South Korean Scientists Unlock Secret of Onion’s Chemical Arsenal | Be Korea-savvy

South Korean Scientists Unlock Secret of Onion’s Chemical Arsenal


Onions can actively produce and secrete isoallicin and the lachrymatory factor (LF) while growing, helping protect against external threats. (Image courtesy of Yonhap)

Onions can actively produce and secrete isoallicin and the lachrymatory factor (LF) while growing, helping protect against external threats. (Image courtesy of Yonhap)

JEONJU, Jan. 17 (Korea Bizwire) — A team of South Korean researchers have made a groundbreaking discovery about how onions produce their distinctive pungent compound, isoallicin, revealing it to be part of the vegetable’s natural defense system, the Rural Development Administration (RDA) announced on January 16.

The study marks the first time scientists have identified the presence of the alliinase enzyme in onion cell cytoplasm, demonstrating that isoallicin — known for its antioxidant properties and medicinal benefits — can be produced without cellular damage.

Previously, scientists believed isoallicin was only created when onion cells were damaged, releasing the alliinase enzyme from vacuoles to break down isoalliin in the cytoplasm. The new research shows that alliinase present in the cytoplasm can react with isoalliin directly, producing both isoallicin and the lachrymatory factor (LF) — the compound responsible for making people cry when cutting onions — without cellular injury. 

This discovery suggests that onions can actively produce and secrete these defensive compounds while growing, helping protect against external threats. The finding provides scientific validation for traditional Asian farming practices of intercropping vegetables with onions, garlic, and other allium plants, which have long been observed to reduce crop damage from pathogens and pests.

The research, published in Frontiers in Plant Science, is expected to contribute to the development of environmentally friendly farming techniques and disease-resistant crop varieties. 

“This study not only illuminates the biochemical defense system of onions but also helps us understand similar mechanisms in related crops like green onions and garlic,” said Kwon Soo-jin, director of the RDA’s Genomics Division. “We believe these findings could lead to reducing spoilage in stored onions by clarifying the relationship between isoallicin and storage stability.”

M. H. Lee (mhlee@koreabizwire.com) 

Leave a Reply

Your email address will not be published. Required fields are marked *

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>