A research team led by Japanese high school and university students has discovered that mulberry leaves contain biogenic minerals known as opal phytoliths, rigid microscopic structures that persist after death and can have forensic value.
They are found in a range of plants. Archaeologists, for example, monitor opal phytoliths because they can provide clues as to where rice was cultivated.
The findings were published in the February edition of international botanical journal Flora.
The students and the teachers who supported them say it is the first time opal phytoliths have been found in mulberry leaves.
The team included Otoha Tsutsui, a sophomore at Waseda University, and Rei Sakamoto, a freshman at the university, who were students at Waseda University Honjo Senior High School at the time of their research.
Mulberry is eaten by silkworms. Assuming that opal phytoliths promote silkworms' appetite, the finding may lead to a study to find ways to make silkworms eat more mulberry leaves and increase silk production, the university said on its website.
Opal phytoliths are valued in research fields as they may be preserved even after plants die and decay. They have "attracted interest in various research fields of biology, archaeology, ecology, and technology," according to the team's report published in English in the journal.
Researchers have so far found the structures — also known as plant opals — in rice and other plants.
