SPAGYRIC HERBALISM

Blighia sapida: A tropical fruit with antimicrobial properties

by American Society for Microbiology

B. sapida fruit, showing peach colored arils covering dark oval seeds. 

Source: Wikimedia Commons

Antimicrobial resistance (AMR) remains 1 of the top 3 global public health challenges facing humanity. Every year, 70,000 people die globally from AMR, and the threat is exacerbated by the fact that we have moved from the era of excess antibiotics to one where only a few antibiotics are considered innovative by World Health Organization (WHO) standards.

The African continent has the highest rate of AMR-related mortality, with Sub-Saharan Africa having the highest mortality rate of 23.5 deaths per 100,000 people in 2019. This is, in part, a result of poverty and fewer regulations on antibiotic use, thereby putting a limit on the solutions that can be offered.

When it comes to identifying new antimicrobials to combat AMR effectively, much can be learned from ethnobotany, an approach that has been used in developing countries for decades, which looks at the practical and medicinal uses of indigenous plants.

Blighia sapida is one plant that shows excellent antimicrobial activity and compares favorably with standard antibiotics, like streptomycin. It is ubiquitous in Africa, easily accessible and offers cost-effective extracts that can be used in the formulation of antimicrobials. Here we take a closer look at what is known about B. sapida's phytochemicals, highlight key areas for further research and introduce a few other plants that have shown activity against pathogens.

B. sapida in traditional medicine

Africa has about 5,000 species of plants that are used for medicine, some of which are antimicrobials. One of these plants is B. sapida, a plant that is ubiquitous in West Africa and can be easily cultivated at low cost. Called by many names in different parts of the continent (Okpu, Isin, Isin, akee apple, etc.), B. sapida is a gem that is used in many industries, including construction. However, its use in medicine in these developing countries is distinct.

The plant extracts have demonstrated in vitro and in vivo antidiarrheal, anticancer, hypoglycemic and antioxidant activities. B. sapida has been used to treat oedema, dysentery and diarrhea, fever, ulcers, yaws, intercostal pain, epilepsy and yellow fever. It has also demonstrated effectiveness in treating gonorrhea, psychosis, stomach ache, rheumatism, hernia, constipation and even cancer. Unripened B. sapida is poisonous for consumption, as it contains a high concentration of hypoglycin A. However, the arils (an additional outgrowth that covers, or partially covers, B. sapida seeds) lose toxicity as the fruit ripens, making the arils of mature ackee safe for consumption.

B. sapida also has antimicrobial properties. For example, the leaf extract of B. sapida showed in vivo antiplasmodial activity—reducing the development of Plasmodium berghei, which causes malaria in rodents. Furthermore, methanolic extract of arils of the plant inhibited in vitro growth of Klebsiella pneumoniae and Staphylococcus aureus.

In another study, B. sapida extract exhibited varying degrees of in vitro activity against S. aureus, Bacillus subtilis, Salmonella Typhi and Streptococcus pneumoniae, as well as 2 strains of gram-negative bacteria, Escherichia coli and K. pneumoniae. Notably, the stem bark and leaf extract of the plant compare favorably well with streptomycin and have low minimum inhibitory concentration and minimum bactericidal concentration in most cases. These studies provide evidence that B. sapida could serve as a drug to treat infections caused by any of these pathogens. But what exactly makes the plant active against these pathogens.

Why B. sapida works

Medicinal plants are the most common traditional medicine used in Africa because of their ease of accessibility, as well as the traditional healer's understanding of the patient's immediate environment. The tropical and subtropical climate in Africa can be hostile and facilitate adaptation of secondary metabolites, which turn out to be beneficial to human health and accumulate more chemopreventive substances than plants in the northern hemisphere.

Studies have shown that extracts from plants could have various inhibitory effects on bacteria, fungi, viruses, protozoa and even parasites due to a synergistic effect of their active ingredients. Ackee's many phytochemicals, including saponins, tannins, flavonoids and alkaloids, have antimicrobial properties and seem to be the reason for the plant's medicinal effectiveness.

For example, saponins cause lysis of bacterial cells; tannins interfere with the metabolism of the cell, eventually causing destruction; flavonoids inhibit nucleic acid synthesis and phenol suppresses the formation of bacterial biofilm. Alkaloids also disrupt bacterial cell membranes, affect DNA function and inhibit protein synthesis.

This synergy is especially important because, while bacteria could easily develop resistance to a particular mechanism of action, the fact that these plants resist microbes using the combined effect of multiple bioactive compounds ultimately reduces the possibility of resistance.

