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)
Saturday, March 15, 2025
Tapuy rice wine fermentation yields possible anti-aging superfood
“Tapuy” rice wine starts out as a mixture of black and white glutinous rice (A), which is fermented using a starter culture or “bubod.” After a month, the solid residues from the fermentation process or “lees” (B) are filtered out and usually discarded.
Filipino researchers have found a way to optimize the traditional procedure for making Philippine rice wine or “tapuy” to produce a potential superfood rich in anti-aging compounds and antioxidants.
Edward Kevin B. Bragais from the Ateneo de Manila University and Paul Mark B. Medina from the University of the Philippines studied the effects of different starter cultures—that is, the specific set of microorganisms used to jumpstart the fermentation process, locally called “bubod”—on the solid leftovers from winemaking. These often discarded remnants, called “lees,” are mostly made up of rice residues, yeast, and other microbial byproducts.
The researchers found that by optimizing the fermentation process with a well-defined microbial culture, tapuy lees could become a valuable source of natural compounds with potential medical and nutritional benefits.
Tapuy lees made using an optimized starter culture mix were found to contain high levels of polyphenols—compounds known for their ability to fight oxidative stress, inflammation, and cell damage. More remarkably, test animals fed extracts from tapuy lees produced with the improved starter culture showed very high antioxidant activity, significantly extending their lifespan, motility, and reproductive health. The extract also boosted levels of superoxide dismutase, an enzyme crucial for protecting cells from age-related deterioration.
These results suggest that tapuy lees could be repurposed as a health food to combat aging and oxidative stress-related diseases. However, the researchers stressed that these are just preliminary findings based on animal tests, underscoring the need for clinical trials to explore potential benefits in humans. If future studies confirm these effects, this overlooked waste product of rice wine production could become a valuable asset in promoting longevity and public health.
A series of photos showing how a sample of blue-dyed water freezes, losing its blue colour, over a time period of 42 minutes. After 34 minutes, clear ice completely surrounds a still-liquid, blue pocket of water. When this pocket of water freezes a few minutes later, it generates enough outward pressure to crack the glass container. Credit: Menno Demmenie (UvA).
Have you ever left a bottle of liquid in the freezer, only to find it cracked or shattered? To save you from tedious freezer cleanups, researchers at the University of Amsterdam have investigated why this happens, and how to prevent it. They discovered that while the liquid is freezing, pockets of liquid can get trapped inside the ice. When these pockets eventually freeze, the sudden expansion creates extreme pressure – enough to break glass.
“Newton had an apple fall on his head. I found my freezer full of broken glass,” jokes Menno Demmenie, first author of the new study that was recently published in Scientific Reports.
He continues, more seriously: “The usual explanation for frost damage is that water expands when it freezes, but this does not explain why half-filled bottles also burst in our freezers. Our work addresses how ice can break a bottle even when it has plenty of space to expand into.”
To understand this process, the researchers used a special dye, methylene blue, to track freezing in open cylindrical glass containers. The dye easily dissolves in water and turns it blue. The dye becomes transparent when the water freezes, as it gets pushed out of the ice crystals. This allows the researchers to see exactly when and where ice forms.
Having filmed tens of samples of blue-dyed water freezing in a –30 °C environment, the researchers cracked the case. Ice breaks glass when the top surface of the water – the one open to air – freezes first. The rest of the water naturally freezes from the outside in, creating a pocket of liquid water surrounded by ice on all sides. When this pocket freezes too, it exerts an extreme amount of pressure on its surroundings, in many cases enough to break glass.
The researchers estimate the pressure exerted by the ice in their experiments to be around 260 megapascals, enough to dent high-strength steel and four times as much as their glass vials can withstand.
Smaller, water-repellent bottles can save the day
By testing glass containers of different sizes and with different surface coatings, the research team discovered that there are two ways to reduce the risk of trapped pockets of water forming.
The first way is to ensure the water gets colder before it begins to freeze. While water can start freezing at 0 °C, it is possible for liquid water to get ‘supercooled’ to subzero temperatures. Freezing needs to start somewhere, and the start of the phase transition can be delayed.
Supercooled water freezes differently than water that freezes closer to the freezing point. Rather than growing as a crystalline block, it freezes along fingerlike branches (‘dendrites’). In the experiments, this type of freezing turns the dyed water a darker shade of blue before it freezes completely.
The researchers discovered that this unusual ice growth results in a large amount of small air bubbles getting trapped within the ice, something which appears to relieve enough pressure to prevent fracturing. “The discovery of the link between these air bubbles and the freezing of supercooled water came as a surprise, and we hope to investigate this in more detail in future work,” comments Demmenie.
