Molds grow on textiles dyed by vegetable dyestuffs in warm rainy season. A kind of Penicillium is isolated from a musty aqueous extract of Punica granatum L. The penicillium actively grew, and formed spores, on a textiles dyed by vegetable dyestuffs of three kinds of plant tissues, viz., barks of Myrica rubra SIEB. & Zucc., fruits of Gardenia grandiflora MAKINO, and fruits of Punica granatum. This organism, also, grew in aqueous extract from the plant tissues mentioned above. It grew only a little on the textiles and aqueous extract from wood of Casesalpinia sappan L., however. The organism could grew only to whitish colony and not form spores in that extract. The causes of them were investigated. It becomes bow evident that the quantity of thiamine, riboflavin, and other growth factors were insufficient for growth and spore-formation of the organism in aqueous extract of C. sappan.

It is frequently found that molds grow in preserved aqueous extract of vegetable dyestuffs. These molds grow even on dyeing textiles at rainy season. There are, however, some differences in growth-activity of the mold owing to the nature of vegetable dyestuffs. The mold fairly grows on dyeing textile by aqueous extract of Gardenia jasminoides ELLIS f. grandiflora MAKINO, Punica granatum L., and Myrica rubra SIEB. et Zucc. On dyeing cloth by Caesalpinia sappan L., however, mold grows a little. In this report the authors attend to find some conditions for growth of mold on vegetable dyestuffs.