Gregory, Kenneth F. (Ontario Agricultural College, Guelph, Ontario, Canada), and Jay C. C. Huang. Tyrosinase inheritance in Streptomyces scabies. II. Induction of tyrosinase deficiency by acridine dyes. J. Bacteriol. 87:1287-1294. 1964.-Growth in minimal medium containing 1 mug of acriflavine per ml resulted in a large increase (up to 62%) in the frequency of tyrosinase-deficient (tye(-)) mutan...

Tyrosinase, a key copper-containing enzyme involved in melanin biosynthesis, is closely associated with hyperpigmentation disorders, cancer, and neurodegenerative diseases, and as such, it is an essential target in medicine and cosmetics. Known tyrosinase inhibitors possess adverse side effects, and there are no safety regulations; therefore, it is necessary to develop new inhibitors with fewer...

OBJECTIVE Topical administration of latanoprost sometimes induces gradual iris darkening. The present study was undertaken to determine if latanoprost can increase transcription of the gene for tyrosinase, an important enzyme in the biosynthesis of melanin. Results from brown, hazel, and blue irides were compared. METHODS Iris tissue was isolated from 30 pairs of postmortem human donor eyes, ...

Serum tyrosinase activity in many persons with metastatic diseases was found to be significantly higher than activity in normal persons. The highest activity was observed in melanoma and breast carcinoma. The electrophoretic patterns of serum tyrosinase, resolved by electrophoresis of a serum tyrosinase fraction followed by incubation of the gel sample with L-dopa, and represented as sets of RF...

The inhibitory effects of α-arbutin, β-arbutin, and kojic acid on melanogenesis, tyrosinase activity, and tyrosinase protein expression in mouse melanoma cells (B16-4A5) and human melanoma cells (HMV‐II) were directly compared. β-Arbutin showed a stronger inhibitory effect on melanogenesis and tyrosinase expression in B16-4A5 cells than α-arbutin and kojic acid. Kojic acid showed a stronger inh...

Cutaneous hyperpigmentation is a common disorder due to excess melanin production by the enzyme tyrosinase. The gold standard for treatment is hydroquinone (HQ), which reduces pigmentation through its toxicity to melanocytes rather than via tyrosinase inhibition. We screened an internal library for oligopeptides that inhibited both mushroom and human tyrosinase but showed no cytotoxicity to hum...

In therapeutic interventions associated with melanin hyperpigmentation, tyrosinase is regarded as a target enzyme as it catalyzes the rate-limiting steps in mammalian melanogenesis. Since many known agents have been proven to be toxic, there has been increasing impetus to identify alternative tyrosinase inhibitors, especially from natural sources. In this study, we investigated 900 extracts fro...

Many skin-whitening compounds target tyrosinase because it catalyzes two rate-limiting steps in melanin synthesis. Although many tyrosinase inhibitors are currently available for a skin-whitening purpose, undesirable adverse effects are also reported. Thus, numerous efforts have been made to develop safer tyrosinase inhibitors from natural products. In line with this, we tested fifty flavonoids...

In this study, we repositioned thiopurine drugs used for the treatment of acute 12 leukaemia as new tyrosinase inhibitors. Tyrosinase catalyses two distinct and successive 13 oxidations in melanin biosynthesis: the conversions of tyrosine to dihydroxyphenylalanine (DOPA) 14 and DOPA to dopaquinone. Continuous efforts are underway to discover small molecule 15 inhibitors of tyrosinase for therap...

Objective: Tyrosinase as the key enzyme in melanin biosynthesis, involves in determining the color of mammalian skin and hair. A variety of dermatological disorders, come up from an unnecessary level of epidermal pigmentation. Plants are low-cost and rich sources of active compounds.  Methods: More than seventy native plants collected from the central region of Kurdistan province collected. Inh...