Supercooling and the subsequent bubble formation was seen more often in narrower bottles. Comparing two bottles of different sizes filled with the same amount of water, the water in the smaller bottle cools down faster thanks to the larger surface it has per unit volume. This increases the chance of water cooling further below 0 °C before it starts to freeze.
The second way to prevent trapped liquid pockets is to make sure that not the top surface, but the bottom of the container freezes first. So long as the top surface doesn’t freeze over before the rest of the water does, the ice will simply expand into the open space above.
The team found that the shape of the water’s surface plays a key role. In untreated glass containers, and in those coated with a layer that attracts water (being hydrophyilic), the water surface curves up against the glass. Thanks to the water molecules at the edge having less freedom to move, this region tends to be the first to freeze.
Water in containers with water-repelling (hydrophobic) coatings instead has a flat surface. Thanks to this, it is much more likely to freeze from the bottom up, preventing trapped liquid pockets from forming and reducing the risk of breakage.
So, what do we learn from this? If you don’t want shattered bottles in your freezer, choose smaller bottles and ones with more water-repelling surfaces. (Many plastics are more water-repelling than glass - think of the PET bottles that many soft drinks come in, or of hard plastic like the PP used for Dopper bottles.) Beyond avoiding messy kitchen disasters, these new findings will also help with understanding and preventing frost damage in other places, including buildings, roads and historical artifacts.
Credit: Fritz Freudenberger, Bigelow Laboratory for Ocean Sciences
Bigelow Laboratory scientists have advanced an exciting method for linking the activity of individual microbes to their unique genetic code, providing the first application of the approach to sediments. Their findings were recently published in The ISME Journal.
The method combines single cell genomics and flow cytometry to quantify individual rates of respiration for different taxa. It revealed that low-oxygen sediments from the Maine coast host a diverse microbial community that appears to thrive in an environment where they’re regularly subject to disruption from rapid temperature changes, tides, and more.
“Marine sediments are important ecosystems for active chemical cycling, and some of the most microbially diverse communities found on Earth live there,” said Melody Lindsay, a research scientist at Bigelow Laboratory who led the study. “It was a natural — and fascinating — place to advance our method for illuminating microbial activity using single-cell respiration rates.”
The paper features researchers from Bigelow Laboratory’s Single Cell Genomics Center and Center for Aquatic Cytometry, as well as several undergraduate interns who aided with field sampling and laboratory experiments.
Shallow coastal sediments help control the flow of energy and nutrients from land to ocean. Because oxygen penetrates only a few millimeters below the surface, microbes living in this environment tend to rely on chemical processes other than respiring, or “breathing,” oxygen to survive. Yet, disturbances like sedimentation and burrowing animals regularly introduce oxygen and organic matter into the subsurface environment. The team aimed to understand the impact of this mixing and physical disruption.
“We know the abundance and diversity of ocean sediment microbes is much greater than in the water column above, but we know far less about their actual functions and activities,” said Senior Research Scientist David Emerson, a co-author on the paper. “This method provides a powerful way to reveal new knowledge about a vast, and vastly understudied, part of the marine environment.”
Though scientists have traditionally measured the rates of chemical turnover and other processes for the microbial community as a whole, this larger effort is revolutionizing understanding of activity at the individual level — and how that links to genomic potential.
The revolutionary new method was developed by Bigelow Laboratory from a $6 million grant from the National Science Foundation. In 2022, the researchers first applied the method to the surface ocean, showing how a tiny proportion of microbes consume most of the oxygen. Last year, they tested it with samples from an aquifer deep below Death Valley, illustrating the applicability of the method in low-biomass environments with limited oxygen.
For the current study, the team once again used flow cytometry, staining cells with a chemical called RedoxSensor Green. The intensity at which stained cells light up under a laser correlates with the rate at which those cells are respiring. The DNA of each individual cell was then sequenced to understand the relationship between its activity rate and what it’s programmed to do. This combined technique enables researchers to get a snapshot of the microbial biodiversity and determine which species are the most abundant and active.
"The Single Cell Genomics Center is the world’s first facility capable of large-scale studies of microbial genomes and activities at the ultimate resolution in biology: individual cells,” said Ramunas Stepanauaskas, the director of the center and a co-author on the study. “It is exciting that this unique technology enabled us to shed light on these important ecological processes and truly amazing biological diversity in an environment that is so abundant yet so underexplored.”