Future outlook of B. sapida

Given the many applications of B. sapida for treating various diseases, and its activity against many human pathogens, several researchers advise further studies. In order to verify that B. sapida is a viable and safe product for use in the formulation of new antibiotics against human pathogens, scientists must assess the toxicity of B. sapida to determine potential side effects, safe dosage, toxic threshold and risk for comprehensive regulatory compliance.

Researchers must also characterize the chemical composition of B. sapida using complex analyses to identify the bioactive components. There is an inadequacy in the characterization of the chemical composition of medicinal plants in Nigeria; only a few of the plants' bioactive components have been analyzed using complex analyses like high-performance liquid chromatography (HPLC).

The few existing studies on B. sapida show great prospect, but additional funding is needed to understand the underlying synergy of phytochemicals present in this medicinal plant (as well as others). Such chemical characterizations are needed to validate the medicinal claims associated with B. sapida.

Provided by American Society for Microbiology Scientists develop green method for producing bactericidal copper oxide nanoparticles from noni plant

ARCHAEOLOGY

Stone Tools Found in Ukraine May Be the Oldest Evidence of Early Humans in Europe

The 1.4-million-year-old rocks may have belonged to Homo erectus, and they shed light on migrations of human ancestors, a new study suggests


Will Sullivan
Daily Correspondent

March 7, 2024 

A view of the Korolevo archaeological site. Researchers used the decay of isotopes in rocks dug up from the site to determine the age of the stone tools. 

Roman Garba


Stone tools dug up in western Ukraine date to about 1.4 million years ago, making them the earliest evidence of human presence in Europe, researchers report Wednesday in the journal Nature. While modern humans likely didn’t make the tools, researchers suggest the closely related species Homo erectus did.

“Confidently dated early hominin sites are scarce in Europe,” Toshiyuki Fujioka, a geochronologist at the National Research Center on Human Evolution in Spain who did not contribute to the findings, tells Live Science’s Charles Q. Choi. “This study provides a much-needed, reliably dated chronological site to add fuel to our discussion on ancient human migration.”

The tools, created from volcanic rock, put a new pin in the map of human ancestors’ migrations on the continent. Researchers had previously found evidence of early humans in Georgia, at the border of Europe and Asia, that dates to 1.8 million years ago. And in France and Spain, the first evidence of hominins dates to 1.1 million to 1.2 million years ago. The new artifacts—which were found between these two other sites—support the theory that human ancestors spread from east to west into Europe at this time, the study authors write.

One of the stone tools, thought to be 1.4 million years old, found at the Korolevo site in Ukraine. 

Roman Garba

“Until now, there was no strong evidence for an east-to-west migration,” Roman Garba, first author of the study and an archaeologist at the Czech Academy of Sciences, says to Nature News’ Giorgia Guglielmi. “Now we have it.”

The first human ancestors expanded out of Africa around 2 million years ago. They reached southern Eurasia at least 1.75 million years ago and southeast Asia around 1.6 million years ago, per the Australian Museum.

Archaeologists found the stone tools at a site called Korolevo in western Ukraine, near the country’s modern borders with Romania and Hungary, according to a statement from the Czech Academy of Sciences. Scientists have been digging at the site since the 1970s and found 33 artifacts in its oldest layer of sediment, which hadn’t been dated, writes Science’s Bridget Alex.

But the team determined the age of this layer, which contained the stone tools, using a technique called cosmogenic nuclide dating. When cosmic rays, or high-energy space radiation, hit exposed rock on Earth’s surface, they can create radioactive isotopes. These isotopes decay at known rates once they are buried underground, serving as a clock researchers can use to determine when the tools were buried. The team measured isotopes in quartz to date the soil to 1.4 million years old.

Based on this age, researchers hypothesize the tools were made by Homo erectus, a hominin species that lived between 1.89 million and 110,000 years ago—the earliest humans with body proportions similar to those of modern humans. But without fossil remains to confirm H. erectus was at the site, “we can’t be sure,” Garba tells Christina Larson of the Associated Press (AP).

The dates “appear to be highly reliable,” Véronique Michel, a geochronologist for the National Center for Scientific Research in France who did not contribute to the findings, tells Science.

“I think this new paper nicely fills a gaping hole in our current knowledge of early human migrations into Europe,” Richard Roberts, a human evolution researcher at the University of Wollongong in Australia who was not involved in the research, says to Live Science. “More well-dated sites are needed to increase our confidence in when Europe was first colonized and by which routes.”

