Effect of cytokinins on shoots proliferation and rosmarinic and salvianolic acid B production in shoot culture of Dracocephalum forrestii W. W. Smith

Abstract

The current study estimates the effect of different cytokinins on shoot proliferation and biosynthesis of caffeic acid derivatives in Dracocephalum forrestii in vitro culture. The shoots were grown on Murashige and Skoog (MS) agar medium with 1 µM indole-3-acetic acid (IAA) and different content of 6-benzyloaminopurine (BAP), zeatin, kinetin (1, 2, 4, 8, 18 µM) or thidiazuron (TDZ) (0.1, 0.2, 0.5, 1, 2 µM). The highest multiplication rate (about seven shoots and/or buds per explant) was obtained after 4 weeks of culture on MS medium with 1 µM IAA and 8 or 16 µM BAP. Optimal biomass of plant material was also received on the same media. The identity of the compounds present in the hydromethanolic extracts from D. forrestii shoots grown on cytokinin-supplemented media was confirmed using UPLC-PDA-ESI-MS method. The analysis revealed the presence of nine metabolites recognized as caffeic acid derivatives. The content of the predominant phenolic acids in the extracts, i.e. rosmarinic acid (RA) and salvianolic acid B (SAB), was determined with UHPLC. The highest yield of RA was found in shoots cultivated in the medium containing 1 µM IAA and 2 µM BAP (18.7 mg/g DW). The highest level of SAB (5.3-5.9 mg/g DW) was identified in multiple shoots grown in the presence of 1 µM IAA and 0.5-1 µM TDZ or 2 µM BAP.

Exogenous Kinetin Promotes the Nonenzymatic Antioxidant System and Photosynthetic Activity of Coffee (Coffea arabica L.) Plants Under Cold Stress Conditions

“…The kinetin-hydrogen peroxide-mediated reinforcement of the antioxidant system is supported by high amounts of antioxidant compounds analyzed in the current study (Figures 3-5). The current results are in agreement with several reports were exogenous kinetin treatment increased the tolerance of plants to abiotic stress conditions through the increased activities of antioxidant enzymes [34][35][36]52], as well as the increased contents of several antioxidant compounds, such as flavonoids, gibberellins, salicylic acid, jasmonic acid and abscisic acid in salinity-stressed soybean plants [37], proline in drought-stressed rice [39], salvianolic acid and rosmarinic acid in Dracocephalum forrestii [40]. Although the accumulation of several secondary metabolites in the leaves of coffee plants under oxidative stress conditions is a well-known phenomenon [15,16], this study is the first to report a profound increment in the contents of these compounds in response to exogenous kinetin treatment under optimal or cold stress conditions.…”

“…Although the mechanism of kinetin action in mitigating oxidative stresses is not yet clearly understood, it has been suggested that kinetin upregulates both the enzymatic and the nonenzymatic antioxidative systems, hence reinforcing the ROS scavenging abilities of plants [34]. The exogenous foliar application of kinetin activates and stimulates the biosynthesis of secondary metabolites through the upregulation of the corresponding transcripts or by increasing the activities of the biosynthetic enzymes in a number of plants [37,39,40]. Therefore, due to the repressed enzyme activity during cold stress conditions, amplification of the nonenzymatic antioxidative system through kinetin application might offer a necessary tolerance mechanism to enhance the growth of plants, such as coffee.…”

The Stimulatory Effect of Purine-Type Cytokinins on Proliferation and Polyphenolic Compound Accumulation in Shoot Culture of Salvia viridis

“…Following supplementation with 0.1 mg/L IAA and 0.45 mg/L BAP, Salvia officinalis shoots grown on MS medium produced 16.3 mg RA per g DW, which was similar to that found in the aerial parts of the plant cultivated in natural condition [31]. It has previously been found that BAP stimulated more effective biomass accumulation and RA and SAB production than zeatin, kinetin or TDZ in Dracocephalum forrestii shoot culture; however, higher BAP concentrations (8 and 16 µM) were the most optimal for growth, and lower ones (2 µM) were better for production [32]. In contrast, Santos-Gomes et al [33] report that kinetin yielded greater amounts of RA and CA in S. officinalis culture than BAP.…”

Transformed Shoots of Dracocephalum forrestii W.W. Smith from Different Bioreactor Systems as a Rich Source of Natural Phenolic Compounds

“…The D. forrestii shoots cultivated in the RITA and Plantform systems produced lower amounts of RA: 11.91 mg/g DW and 8.23 mg/g DW, respectively ( Table 2 ). However, these RA levels were several times higher than in the aerial parts of one-year-old intact plants (3.81 mg/g DW) [ 38 ]. The therapeutic potential of RA is well known [ 39 ].…”

“…To determine the phenolic compounds content, we subjected the obtained hydromethanolic extract to ultra-high performance liquid chromatography (UHPLC) analysis using an Agilent Technologies 1290 Infinity UHPLC apparatus equipped with a diode array detection (DAD) and Shield RP C18-column (2.19 × 100 mm, 1.7 μm pore size) at a temperature of 35 °C. Details of the analysis were presented earlier [ 38 ]. The compounds were identified by comparing the retention times of peaks (Rt), UV, and mass spectra of the samples with those of standards.…”