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Chinese cabbage (Brassica rapa ssp. pekinensis), a green vegetable with high nutritional value, has been found to be rich in glucosinolates. Brassinosteroids (BRs), which regulate various plant growth and development processes, have been studied for their effect on glucosinolate production in in vitro shoot cultures. In this study, the most active compound in brassinosteroids, brassinolide, was used at different concentrations to test its effect on glucosinolate biosynthesis. A total glucosinolate content of 8.512 µmol g−1 DW was observed on MS optimal medium supplemented with 0.2 mg L−1 brassinolide. The expression of key genes related to glucosinolate biosynthesis and brassinolide signaling pathways was upregulated by brassinolide treatment. This research provides valuable insights for pharmaceutical and food companies interested in producing consistent levels of glucosinolates in Chinese cabbage shoots through the use of brassinolide.Key message: Inclusion of brassinolide in the culture medium triggered glucosinolates biosynthesis in shoot culture of Chinese cabbage. [ABSTRACT FROM AUTHOR]

In vitro culture and genetic transformation of black gram are difficult due to its recalcitrant nature. Establishment of gene transfer procedure is a prerequisite to develop transgenic plants of black gram in a shorter period. Therefore, genetic transformation was performed to optimize the factors influencing transformation efficiency through Agrobacterium tumefaciens-mediated in planta transformation using EHA 105 strain harbouring reporter gene, bar, and selectable marker, gfp- gus, in sprouted half-seed explants of black gram. Several parameters, such as co-cultivation, acetosyringone concentration, exposure time to sonication, and vacuum infiltration influencing in planta transformation, have been evaluated in this study. The half-seed explants when sonicated for 3 min and vacuum infiltered for 2 min at 100 mm of Hg in the presence of A. tumefaciens (pCAMBIA1304 - bar) suspensions and incubated for 3 days co-cultivation in MS medium with 100 µM acetosyringone showed maximum transformation efficiency (46 %). The putative transformants were selected by inoculating co-cultivated seeds in BASTA (4 mg l) containing MS medium followed by BASTA foliar spray on 15-day-old black gram plants (35 mg l) in green house, and the transgene integration was confirmed by biochemical assay (GUS), Polymerase chain reaction, Dot-blot, and Southern hybridisation analyses. [ABSTRACT FROM AUTHOR]

Agrobacterium tumefaciens-mediated transformation system was established for Hybanthus enneaspermus using leaf explants with the strain LBA4404 harbouring pCAMBIA 2301 carrying the nptII and gusA genes. Sensitivity of leaf explants to kanamycin was standardized (100 mg/l) for screening the transgenic plants. Transformation parameters (OD, virulence inducer, infection time, co-cultivation period, bactericidal antibiotics, etc.) influencing the gene transfer and integration were assessed in the present investigation. Fourteen-day pre-cultured explants were subjected with Agrobacterium strain LBA4404. Optimized parameters such as culture density of 0.5 OD, infection time of 6 min, AS concentration of 150 µM with 3 days co-cultivation revealed maximum transformation efficiency based on GUS expression assay. The presence of gusA in transgenics was confirmed by polymerase chain reaction and Southern blotting analysis. The present transformation experiment yielded 20 shoots/explant with higher transformation efficiency (28 %). The protocol could be used to introduce genes for trait improvement as well as for altering metabolic pathway for secondary metabolites production. [ABSTRACT FROM AUTHOR]

