Abstract: Riboflavin is effectively obtained by culturing in a medium (1) a purine-requiring revertant derived from a riboflavin-producing yeast which belongs to the genus Saccharomyces and has a purine requirement or (2) a riboflavin-producing yeast which belongs to the genus Saccharomyces and is resistant to ammonium ion, and collecting the produced riboflavin.

Abstract: Strains of yeast of the species Candida famata are disclosed which can produce 10 grams of riboflavin per liter in 6 days, and in particular, strains identified by ATCC Accession Nos. 20849 and 20850. Riboflavin yields of more than 20 grams per liter in 200 hours have been achieved. Strains of the present invention have increased sensitivity to iron inhibition of flavinogenesis and have enhanced riboflavin production per cell at increased iron concentrations in the fermentation medium.

Abstract: The present invention is concerned with the use of aniline derivatives of the general formula: ##STR1## wherein R.sub.1 is a hydrogen atom or a lower alkyl or aryl radical, R.sub.2 is a hydrogen atom or a lower alkyl radical which can be substituted by hydroxyl, amino, carboxyl, lower alkoxycarbonyl, lower alkanoylamido, aryl lower alkyl or aryl or by a group of the structure: ##STR2## in which R.sub.5 and R.sub.6 have the meanings given hereinafter, R.sub.3 is a hydrogen or halogen atom or a carboxyl group, R.sub.4 and R'.sub.4, which can be the same or different, are hydrogen or halogen atoms, carboxyl groups or lower alkoxy radicals or lower alkyl radicals which are preferably in the m-position and R.sub.1 and R.sub.4 or R.sub.2 and R.sub.4 or R.sub.4 and R'.sub.4, when the two substituents are ortho to one another, can together form a saturated or unsaturated hydrocarbon chain containing 2 to 6 carbon atoms which can be substituted by hydroxyl or oxo groups, R.sub.

Abstract: The practice of this invention provides a photosensitive member which comprises a charge generating layer, and a plasma-polymerized layer, wherein said plasma-polymerized layer having an infrared absorption spectrum of a ratio of coefficients of absorptivities attributed to methyl group (--CH.sub.3) to those of methylene group (--CH.sub.2 --), and is a coefficient of absorptivity attributed to methylene group (--CH.sub.2 --) at about 2925 cm.sup.-1. The photosensitive member obtained thereby is excellent in charge-transporting property and chargeability and, moreover, exhibits advantages in corona resistance and resistances to acids, moisture and heat and also in physical properties such as stiffness.

Abstract: Riboflavin is obtained directly from the culture in a high yield by cultivating a riboflavin-producing microorganism in a medium using a lower (C.sub.1 to C.sub.4) aliphatic compound, separating riboflavin contained in the culture in the form of heated aqueous solution from solid matters, and crystallizing riboflavin from the heated aqueous solution.Riboflavin is also prepared in a high yield by cultivating a riboflavin-producing yeast belonging to the genus Saccharomyces which has purine requirements and/or resistance to 3-amino-1,2,4-triazole in a medium and collecting riboflavin formed and accumulated in the medium.Moreover, riboflavin is prepared in a high yield even in the presence of iron ions by preliminarily cultivating in liquid a riboflavin-producing yeast belonging to the genus Saccharomyces and then cultivating it in a riboflavin-producing medium containing zinc ions.

Abstract: Riboflavin is recovered from fermentation broth by diluting the broth with a predetermined quantity of water, centrifuging the diluted broth to form a sludge, resuspending the sludge with a predetermined quantity of water, and centrifuging the resuspended sludge to yield a product usuable directly as an animal feed supplement or suitable for further purification for pharmaceutical use. Optionally the broth or resuspended sludge is treated with an enzyme before centrifugation.