Abstract
Background:
Brassica is one of the herbs with potential in the field of medicine, containing active compounds such as glucosinolates. These compounds can be hydrolyzed into indole-3-carbinol (I3C) and 3,3′-diindolylmethane (DIM), which have been shown to have a positive impact on health. The stem part of cauliflower is often not utilized; therefore, it was used in this study.

Aim:
This study aimed to detect the presence of indole-3-carbinol (I3C) in cauliflower stem powder (BOVB) and evaluate its potential as an aromatase inhibitor in vivo.

Methods:
This study used cauliflower stems that were freeze-dried and milled into powder. The experimental animals used were Sprague Dawley rats with five treatments: P1 = distilled water (negative control); P2 = pure I3C 10.34 mg/day (positive control); P3 = 171.5 g/day; P4 = 343 g/day; P5 = 686 g/day. Treatment was conducted for 56 days with blood serum collection on day 7 (week 1), day 28 (week 4), day 42 (week 6), and day 56 (week 8). Blood serum was tested using enzyme-linked immunosorbent assay (ELISA) to measure serum testosterone and aromatase levels. Data were statistically analyzed using two-way analysis of variance and the Duncan test.

Results:
Rats administered BOVB suspension after 56 days showed a significant decrease in aromatase levels in the blood serum (P4 and P5) compared with those not administered (P1) in the 8th week. In contrast, serum testosterone levels tended to increase but showed no significant change in all groups and all weeks. In the 8th week, rats also showed a significant increase in body weight in the groups given BOVB suspension (P3, P4, and P5) compared to those not given the BOVB suspension (P1).

Conclusion:
BOVB supplementation significantly decreased serum aromatase levels, increased body weight, and showed a non-significant upward trend in testosterone levels. Further research is needed to elucidate the metabolic pathways, determine optimal safe dosages, and evaluate long-term clinical relevance.

Key words: Aromatase blocker; Cauliflower; Herbal therapy; Indole-3-carbinol; Testosterone.