were made available online on 3 December 2024 and published in Volume 503 of the Chemical Engineering Journal on 1 January 2025.
According to Dr. Kang, “Clove essential oil is known to exhibit excellent antibacterial properties. However, its application has been limited by low water solubility. To overcome this, we decided to explore oil-based Pickering emulsions.”
In this study, the researchers developed a sustainable Pickering emulsion using carbon quantum dots (CQDs), promising solid particles for food applications, derived from clove essential oil residue. Specifically, they synthesized four kinds of CQDs using ultrapure distilled water and ethanol, finding that CQDs with 40% ethanol demonstrated the highest emulsifying efficacy.
CQDs increase the surface roughness of the emulsion, enhancing bacterial adhesion and leading to stronger antibacterial activity compared to conventional emulsions. The present approach not only enhances the antibacterial efficiency of emulsions but also offers a green and eco-friendly alternative to traditional chemical surfactants such as Polysorbate 80. It showcases the upcycling of essential oil extraction byproducts into valuable emulsifying agent nanomaterials, contributing to sustainable material development and waste valorization.
This work is expected to find several interesting applications across numerous fields. The developed Pickering emulsion can be used in food preservation and packaging to enhance shelf life by naturally preventing bacterial contamination. Additionally, since essential oils are already widely used in skincare products, the proposed emulsion could be used in natural cosmetics and topical antimicrobial formulations.
Moreover, the antimicrobial properties of emulsion suggest potential applications in wound dressings, antiseptic formulations, or drug delivery systems. The formulation could also be applied to biopesticides or plant protection products that require stable emulsions with antimicrobial action.
“To summarize, the novelties of our clove essential oil-based technology include reduction of chemical surfactants, health benefits, sustainability, waste reduction, circular economy promotion, advanced antimicrobial features, medical applications, and potential for widespread industrial adoption,” concludes Dr. Kang.
Here’s hoping that this research soon leads to new regulatory standards favouring eco-friendly, bio-based, and non-toxic emulsifiers over synthetic ones, shaping the landscape of multiple industries!
About the institute Dongguk University, founded in 1906, is located in Seoul, South Korea. It comprises 13 colleges that cover a variety of disciplines and has local campuses in Gyeongju, Goyang, and Los Angeles. The university has 1300 professors who conduct independent research and 18,000 students undertaking studies in a variety of disciplines. Interaction between disciplines is one of the strengths on which Dongguk prides itself; the university encourages researchers to work across disciplines in Information Technology, Bio Technology, CT, and Buddhism.
About the author Professor Jun-Won Kang, an Assistant Professor in the Department of Food Science and Biotechnology at Dongguk University, applies cutting-edge nanotechnology to control foodborne pathogens and antibiotic-resistance genes, contributing to food safety and public health. Expanding his research scope, he recently explored probiotic engineering to develop functional and therapeutic food microbiomes. His work spans microbial safety and engineering beneficial microorganisms, aiming to pioneer next-generation probiotics that address global health challenges while ensuring food sustainability. Through interdisciplinary approaches, he advances innovations in food microbiology.
Microscopy images show fluorescently stained mouse brains expressing genes that cause Alzheimer’s disease. Compared with an Alzheimer’s-like brain (left), the more intense green color (right) indicates more neuronal synapses—connections between nerve cells that underlie learning and memory—upon treatment with the drug diAcCA.
LA JOLLA, CA—The herb rosemary has long been linked with memory: “There’s rosemary, that’s for remembrance,” says Ophelia in Shakespeare’s Hamlet. So it is fitting that researchers would study a compound found in rosemary and sage—carnosic acid—for its impact on Alzheimer’s disease. In the disease, which is the leading cause of dementia and the sixth leading cause of death in the US, inflammation is one component that often leads to cognitive decline.
Carnosic acid is an antioxidant and anti-inflammatory compound that works by activating enzymes that make up the body’s natural defense system. While pure carnosic acid is too unstable to be used as a drug, scientists at Scripps Research have now synthesized a stable form, diAcCA. This compound is fully converted to carnosic acid in the gut before being absorbed into the bloodstream.