Stone tools dated in the new paper were likely made by Homo erectus, scientists say. Garba, R. et al. "East-to-west human dispersal into Europe 1.4 million years ago." Nature (2024)

Fabio Parenti, an archaeologist at the Federal University of Paraná in Brazil who did not contribute to the findings, tells Science that the study is “quite weak”—the artifacts in the paper are badly described, he tells the publication, and the dates’ error ranges overlap with more recent sites in Europe.


The Korolevo site hasn’t been damaged since Russia’s invasion of Ukraine, but it has become overgrown with vegetation, says Garba, who visited the site last year for the first time since the 2022 invasion, to Nature News.

Few scientists can currently conduct field research in Ukraine due to travel restrictions or because they have fled the country, Vitaly Usyk, a co-author of the study and archaeologist affiliated with the National Academy of Sciences of Ukraine, says to Nature News.

Patagonia cave paintings are earliest found in South America

Argentine scientists discover oldest cave art in South America in a Patagonian cave

Miguel Lo Bianco
Thu, March 7, 2024

By Miguel Lo Bianco

NEUQUEN, Argentina (Reuters) - Archaeologists have discovered the earliest dated cave paintings in South America in Argentine Patagonia, dating back 8,200 years.

The 895 paintings were found by Argentine and Chilean archaeologists in the Huenul 1 cave, a 630 square meter rock shelter located in the province of Neuquen, some 1,100 kilometers (684 miles) southwest of the capital Buenos Aires.

"We were able to date four black peniform patterns that were drawn in charcoal. These proved to be the earliest direct dating of cave paintings in South America," said Dr. Guadalupe Romero Villanueva, author of the research published in the Science Advances journal.

The Argentinean archaeologist said the discovery indicates that the production of cave art began in the Huenul cave about 8,000 years ago and that the practice of painting the particular pattern seen in the cave was sustained for a period of at least 3,000 years.

The discovery provides evidence of the artistic ability and cultural transmission of the hunter-gatherer societies which inhabited the region during the middle Holocene, a period roughly from 7,000 to 5,000 years ago, and reveals the socioecological resilience to climate, as well as serving as a means of communication between scattered populations.

"We believe these images in particular were part of a resilient response of the mobile hunter-gatherer groups that occupied this cave and the desert environments of northern Patagonia to the climatic challenge of a period of extreme dryness that occurred during the middle Holocene," said Romero Villanueva, a researcher at the National Council for Scientific and Technical Research of Argentina.

Villanueva said there are other places in South America that could have older cave paintings, but which only have relative dating, like Argentina's Cueva de las Manos, with cave paintings dating back 9,500 years.

(Reporting by Miguel Lo Bianco; Writing by Steven Grattan; Editing by Stephen Coates)

Archaeologists explore ‘geophysical mysteries’ of graveyard in new dig at Sutton Hoo


The National Trust is working with TV show Time Team on the two-year research project

Sam Russell

The steamship Lady Alice Kenlis on the National Trust’s Sutton Hoo estate
(James O. Davies/Historic England/PA Wire)

A new dig is to be carried out at Sutton Hoo, which is known for the Anglo-Saxon ship burial discovered in 1939.

Archaeologists hope to build a greater understanding of the Suffolk site and learn more about an Anglo-Saxon cemetery which was discovered in 2000 during construction of a visitor centre.

The National Trust is working with TV and online show Time Team on the two-year research project, with a dig planned to begin June.

The conservation charity said the project will build on work by Time Team in 2021 and 2022, when ground penetrating radar surveys were carried out of the Royal Burial Ground and Garden Field.

Angus Wainwright, regional archaeologist for the National Trust, said: “Time Team’s geophysical survey identified several mysterious features in Garden Field.

“We want to determine if they are archaeology or geological features.

“To do this we are carefully planning for an archaeological dig in June.

“Garden Field has an extraordinary amount of archaeology in it, from prehistoric fields and possible burial mounds through to Roman settlements and an Anglo-Saxon cemetery, but who knows what else may be hidden there.


“We know from previous work in this field, it’s likely we will find prehistoric flint tools and fragments of Anglo-Saxon objects from burials scattered through the plough soil, but working out what the mysterious geophysical anomalies are will be our focus.

“We hope to find evidence of the deep-time prehistory of Sutton Hoo and perhaps more information about the Anglo-Saxon cemetery, which we first discovered in 2000 when we were building the visitor centre.

