Posts Tagged ‘plant’

By Yasemin Saplakoglu

Drinking a cup of tea or eating a handful of berries a day may help protect against heart disease, a new study suggests.

The research, presented November 10 at the American Heart Association’s Scientific Sessions annual meeting, found that daily consumption of small amounts of flavonoids — compounds found in berries, tea, chocolate, wine and many other fruits and plants — was associated with a lower risk of heart disease.

This association (which is not to be confused with a cause-and-effect finding) is not new; previous research has also found a link between flavonoids and heart disease risk. But the new study — one of the largest done to date — adds stronger evidence to the idea that flavonoids may protect the heart, said co-lead study author Nicola Bondonno, a postdoctoral researcher at the School of Biomedical Science at the University of Western Australia.

In the study, Bondonno and her team analyzed data from nearly 53,000 people who had participated in the long-running Danish Diet, Cancer and Health Study, which began in the 1990s. At the beginning of that study, participants filled out a questionnaire with information about what types of foods they ate and how often they ate them. The researchers then tracked the participants’ health for more than two decades.

After a 23-year follow-up period, around 12,000 of the participants had developed some sort of heart condition.

The researchers found that people who reported eating around 500 milligrams or more of flavonoids daily had a lower risk of developing ischemic heart disease (where the heart’s major blood vessels are narrowed, reducing blood flow to the heart), stroke and peripheral artery disease (where blood vessels in the body are narrowed, reducing blood flow throughout the body). This association was the greatest for the latter, the researchers found.

Bondonno noted that 500 mg of flavonoids is “very easy to eat in one day.” You would get that amount of flavonoids from “a cup of tea, a handful of blueberries, maybe some broccoli,” she said. They also found that, on average, it didn’t make too much of a difference how much more flavonoids healthy people consumed once they passed the 500 mg/day threshold.

The reason flavonoids could have a protective role against heart disease is because of their anti-inflammatory properties, Bondonno told Live Science. Inflammation is a risk factor for heart disease, she said.

The researchers noted that the association between flavonoids and reduced heart disease risk varied for different groups of people. The link between flavonoids and reduced risk of heart disease in smokers, for example, wasn’t observed at 500 mg of flavonoids a day; rather, smokers needed to eat more flavonoids for the link to be apparent. Similar results were seen in people who drank alcohol and in men. However, it was in these three groups that the researchers found that flavonoid intake was associated with the greatest reduction in risk.

In their analysis, Bondonno and her team made sure to take people’s whole diets into consideration, because people who tend to eat lots of fruits and vegetables (and in turn, consume a lot of flavonoids), tend to have better diets in general, eating more fiber and fish and less processed food, which are all “associated with heart disease,” Bondonno said. When they adjusted for these diets in their report, they found that the association between flavonoid intake and reduced heart disease risk was still there, but a bit weaker. In other words, flavonoids may not play as big a role in heart disease risk as a healthy diet would in general.

Further, the study was conducted only in Danish people, and though these results shouldn’t be extrapolated, “these kinds of associations have been seen in other populations,” Bondonno said.

The findings have not yet been published in a peer-reviewed journal.

https://www.livescience.com/64060-flavonoids-heart-health.html

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by PETER DOCKRILL

When somebody mentions anaesthetics, we probably think straight away of pain relief, but there’s a lot more going on in these complex chemical compounds than the simple negation of discomfort.

While there’s a range of chemicals that can induce anaesthesia in humans, just how these unrelated compounds trigger a lack of consciousness remains somewhat unclear.

And the mystery deepens when you consider it isn’t only animals that are affected by anaesthetics – plants are, too.

Humans in ancient societies were using things like herbs for various sedative purposes thousands of years ago, but the roots of modern anaesthesia began around the mid-19th century, when physicians began administering diethyl ether to patients during surgical procedures.

It was only a few decades later that scientists realised plants were similarly affected by ether, leading French physiologist Claude Bernard to conclude plants and animals shared a common biological essence that could be disrupted by anaesthetics.

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A century and a half later, scientists are still investigating this strange commonality – basically by slipping plants the mickey and seeing what it does to them.

In a new study by Japanese and European researchers, the team filmed a number of plants that exhibit the phenomenon of rapid plant movement to see what kinds of anaesthetic chemicals affected them.

The sensitive plant (Mimosa pudica) usually closes its leaves in response to touch stimuli; but when exposed to diethyl ether, the dosed-up plants completely lost this response, becoming motionless, with the movement response only returning to normal after 7 hours.

In a separate experiment with the sensitive plants, a lidocaine solution also immobilised the leaves.

Similarly, the Venus flytrap (Dionaea muscipula) lost its ability to close its trap when exposed to diethyl ether – despite repeated prongings by the researchers – but the mechanism recovered in just 15 minutes.

Another carnivorous plant, Cape sundew (Drosera capensis), captures prey via sticky tentacles on its leaves, but experiments showed they lost the ability to bend their leaves and tentacles when exposed to the ether.

As for why plants are incapacitated by these chemicals, the researchers hypothesise it is to do with the inhibition of action potentials, preventing electrical impulses that help plants’ biological systems function.

“[B]ioelectricity and action potentials animate not only humans and animals but also plants,” the researchers explain.

“That animals/humans and also plants are animated via action potentials is of great importance for our ultimate understanding of the elusive nature of plant movements and plant-specific cognition/intelligence based plant behaviour.”

Ultimately, the team thinks these similarities between plant and animal reactions to anaesthetic compounds could lead to future research where plants might function as a substitute model or test system to explore human anaesthesia – something scientists are still pretty uncertain about.

It’s not easy being green, perhaps, but at least they shouldn’t feel any pain.