The research, published in Antioxidants on February 28, 2025, showed that when diAcCA was used to treat mouse models of Alzheimer’s disease, it achieved therapeutic doses of carnosic acid in the brain and led to enhanced memory and synaptic density, or more synapses (representing the connections between nerve cells), in the brain. Because the decline of neuronal synapses is also closely correlated to dementia in Alzheimer’s disease, this approach could counteract the progression of cognitive decline.
Analysis of tissue samples showed the drug also markedly decreased inflammation in the brain. This unique drug is activated by the very inflammation that it then combats and thus is only active in areas of the brain undergoing inflammatory damage. This selectivity limits the potential side effects of carnosic acid, which is on the US Food and Drug Administration’s “generally regarded as safe” (GRAS) list, easing the way for clinical trials.
“By combating inflammation and oxidative stress with this diAcCA compound, we actually increased the number of synapses in the brain,” says senior author and professor Stuart Lipton, MD, PhD, the Step Family Foundation Endowed Chair at Scripps Research and a clinical neurologist in La Jolla, California. “We also took down other misfolded or aggregated proteins such as phosphorylated-tau and amyloid-β, which are thought to trigger Alzheimer’s disease and serve as biomarkers of the disease process.”
Lipton’s group had previously determined that carnosic acid crosses the blood-brain barrier and activates the Nrf2 transcriptional pathway, which turns on antioxidant and anti-inflammatory genes. But the compound oxidizes easily, making it unsuitable as a drug because of its short shelf-life.
In this new study, Lipton and co-author Phil Baran, PhD, the Dr. Richard A. Lerner Endowed Chair in the Department of Chemistry at Scripps Research, synthesized a range of carnosic acid derivatives and selected diAcCA as the best candidate because of its stability, bioavailability, and other drug-like properties. Lipton’s group then treated mouse models with the compound over the course of three months. The group examined the mice by testing their spatial learning and memory in behavioral tests and then analyzing brain tissue under the microscope.
“We did multiple different tests of memory, and they were all improved with the drug,” Lipton says. “And it didn’t just slow down the decline; it improved virtually back to normal.” Analysis of tissues also showed increased neuronal synaptic density and decreased formation of phosphorylated-tau aggregates and amyloid-β plaques.
The mice tolerated diAcCA well. In toxicity studies, the compound even soothed baseline inflammation in the esophagus and stomach as it was converted to carnosic acid.
The group also found that the mice took up about 20% more carnosic acid after ingesting diAcCA than they did after taking plain carnosic acid. Because most carnosic acid oxidizes while being stored or upon ingestion, “diAcCA produces more carnosic acid in the blood than if you took carnosic acid itself,” Lipton explains.
Lipton sees a potential for diAcCA to work in tandem with Alzheimer’s treatments currently on the market. Not only could the drug work on its own by combating inflammation, but “it could make existing amyloid antibody treatments work better by taking away or limiting their side effects” such as a form of brain swelling or bleeding known as ARIA-E and ARIA-H, he says.
Lipton hopes diAcCA can be fast-tracked through clinical trials because of its safety profile. He thinks it could also be explored as a treatment for other disorders marked by inflammation, such as type 2 diabetes, heart disease, and other forms of neurodegeneration such as Parkinson’s disease.
This work was supported by funding from the National Institutes of Health (U01 AG088679, R01 AG056259, R35 AG071734, RF1 AG057409, R01 AG056259, R56 AG065372, R01 DA048882, DP1 DA041722 and S10 OD030332).
About Scripps Research
Scripps Research is an independent, nonprofit biomedical institute ranked one of the most influential in the world for its impact on innovation by Nature Index. We are advancing human health through profound discoveries that address pressing medical concerns around the globe. Our drug discovery and development division, Calibr-Skaggs, works hand-in-hand with scientists across disciplines to bring new medicines to patients as quickly and efficiently as possible, while teams at Scripps Research Translational Institute harness genomics, digital medicine and cutting-edge informatics to understand individual health and render more effective healthcare. Scripps Research also trains the next generation of leading scientists at our Skaggs Graduate School, consistently named among the top 10 US programs for chemistry and biological sciences. Learn more at www.scripps.edu.
Journal
Antioxidants
Article Title
diAcCA, a Pro-Drug for Carnosic Acid That Activates the Nrf2 Transcriptional Pathway, Shows Efficacy in the 5xFAD Transgenic Mouse Model of Alzheimer’s Disease
