Persicaria odorata Persicaria odorata Persicaria odorata, known as rau răm or Vietnamese coriander, is an herb whose leaves are used in Southeast Asian cooking. Other names for this herb include Vietnamese mint, Vietnamese cilantro, Cambodian mint, hot mint, laksa leaf, and praew leaf. Vietnamese coriander is not related to the mints, nor is it in the mint family Lamiaceae, but its general appearance and fragrance are reminiscent of them. "Persicaria" is in the family Polygonaceae, collectively known as "smartweeds" or "pinkweeds". Above all, the leaf is identified with Vietnamese cuisine, where it is commonly eaten fresh in salads (including chicken salad) and
Leaf cold and reduced sunlight by curtailing chlorophyll production. Red anthocyanin pigments are now thought to be produced in the leaf as it dies, possibly to mask the yellow hue left when the chlorophyll is lost—yellow leaves appear to attract herbivores such as aphids. Optical masking of chlorophyll by anthocyanins reduces risk of photo-oxidative damage to leaf cells as they senesce, which otherwise may lower the efficiency of nutrient retrieval from senescing autumn leaves. In the course of evolution, leaves have adapted to different environments in the following ways: The leaf surface is also host to a large variety of microorganisms;