To test the ability of microbes to adapt to disruption, which was a new aspect of the project, the team added different amounts of oxygen and laminarin, an abundant carbohydrate produced by brown algae and some phytoplankton common along Maine’s coast.
“By perturbing the system in a manner that has real-world relevance, we can determine the effects of, say, a worm burying into the sediment bringing oxygen or seaweed degrading at the bottom of a mudflat,” Lindsay said.
The findings demonstrate that sulfate-reducers from the Chloroflexota phylum were by far the most active cells in the sediments, though not the most abundant. The researchers also found that adding even small concentrations of oxygen and laminarin stimulated respiration. Chloroflexota cells are metabolically diverse, capable of both using oxygen and other chemical processes. That “genetic flexibility,” Lindsay suggested, may explain why they dominate.
“We went in with the hypothesis that oxygen would poison everything, but it turns out that cells are good at withstanding it and even taking advantage of it,” Lindsay said. “It suggests that the microbial community living in this capricious environment is more resilient than initially thought.”
The findings underscore the incredible range of microorganisms living in these extreme environments — and the value of a cell-by-cell approach for interrogating that diversity.
To that end, the team is currently working to expand their understanding of Maine’s coastal sediments. Using “kickstarter” funding from Bigelow Laboratory, they have begun examining deeper samples from the same study sites using the same experimental design, to observe how the microbial community changes with depth.
At the same time, they are continuing to refine the method for increasingly extreme environments, applying it to sediment collected through the International Ocean Discovery Program more than a kilometer below the Mid-Atlantic ridge, an environment which hosts orders of magnitude fewer cells.
“The advantage of this single-cell approach, enabled by the Center for Aquatic Cytometry and Single Cell Genomics Center, is we can target low-biomass environments where there are so few cells it would be impossible to make a measurement otherwise,” Lindsay said. “My dream is to get a flow cytometer on a mission like NASA’s Europa lander, so we can use this technique to detect possible metabolic activity on other worlds.”
HEY MOM, DAD, I WENT TO UNIVERSITY TO PLAY WITH MUD PIES
Eliza Goodell, an undergraduate intern from Oberlin College, pulls out a sediment core from Edgecomb Eddy.
Credit
Melody Lindsay, Bigelow Laboratory for Ocean Sciences
How does a robot perform as a boss at work? The results of research by Polish scientists published in Cognition, Technology & Work suggest that while robots can command obedience, it is not as strong as in the case of humans. The level of obedience towards them is generally lower than towards human authority figures, and work efficiency under the supervision of a robot is lower. For employers and HR departments, this means the need to take the psychological aspects of implementing robots in the work environment into account - their perception as an authority figure, trust in them, and potential resistance to following orders, says Konrad Maj, PhD, from SWPS University, a psychologist and head of the HumanTech Center for Social and Technological Innovation.
Robot as an authority figure?
The development of robotics has led to a situation in which robots are increasingly found in roles associated with authority, e.g. in education, healthcare or law enforcement. Researchers were intrigued by the extent to which society would accept robots as authority figures. We have shown that people demonstrate a significant level of obedience towards humanoid robots acting as authority figures, although it is slightly lower than towards people (63% vs. 75%). As the experiment has shown, people may exhibit a decrease in motivation towards machines that supervise their work – in our studies, participants performed their assigned tasks more slowly and less effectively under the supervision of a robot. This means that automation does not necessarily increase efficiency if it is not properly planned from a psychological point of view, Maj believes.
Course of the study
The study was carried out in the SWPS University laboratory by scientists from this university: Konrad Maj, PhD, Tomasz Grzyb, PhD, a professor at SWPS University, Professor Dariusz Doliński and Magda Franjo. Participants were invited to the laboratory and randomly assigned to one of two study groups: with the Pepper robot or with a human acting as an experimenter. The task was to change the extensions of computer files. If the participant showed signs of reluctance to continue (e.g., a pause in work lasting more than 10 seconds), the robot or the experimenter used verbal encouragement. The average time to change the extension of one file was shorter under human supervision (23 seconds), while in the groups supervised by a robot this time increased to 82 seconds. The average number of files changed in the first variant was 355, and in the second it was nearly 37 percent less - 224 files.
