title: Oral single- and repeated-dose toxicity studies on Geranti Bio-Ge yeast, organic germanium fortified yeasts, in rats.
abstract: Single- and 13-week repeated-dose toxicities of Geranti Bio-Ge Yeast, organic germanium fortified yeasts, were investigated in rats. Both sexes of Sprague-Dawley rats were orally administered once at a dose of 2,000 mg/kg in single-dose toxicity or daily for 13 weeks at doses of 500, 1,000 or 2,000 mg/kg in repeated-dose toxicity tests. In single-dose toxicity test to determine dose levels in repeated-dose toxicity study, the body weight gain was suppressed at 2,000 mg/kg, although no death, clinical signs and pathological findings related to the treatment were observed. In repeated-dose toxicity test, there were no clinical signs in animals administered up to 2,000 mg/kg, except one rat died due to a gavage error. In addition, no significant changes in feed consumption and body weight gain were obtained during the treatment period, in spite of week-to-week fluctuation of water consumption. There were no considerable changes in ophthalmoscopy, urinalysis, hematology and serum biochemistry, except a significant decrease in albumin/globulin ratio in males treated with 1,000 mg/kg. In contrast, a significant increase in relative heart weight was observed in both male and female rats treated with a high dose (2,000 mg/kg) of Geranti Bio-Ge Yeast. In microscopic examination, mild lesions were found sporadically in both control and treatment groups in a dose-independent manner. In spite of some alterations in water consumption, serum biochemistry and organ weights, such effects were not considered to include toxicopathological significance, based on the lack of dose-dependency, consistent time-course and gender relationship. Taken together, it is suggested that no observed adverse effect level (NOAEL) of Geranti Bio-Ge Yeast is considered to be over 2,000 mg/kg in rats, and that long-term oral intake in humans might not exert adverse effects.
authors.affiliation: Biotoxtech Co., Ltd., Ochang Scientific and Industrial Complex, Cheongwon, Korea.
authors.forename: Jong-Sung
authors.initials: JS
authors.lastname: Lee
authors.forename: Jong-Il
authors.initials: JI
authors.lastname: Park
authors.forename: Sun-Hee
authors.initials: SH
authors.lastname: Kim
authors.forename: Sun-Hee
authors.initials: SH
authors.lastname: Park
authors.forename: Seong-Kwi
authors.initials: SK
authors.lastname: Kang
authors.forename: Cheol-Beom
authors.initials: CB
authors.lastname: Park
authors.forename: Tsang-Uk
authors.initials: TU
authors.lastname: Sohn
authors.forename: Ja Young
authors.initials: JY
authors.lastname: Jang
authors.forename: Jong-Koo
authors.initials: JK
authors.lastname: Kang
authors.forename: Yun-Bae
authors.initials: YB
authors.lastname: Kim
mesh_terms: D000284:Administration, Oral; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004326:Drinking / Q000187:drug effects; D004334:Drug Administration Schedule; D004435:Eating / Q000187:drug effects; D005260:Female; D005857:Germanium; D006321:Heart / Q000187:drug effects / Q000502:physiology; D008297:Male; D009929:Organ Size / Q000187:drug effects; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000633:toxicity*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012737:Sex Factors; D015003:Yeasts
chemical_list: D009942:Organometallic Compounds; D005857:Germanium