“The approach will be painstaking, recording all the finds in 3D from the ground surface, down through the plough soil until we reach the undisturbed archaeology.”

Tony Robinson and Dr Helen Geake at Sutton Hoo in Suffolk
(Time Team/PA Wire)

The ship burial is thought to have been the final resting place of King Raedwald, who ruled East Anglia in the seventh century.


Mr Wainwright said the 1939 discovery “not only stunned the archaeological world but set the scene for further exploration”.

“Later archaeological campaigns at Sutton Hoo helped solve mysteries left by the original dig and revealed more about life in the Anglo-Saxon kingdom of East Anglia,” he said.

“We can’t wait to see what this next chapter will bring.”

Members of the 1980s archaeological team who carried out a dig on the Royal Burial Ground will be involved in the latest project.

Tim Taylor, Time Team’s series producer and creator, said: “We are incredibly thrilled to expand our relationship with Sutton Hoo, delving deeper into the history of one of Britain’s most iconic sites.

“The story of Sutton Hoo has captured the world’s imagination, as we can see by the success of the award-winning film The Dig, and we hope to reveal yet another exciting chapter.”

Lady Alice Kenlis on the National Trust’s Sutton Hoo estate in Suffolk
(James O. Davies/Historic England/PA Wire)

Time Team expert Helen Geake said: “It feels so exciting that we can uncover a new area, a new part of the landscape.

“It’s a tantalising piece of the jigsaw puzzle that we’ve always known a bit about, but to be able to find something new and tangible would be truly amazing.”

Time Team will document the investigation, culminating in a documentary presented by Sir Tony Robinson.

Sir Tony said: “In all my years exploring archaeology, I never, ever thought that I would get a chance to be involved with an excavation of Sutton Hoo – that is so exciting.”

The National Trust will be working with archaeology volunteers to help support the project and there will be opportunities for visitors to see archaeology in action when the dig takes place.

Lavish Tomb Reveals Spine-Chilling Ritual of Ancient Coclé Culture

HUMANS08 March 2024

ByCARLY CASSELLA

Gold plate from Coclé tomb. (Panama Ministry of Culture)

The afterlife could be a lonely place with your loved ones staying behind in the land of the living.

In the ancient Coclé culture, which existed in Panama between 200 BCE and 1550 CE, elite individuals didn't have to worry about eternal solitude. The tomb of a young Coclé lord from roughly 1,200 years ago reveals the spine-chilling reality for any surrounding company when a powerful leader dies.

In a specific section of the Rio Grande Valley, archaeological evidence from ancient cemeteries suggests that Coclé chiefs and nobility were sometimes buried alongside their companions, such as their favorite wives or servants, who were sacrificed as part of the funeral.

The tomb of the Coclé lord, which was originally found in 2011 in El Caño Archaeological Park, contains piles of gold artifacts and the bones of up to 31 other people.

Excavation of the elite tomb in Panama. (Panama Ministry of Culture)

The elite individual's own body was interred face down on top of a female body, which experts say was a common tradition in the culture.

Over the years, archaeologists unearthing the ancient enclosed cemeteries of El Caño and a nearby spot called Sitio Conte have found numerous tombs that hold more than one body. But the burial of the young lord in El Caño around 750 CE is especially lavish.

Gold artifact with animal-like body found in the ancient tomb of a Coclé lord in Panama. (Panama Ministry of Culture)

The luxury items found in his tomb probably had spiritual significance. Among shards and shards of pottery lie two belts made of gold beads, four bracelets, two earrings in the shape of a man and a woman, an earring in the shape of a crocodile, a beaded necklace, five earrings made from sperm whale teeth with gold covers, two gold plates, two bells, skirts and bracelets made of dog teeth, and a set of flutes made from bone.

Gold figurine from the tomb of an ancient Coclé lord in Panama. (Panama Ministry of Culture)

The excavation of the site is not yet complete, which means the numbers of individuals buried in that one single tomb could still change. The range sits somewhere between 8 and 32, but it's hard to say for sure which bones go with which person without genetic analysis.

A gold plate excavated from the ancient tomb of an elite Coclé leader in Panama.

Julia Mayo, leader of the archaeological project, and her team have shared some initial findings and photographs of the tomb on the website for Panama's Ministry of Culture.

With further analysis, the archaeologists hope to uncover cultural, spiritual, and political elements of the mysterious Coclé culture and their hierarchical ways of life.