Human-robot relations
The experiments indicate the complexity of human-robot interactions and the growing role of robots in society. Studies show that anthropomorphic features of robots affect the level of trust and obedience. Robots that are more human-like are perceived as more competent and trustworthy. On the other hand, too much anthropomorphisation can cause the uncanny valley effect, which results in lower trust and comfort in the interaction. Maj points out that there are several explanations for this phenomenon: If a machine has clear human features, but still exhibits various imperfections, this causes a cognitive conflict - we are at a loss as to how to treat it, we do not know how to behave towards something like that. But we can also talk about a conflict of emotions: fascination and admiration mixed with disappointment and fear. On the other hand, supporters of the evolutionary explanation claim that humans are programmed to avoid various pathogens and threats, and a robot that pretends to be a human, but is still not perfect at it, may appear to be a threat. Why? Because it looks like someone sick, disturbed or imbalanced.
At the same time, giving certain human features to a robot can facilitate cooperation with the machine - after all, we are used to working with humans. A robot that looks like a human and communicates like a human simply becomes easy for us to use. But there is also a dark side to this - if we create robots that are very similar to humans, we will stop seeing boundaries. People will start to befriend them, demand granting them various rights, and perhaps even get married to them in the future. In the long run, humanoid robots may create a rift between people. There will also be more misunderstandings and aversion - and this is because robots owned at home will be personalised, always available, empathetic in communication, and understanding. People are not so well-matched, Konrad Maj points out.
References:
Maj, K., Grzyb, T., Dariusz Doliński, & Franjo, M. (2025). Comparing obedience and efficiency in tedious task performance under human and humanoid robot supervision. Cognition Technology & Work. https://doi.org/10.1007/s10111-024-00787-1
(a) Function assessment of kidneys, including renal blood flow (RBF), protein exclusion (EX protein), filtration fraction (FF), and glomerular filtration rate (GRF). Fct: functional; Non Fct: non-functional. (b) Histology, viability, and endothelial morphology of the kidney. (c) Scheme and (d) hematological physiological parameter assessment of post-kidney transplantation after cold storage and vitrification preservation, including serum creatinine, venous potassium, venous pH, and venous lactate. *P < 0.05; NS: not significant.
A review article published in Engineering delves into the crucial field of organ preservation, exploring its history, current techniques, and future prospects. The shortage of donor organs remains a significant global challenge, with only about 10% of the global demand for organ transplantation being met, as stated by the World Health Organization. This shortage is further exacerbated by the limitations of current organ preservation methods.
Currently, the main clinical methods for organ preservation are static cold storage (SCS) and machine perfusion (MP). SCS, which involves storing organs in a preservation solution at low temperatures (usually 4 °C), is simple and cost-effective. It has been widely used, for example, in Japan for kidney preservation. However, it can only maintain the function of organs for a limited time. For kidneys, the preservation time is 12–24 hours; for lungs, 6–8 hours; and for hearts, 4–6 hours. Prolonged SCS can lead to issues such as adenosine triphosphate (ATP) depletion, metabolite accumulation, and subsequent ischemia-reperfusion injury (IRI), which can cause organ damage and transplant failure.
MP, on the other hand, can extend the preservation time. Hypothermic machine perfusion (HMP) can maintain organ function for several days by providing a continuous supply of oxygen and nutrients. Normothermic machine perfusion (NMP), which simulates normal body temperature, has shown superior transplant survival rates in some cases, like in liver transplantation. But it also has its own problems, such as non-anastomotic biliary strictures in liver transplants.
In recent years, cryopreservation techniques have emerged as promising alternatives. Vitrification, in particular, is regarded as a potentially effective long-term organ preservation method. It involves replacing a portion of the water in organs with solutes to form a glass-like state, avoiding ice crystal formation. However, high concentrations of cryoprotective agents (CPAs) are required for vitrification, which can cause toxicity issues in cells. To address this, researchers are exploring various strategies, such as using isochoric preservation to reduce the required concentration of CPAs and developing new rewarming techniques.
The paper also discusses the preservation of different major organs. For kidneys, in addition to SCS and MP, vitrification cryopreservation has shown potential, with successful transplantation of cryopreserved rat kidneys after 100 days. For livers, MP techniques are being developed to address the high discard rate due to IRI. Hearts face challenges in preservation due to high ATP consumption, but MP and vitrification-based methods are being explored. Lungs, currently preserved mainly by SCS for a short time, may benefit from ex vivo lung perfusion (EVLP) and cryopreservation in the future. Intestine preservation is crucial but challenging due to its large bacterial reservoir, and MP techniques are being investigated to improve outcomes.
Significant progress has been made in organ preservation, yet there remains a long journey ahead. Going forward, future research ought to center on devising more efficient preservation strategies, minimizing the toxicity of CPAs, and enhancing rewarming techniques. By doing so, it will be possible to achieve long-term, high-quality organ preservation, thus ultimately resolving the organ shortage issue.
