Protoplasts of three carrot cultivars were isolated from in vitro-grown plantlets by overnight incubation in an enzyme mixture composed of 1% (w/v) cellulase Onozuka R-10 and 0.1% (w/v) pectolyase Y-23. After cell immobilization in modified thin alginate layers, three types of β-lactam antibiotics (cefotaxime, carbenicillin, or timentin) at five different concentrations (100, 200, 300, 400, or 500 mg L-1) were added to the culture medium. In 20-d-old cultures, a different number of cell colonies had formed and varied on average from 27 to 56% in carbenicillin- and cefotaxime-containing media, respectively. Supplementation of the culture media with antibiotics at concentrations higher than 100 mg L-1 resulted in a decrease in plating efficiency in comparison with the controls. However, from all antibiotic treatments, except carbenicillin at concentrations of 400-500 mg L-1, efficient plant regeneration occurred. For this reason, we believe that cefotaxime and timentin in the concentrations analyzed here may be used in complex in vitro procedures or valuable carrot cultures as a prophylactic agent for prevention against occasional contaminations.

中文翻译：

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β-内酰胺类抗生素对胡萝卜原生质体培养物中植物再生的影响。

通过在由 1% (w/v) 纤维素酶 Onozuka R-10 和 0.1% (w/v) 果胶裂解酶 Y-23 组成的酶混合物中过夜孵育，从体外培养的小植株中分离出三种胡萝卜品种的原生质体。在修饰的海藻酸盐薄层中固定细胞后，将三种类型的 β-内酰胺抗生素（头孢噻肟、羧苄青霉素或特美汀）以五种不同浓度（100、200、300、400 或 500 mg L-1）添加到培养基中. 在 20 天龄的培养物中，在含羧苄青霉素和头孢噻肟的培养基中，形成了不同数量的细胞集落，平均变化范围分别为 27% 至 56%。与对照相比，在培养基中添加浓度高于 100 mg L-1 的抗生素会导致电镀效率降低。然而，从所有抗生素治疗中，除了浓度为 400-500 mg L-1 的羧苄青霉素外，植物再生都有效。出于这个原因，我们相信这里分析的浓度的头孢噻肟和特美汀可用于复杂的体外程序或有价值的胡萝卜培养物，作为预防偶然污染的预防剂。