**2.1. Cytotoxicity**

bamboo), *Phyllostachys heterocycla* Milf (Moso bamboo), and *Dendrocalamus latiflorus* Munro (Ma bamboo) [2]. This indicates that bamboo is one of the economic green resources in Taiwan. Among these bamboos, Moso bamboo has been mainly used as a material for the making of furniture, handicrafts, and athletic/leisure goods, because it can grow over 20 m tall and 60–150 mm in diameter in one growing season [3]. Moreover, bamboo is accumulated from

but it can naturally decay by organic compound oxidization or be burned, and this produces

Bamboo and its products show good prospects for commercial applications, when considering the need for the protection of our wood resources and environmental balance. It is therefore important to study the characteristics of bamboo and its by-products in order to make good use of them. Domestic and foreign manufacturers and researchers have invested a great deal of money, labor and time to discover the characteristics and functions of charcoal in recent years. Bamboo charcoals are mainly derived from 4-year-old or older bamboo as raw materials [4–7]. The utilization of bamboo charcoal, conventionally regarded as fuel, is widely applied to daily life or/and industry. The use of bamboo charcoal is more wide and diverse because it is a porous material with a high specific surface area that has lots of functions, such as indoor deodorization, humidity control, water quality improvement, air purification and so on [5, 8, 9]. Recently, there has been a tendency to maintain good health from food products. Some food producers have added charcoal materials into food products, for example, charcoal bread/ cookies, charcoal peanuts, charcoal ice cream, etc. This is advertised as being able to absorb unclean substances, such as heavy metal elements, and producers have exaggerated that these materials can clean the intestines and stomach after eating. However, in May of 2006, the Department of Health's Executive Yuan, Taiwan, announces that the charcoals can only be used as colorants of food without any medical and health effects, that is, as a natural black pigment only [10]. The charcoals can be added as a pigment in food, but it is a profound question whether or not residue *in vivo* causes any harm by inducing cell lesions or carcinogens. The application of bamboo vinegar (brown-red transparent liquids), even the compounds that are complex and different, is mainly able to be divided into three main portions: acid, phenol, and neutral compounds [11]. The vinegar consists of 80–200 compounds: 32% organic acid, 40% phenolic compound, 3% aldehyde, 5% alkone compound, 5% alcohol compound, 4% ester compound, and 5% others. When bamboo vinegar is dehydrated, there is usually 80% water [12–15]. The organic compounds in bamboo vinegars may have practical applications even when present in only trace quantities [14, 16], such as in improving soil, promoting crops and preventing worm growth, as well as reducing agricultural chemicals, compost odor and sterilization [12]. Recently, bamboo vinegars have been developed that are beneficial for promoting growth of plants to as a plant root growth promoter or a pH value adjuster of cultural media [17–19]. It is also effective when used against allergies [20], in healthy drinks [13, 21, 22], as a virus/fungi/bacterial resistant [16, 23–27] and as an agent of antioxidation, especially for a resistant lipid oxidation effect [15]. As stated in the above references, the commercial production of bamboo vinegar is being increased and highly valued for its diverse effective uses

 that returns to the atmosphere. To decrease bamboo decaying or burning, the preparation of charcoal becomes one of the selected methods because carbon can extend the lifetime of bamboo [4]. In other words, the charcoals can also become earth friendly materials because

concentration in the atmosphere.

) by photosynthesis,

organic compounds from which a bamboo converts carbon dioxide (CO<sup>2</sup>

they can slow down the increase of CO<sup>2</sup>

50 Bamboo - Current and Future Prospects

CO<sup>2</sup>

The methods of the cytotoxicity for the bamboo charcoal and vinegars are taken 1.0, 2.5, 5.0, 7.5, and 10.0 mg of bamboo charcoal, as well as 0.1 mL of bamboo vinegars, collected at different temperatures (80–150, over 80, 90–92, 99–102, 120–123, and 145–150°C), from the exit of chimney of earthen kiln are diluted to a percent content of 50, 33.33, 25, 20, 13.33, and 10%, respectively. Both of them are examined with *S. typhimurium* TA98 and TA100 for either S9 (+S9) or zero S9 (-S9) in accordance with the Ames test and the experimental procedure referred to [32, 37–39]. The colony count is calculated; if the bacterial count of the test group (+S9 or -S9) is larger than the bacterial count of the control group (no bamboo charcoal/vinegars) by 80% (the bacterial count rate, Survival), there is no toxicity [35]. The Survival (%) is the residual bacteria rate that is the percentage relative to the control (100%). The formula of the Survival of cytotoxicity is: Survival (%) = (the bacterial count of test group/the bacterial count of control group) × 100.

very low. Both Cd and Hg in the charcoal are closed to 0.5 ppm. The Pb in the charcoal is 2.9 ppm. That meets the Sanitation Standard for Edible Natural Colorants, Food Sanitation

Preliminary Safety Evaluation of Bamboo Pyrolysis Products: Charcoal and Vinegar

http://dx.doi.org/10.5772/intechopen.68542

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The cytotoxicity test results with 1.0, 2.5, 5.0, 7.5 and 10.0 mg of Moso bamboo charcoal for *S. typhimurium* TA98 and TA100 are shown in **Figure 1**. The Survival (%) of the Moso bamboo charcoal with either zero S9 (-S9) or S9 (+S9) is higher than 80%. Waleh *et al*. [36] indicate that the amount of residual bacteria of S. *typhimurium* must be over 80% of the control group (Control) to determine that the test group has no cytotoxicity for S. *typhimurium* [36]. The Survival of the charcoals is higher than that of control by more than 80%, indicating that the Moso bamboo charcoal has no cytotoxicity for the test strains in the additional range of 1–10 mg/plate, and the dose for the mutagenicity test can be selected according to this range.

**Figure 2** shows the mutagenicity test results of the Moso bamboo charcoal for *S. typhimurium* TA98 and TA100. The bamboo charcoal, without or with S9, in the test range (1–10 mg/plate) does not exceed spontaneous revertants by more than two times for TA98 and TA100, that is, the mutagenicity ratio (MR) is smaller than 2. According to the standards proposed by Ames *et al*. [32], if the number of spontaneous revertants induced by the specimen is larger than the spontaneous revertants of the control group by more than two times, the specimen has

**Figure 1.** Cytotoxicity of Moso bamboo charcoal toward *S. tyhpimurium* TA98 and TA100 without or with S9 mix.

Standards (1989), Ministry of Health and Welfare in Taiwan at below 40 ppm [41].

**3.2. Cytotoxicity of bamboo charcoal**

**3.3. Mutagenicity of bamboo charcoal**