The findings are reported in Annals of Botany.

https://www.sciencealert.com/plants-respond-anaesthetics-weird-movement-action-brain

https_blogs-images.forbes.comandreamorrisfiles201809Blazes-of-Lights-in-Plants-1200x606

When humans are attacked, sensory cells transmit signals through our nervous system, spitting out the neurotransmitter–glutamate. Glutamate stimulates our brain’s amygdala and hypothalamus. This triggers the stress hormone–adrenaline–that jolts us into fight or flight mode. Plants don’t have neurotransmitters. They don’t have nervous systems. The don’t have brains. But now, for the first time, scientists are able to observe how a plant responds to an attack with vivid real-time imagery that illuminates the remarkable differences and similarities between plants and humans. Same substance, same results, different anatomy. In the video below, a plant gets chomped on by a caterpillar. At the site of the wound, the plant spills out glutamate–the same chemical as our glutamate neurotransmitter, but not a neurotransmitter. This triggers a calcium wave throughout the plant body, stimulating a plant stress hormone that prepares it for the vegetal version of fight or flight.

To observe what’s happening, scientists sampled a gene from jellyfish that makes them glow green. Then they genetically modified plants to produce a protein that fluoresces around calcium. The results are a blazing calcium wave that undulates through the plant vascular system when it gets bit.

“[For] the first time, it’s been shown that glutamate leakage at a wound site triggers a system-wide wound response, and the first time we’ve been able to visualize this process happening ,” says Simon Gilroy, professor of botany at the Gilroy Lab at the University of Wisconsin-Madison, and senior author on the paper out today in the journal Science.

An incidental breakthrough

The discovery came about via “the classic opportunistic randomness of science,” says Gilroy. The lab wasn’t investigating plant wounds. It was looking at how plants take in and assimilate information. One day, postdoctoral researcher and first author on the paper, Masatsugu Toyota, approached the team: “‘You have to see this. This is amazing,” he said.’ It just played out in front of us,” says Gilroy.

https://www.forbes.com/sites/andreamorris/2018/09/13/blazes-of-light-show-plants-response-to-being-eaten-video/#125a991337cc

by RUSSELL MCLENDON

Rip Van Winkle, the titular ne’er-do-well of Washington Irving’s 1819 short story, famously spent 20 years napping in a forest. This lengthy slumber, apparently triggered by ghost liquor, caused Van Winkle to sleep through the American Revolutionary War.

Nearly two centuries later, scientists are shedding light on plants that do something similar in real life. A surprisingly diverse mix of plants around the world can live dormant underground for up to 20 years, researchers report in the journal Ecology Letters, a strategy that allows the plants to survive hard times by simply napping until things get better.

At least 114 species from 24 plant families are capable of this trick, in which a plant abandons photosynthesis to focus on survival in the soil. It’s a way for plants to hedge their bets, the study’s authors explain, by accepting certain short-term hardships — like missed opportunities to grow and reproduce — for the longer-term benefits of avoiding mortal dangers on the surface.

“It would seem to be paradoxical that plants would evolve this behavior, because being underground means they cannot photosynthesize, flower or reproduce,” says co-author Michael Hutchings, an ecology professor at the University of Sussex, in a statement. “And yet this study has shown that many plants in a large number of species frequently exhibit prolonged dormancy.”

So how do these Rip Van Winkle plants survive for up to 20 years without sunlight? Many species have found other ways to endure dormancy, Hutchings says, especially “by evolving mechanisms enabling them to obtain carbohydrates and nutrients from soil-based fungal associates.” Befriending soil fungi, he adds, “allows them to survive and even thrive during dormant periods.”

This strategy is used by many orchid species (including the lady’s slipper orchids pictured above), along with a wide variety of other plant types. It typically occurs in only part of a population or species during any given year, the researchers note, so the broader population can keep growing and reproducing while the designated survivors wait underground as backup.

https://www.mnn.com/earth-matters/wilderness-resources/blogs/rip-van-winkle-plants-can-hide-underground-20-years

by Alanna Ketler

An estimated 400,000 flowering plant species exist in the world, and, understandably, it can be difficult to keep track. The vast majority of us can only recognize and name a handful of plants, even if we would like it to be otherwise. If you would like to sharpen your knowledge in the wonderful realm of plant species, I have some good news for you. Like everything else: there’s an app for that.

If you ever walk by a specific plant that you would like to identify, or you have extensive knowledge about plant species that you would like to share, then the PlantNet app is for you. Available for iPhone and Android devices, it is essentially the Shazam for plants. It’s pretty awesome to consider what technology is capable of these days.

The app works by collecting data from a large social network which uploads pictures and information about plants. Scientists from four French research organizations including Cirad, IRA, Inria/IRD, and the Tela Botanica Network developed the app.

The app features visualization software which recognizes many plant species, provided they have been illustrated well enough in the botanical reference base. PlantNet currently works on more than 4,100 species of wild flora of the French territory, and the species list is provided through the application. The number of species included and images used by the application grows as more users contribute.

While only a small percentage of plant species can be identified so far, the more users who join, and the more participants from different countries become involved, the more diverse this app will become. So if this is something that interests you, get the app and start contributing today.

While at the moment it doesn’t focus on edibles, this app lays the frame work for herb collecting and identifying plants in nature that could either be dangerous to you or that you would love to learn more about. The average person these days is enjoying a greater appreciation for nature this app can help them outfit their home and living space with plants they love.

In the future, an edible database could help foragers pick from the wild spread nature has to offer. Not only are wild sources of plants and herbs cleaner and free of pesticides, but they also can be picked fresher and be more nutritious.

At the same time, this app is inevitably going to get people out in nature more as now they can walk about trails and nature with a keen curiosity to learn more about what’s around them.

http://www.collective-evolution.com/2016/03/10/the-shazam-for-plants-will-identify-any-plant-from-a-picture/