Centre for Rural Development and Technology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, 110016, India,
Appl Biochem Biotechnol. 2014 Mar;172(6):2894-906. doi: 10.1007/s12010-014-0736-2. Epub 2014 Jan 23.
Steviol glycosides are natural non-caloric sweeteners which are extracted from the leaves of Stevia rebaudiana plant. Present study deals the effect of salts (NaCl and Na2CO3) on callus and suspension culture of Stevia plant for steviol glycoside (SGs) production. Yellow-green and compact calli obtained from in vitro raised Stevia leaves sub-cultured on MS medium supplemented with 2.0 mg l(-1) NAA and different concentrations of NaCl (0.05-0.20%) and Na2CO3 (0.0125-0.10%) for 2 weeks, and incubated at 24 ± 1 °C and 22.4 μmol m(-2) s(-1) light intensity provided by white fluorescent tubes for 16 h. Callus and suspension biomass cultured on salts showed less growth as well as browning of medium when compared with control. Quantification of SGs content in callus culture (collected on 15th day) and suspension cultures (collected at 10th and 15th days) treated with and without salts were analyzed by HPLC. It was found that abiotic stress induced by the salts increased the concentration of SGs significantly. In callus, the quantity of SGs got increased from 0.27 (control) to 1.43 and 1.57% with 0.10% NaCl, and 0.025% Na2CO3, respectively. However, in case of suspension culture, the same concentrations of NaCl and Na2CO3 enhanced the SGs content from 1.36 (control) to 2.61 and 5.14%, respectively, on the 10th day.
甜菊糖苷是从甜叶菊植物叶子中提取的天然无热量甜味剂。本研究探讨了盐（NaCl 和 Na2CO3）对甜叶菊愈伤组织和悬浮培养物生产甜菊糖苷（SGs）的影响。从离体培养的甜叶菊叶片中获得的黄绿色、致密的愈伤组织，在 MS 培养基上继代培养，培养基中添加 2.0 mg l(-1) NAA 和不同浓度的 NaCl（0.05-0.20%）和 Na2CO3（0.0125-0.10%），培养 2 周，在 24 ± 1°C 和 22.4 μmol m(-2) s(-1)由白色荧光管提供的光强度下培养 16 小时。与对照相比，在盐处理的愈伤组织和悬浮生物量培养物中，生长和培养基褐变较少。通过 HPLC 分析未处理和处理过的盐的愈伤组织培养物（第 15 天收集）和悬浮培养物（第 10 天和第 15 天收集）中 SGs 含量。结果表明，盐诱导的非生物胁迫显著增加了 SGs 的浓度。在愈伤组织中，SGs 的量从 0.27（对照）分别增加到 1.43 和 1.57%，用 0.10% NaCl 和 0.025% Na2CO3 处理。然而，在悬浮培养物中，相同浓度的 NaCl 和 Na2CO3 分别将 SGs 含量从 1.36（对照）提高到 2.61 和 5.14%，在第 10 天。
