# Use of Fermented Black Tea (Camellia sinensis) Factory Wastes in Standard Rat Diets

## TL;DR

This study shows that fermented black tea factory waste can be safely added to rat diets without harming their health and may even improve antioxidant levels.

## Contribution

The first study to investigate the use of fermented black tea factory waste in rodent diets.

## Key findings

- No significant differences in body weight, organ weights, or blood parameters were observed across groups.
- The 10% tea waste group showed the highest antioxidant levels and lowest oxidative stress.
- No health issues or pathological findings were observed in any group.

## Abstract

This study investigates fermented black tea factory production waste (FTFW) in rat diets, which has not been explored before. The goal is to assess the effects of FTFW, a waste considered environmentally harmful, on nutrition, health, and biochemical parameters in rats. Forty male rats were divided into four groups and fed diets with different amounts of tea waste (0%, 3%, 5%, and 10%) for 63 days. After the experiment, blood and organ samples were analyzed. The results showed that the caffeine in the tea waste was mostly removed during pellet production, and there were no significant differences in body weight, organ weights, or blood parameters between the groups. Additionally, no health issues or behavioral changes were observed. The group fed the highest amount of tea waste (10%) showed the best antioxidant levels, with lower oxidant levels and oxidative stress. Unlike other studies on tea extracts, no negative effects were found with FTFW. The study suggests that FTFW can be safely added to rat diets without harming their health, offering a low-cost, environmentally friendly way to turn waste into a beneficial product.

Although there are studies on the use of different tea extracts in animal diets, there are no studies on the use of fermented black tea factory production waste (FTFW) in rodent diets. This study aims to evaluate the effects of FTFW, considered an environmentally hazardous waste, in standard rat diets regarding nutritional, histopathological, and biochemical parameters. In this study, 40 male Wistar albino rats (70 days old, with a live weight of 200–250 g) were divided into four groups, each containing 10 rats. They were fed standard rat diets for 63 days, with varying amounts (0%, 3%, 5%, and 10%) of tea production waste. At the end of the experiment, biochemical analysis of blood and histopathological analysis of all organs were performed. There was no significant difference between the groups in terms of body weight, internal organ weights, or serum biochemical parameters (p > 0.05). No pathological findings were observed in any of the groups. The group receiving 10% tea waste, which had the highest total polyphenol level (1.42 ppm), also showed the highest serum total antioxidant status (TAS) (p < 0.05). In contrast, this group had the lowest total oxidant status (TOS) and oxidative stress index (OSI) levels (p < 0.05). The study concluded that FTFW can be included in the pellet diet of rats without changing their general health status and that a potential environmental pollutant can be used in rat diets.