Indian sarsaparilla, Hemidesmus indicus (L.) R. Br. ex Schult: tissue culture studies

Elicitor mediated enhancement of shoot biomass and lupeol production in Hemidesmus indicus (L.) R. Br. ex. Schult. and Tylophora indica (Burm. F.) Merrill using yeast extract and salicylic acid

Hemidesmus indicus (L.) R. Br. ex Schult. and Tylophora indica (Burm. F.) Merrill shoot cultures were treated with different concentrations of yeast extract (YE; 25-200 mg/L) and salicylic acid (SA; 50-200 µM), and their effect on lupeol production was assessed. The maximum dry weight (DW) biomass was recorded when H. indicus shoots were treated with SA (50 µM) and T. indica shoots with YE (200 mg/L). Highest lupeol yield (335.40 ± 0.04 µg/g DW) was obtained in H. indicus shoots after treatment with 50 µM of SA for 3 weeks. Whereas in T. indica, maximum lupeol content (584.26 ± 8.14 µg/g DW) was recorded by giving treatment with 25 μM of SA for 6 weeks.

An in vitro Propagation of Aspilia africana (Pers.) C. D. Adams, and Evaluation of Its Anatomy and Physiology of Acclimatized Plants

Aspilia africana (Pers.) C. D. Adams is an important medicinal plant, that has been used as traditional medicine in many African countries for the treatment of various health problems, including inflammatory conditions, osteoporosis, tuberculosis, cough, measles, diabetes, diarrhea, malaria, and wounds. We developed an efficient and reproducible protocol for in vitro regeneration of A. africana from nodes. We assessed the effects of plant tissue culture media on A. africana growth, cytokinins for in vitro shoot regeneration and proliferation, and auxins for the rooting of regenerated shoots. Furthermore, chlorophyll content, photosynthetic rates, anatomy (leaves, stems, and roots), and Fourier transform near-infrared (FT-NIR) spectra (leaves, stems, and roots) of the in vitro regenerated and maternal A. africana plants were compared. Murashige and Skoog media, containing vitamins fortified with benzylaminopurine (BA, 1.0 mg/l), regenerated the highest number of shoots (13.0 ± 0.424) from A. africana nodal segments. 1-naphthaleneacetic acid (NAA, 0.1 mg/l) produced up to 13.10 ± 0.873 roots, 136.35 ± 4.316 mm length, and was the most efficient for rooting. During acclimatization, the in vitro regenerated A. africana plants had a survival rate of 95.7%, displaying normal morphology and growth features. In vitro regenerated and mother A. africana plants had similar chlorophyll contents, photosynthetic rates, stem and root anatomies, and FT-NIR spectra of the leaf, stem, and roots. The established regeneration protocol could be used for large-scale multiplication of the plant within a short time, thus substantially contributing to its rapid propagation and germplasm preservation, in addition to providing a basis for the domestication of this useful, high-value medicinal plant.

Boosting leaf contents of rutin and solanesol in bio-waste of Solanum lycopersicum

In tomato production, the accruing green biomass shows promising potential as source of health-promoting compounds, such as rutin and solanesol, that are of high interest due to their medicinal properties. Naturally, they accumulate in plants growing in suboptimal growing conditions, e.g. influenced by biotic and abiotic stressors. With the aim to evaluate the potential use of tomato residues as source, we analyzed both leaf metabolites during a complete cultivation cycle, while applying single and combined stresses practically realized in greenhouse production. In the late season, contents of both metabolites were significantly enhanced by nutrient deficit in combination with 2 °C colder nights for 4 weeks and prolonged for in total 9 weeks. Particularly, higher solanesol contents were achieved by salt stress and elevated temperature after one week, even stronger when combined with drought. At harvest, stressed plants consist of less green biomass reducing the overall economic potential. However, practicable abiotic stresses should be considered as potential tool to induce the accumulation of beneficial compounds. Extracting profitable metabolites from the green biomass of the model crop tomato supports the overall goal to promote sustainable approaches in horticultural production.