PT  - JOURNAL ARTICLE
AU  - Chaali, M.
AU  - Lecka, J.
AU  - Suresh, G.
AU  - Salem, M.
AU  - Brar, S. K.
AU  - Hernandez-Galan, L.
AU  - Sévigny, J.
AU  - Avalos Ramirez, A.
TI  - Supplement comprising of laccase and citric acid as an alternative for antibiotics – <em>in vitro</em> triggers of melanin production
AID  - 10.1101/179291
DP  - 2017 Jan 01
TA  - bioRxiv
PG  - 179291
4099  - http://biorxiv.org/content/early/2017/08/21/179291.short
4100  - http://biorxiv.org/content/early/2017/08/21/179291.full
AB  - An indiscriminate use of antibiotics in humans and animals has led to a widespread selection of antibiotic-resistant bacterial strains. A possible solution to counter this problem could be to develop alternatives that may boost the host immunity, thus reducing in the quantity and frequency of antibiotic use. In this work, for the first time, citric acid and laccase were used as extracellular inducers of melanin production in yeast cells and human cell lines. It is proposed that the formulation of laccase and citric acid together could further promote melatonin stimulated melanocyte derived melanin production. Melanization test as a probe of immunity, described in this study, is an easy and a quicker test than the other immunity tests and is statistically significant. The results showed the synergistic effect of citric acid and laccase on melanin production by the yeast cells, with significant statistical differences compared to all other tested conditions (P: 0.0005- 0.005). Laccase and citric acid together boosted melanin production after 8 days of incubation. An increase in melanin production by two colon human cells lines (Cacao-2/15 and HT-29) was observed when both laccase and citric acid were present in cell growth medium. A formulation with citric acid and laccase may prove to be an excellent alternative to reduce the antibiotic load in human and animal subjects.Summary statement This study shows, for the first time, that production of melanin in yeast and human intestinal cells is induced by extracellular addition of laccase and citric acid.