Hybanthus enneaspermus is an ethanobotanical plant extensively used in Indian traditional medicine. Quick and efficient in vitro mass propagation of this plant species was established for commercial utilization from leaf and node explants using various concentrations and combinations of plant growth regulators and polyamines. The maximum number of multiple shoots per leaf explant (40 shoots) was achieved on MS medium supplemented with 20 mg/l spermidine in combination with 4 mg/l BA+1.5 mg/l IAA after 8 weeks of culture. The elongated shoots were rooted (16 roots/shoot) on MS medium with the best concentration of IBA (1.5 mg/l) and in combination with 20 mg/l putrescine after 5 weeks of culture. The plants were successfully acclimatized (98 %) in the sand: soil: vermiculite mixture (1:1:1 v/ v/ v) in the greenhouse. An increased antioxidant activity was recorded in vitro regenerated shoots when compared to in vitro-induced roots. L-Dopa content was recorded higher in leaves (8.31 mg/g DW) followed by stem (6.22 mg/g DW) and root (3.22 mg/g DW) of leaf-derived plants than the field-grown parent plant after 5 weeks. By adopting this protocol, the regenerated-plants could be used for drug production and pharmacology work with as an alternative to field-grown plants. [ABSTRACT FROM AUTHOR]

Effect of nitrogen and carbon sources on multiple shoot regeneration and withanolides contents of Withania somnifera were evaluated. Inclusion of l-glutamine (20 mg/l) in medium fortified with the optimal levels of 1.5 mg/l 6-benzyladenine (BA) and 0.3 mg/l indole-3-acetic acid (IAA) resulted in the production of 58 shoots/explant. Sucrose at 4 % and 20 mg/l l-glutamine with idéal concentrations of BA and IAA improved shoot multiplication (62 shoots/explant) while 6 % sucrose enhanced withanolides contents in regenerated multiple shoots. All the shoots were rooted (26 roots/shoot) when cultured in MS medium amended with 15 mg/l ammonium nitrate, 2 mg/l IBA, and 2 % sucrose. The present study resulted in the production of 4.42-fold higher multiple shoots and 2.6-fold higher roots as well as enhancing the contents of all major withanolides (withaferin A, withanone, withanolide A and B) in regenerated plants when compared to previous reports on W. somnifera regeneration. [ABSTRACT FROM AUTHOR]

The influence of Gracilaria edulis and Sargassum wightii extracts was investigated for the production of biomass and withanolides in the multiple shoot suspension culture of Withania somnifera. Supplementation of 40 % G. edulis extract in MS liquid medium for 24 h exposure time in the culture recorded the highest biomass accumulation [62.4 g fresh weight and 17.82 g dry weight (DW)] and withanolides production (withanolide A 0.76 mg/g DW; withanolide B 1.66 mg/g DW; withaferin A 2.80 mg/g DW and withanone 2.42 mg/g DW) after 5 weeks of culture, which were 1.45-1.58-fold higher than control culture. This naturally available G. edulis extract-treated multiple shoot suspension culture protocol offers a potential alternative for the optimum production of biomass and withanolides utilizing shake-flasks. [ABSTRACT FROM AUTHOR]

A combined treatment of sonication (2 min) and vacuum infiltration (2 min) stimulated isoflavones production of 75.26 mg g DW which was 15.11-fold higher than control hairy root line at optimal harvest time of 40 days. Addition of MeJ at 100 μM concentration with 72 h exposure time on 30 day-old hairy root culture further enhanced total isoflavones production of 53.16 mg g DW (10.67-fold) and SA at 200 μM concentration with 96 h exposure period enhanced the production of isoflavones (28.79 mg g DW; 5.78-fold). MeJ-treated hairy roots reduced biomass accumulation whereas sonication, vacuum infiltration and SA did not exhibit a negative effect on biomass growth. [ABSTRACT FROM AUTHOR]

To determine the possibility of generating the Podophyllotoxin accumulation using Podophyllum hexandrum adventitious roots derived from root segments, several nutrient constituents (carbon sources, media strength, initial medium pH, ammonium and nitrate proportion and phosphate ratio) were evaluated in culture. The maximum biomass accumulation was recorded in 0.50 MS medium containing 3 mg/l indole-3-butyric acid and 2 % sucrose, and the maximum accumulation of Podophyllotoxin was documented in the same strength of MS medium with 6 % of sucrose. When the initial medium pH was on 6 in the optimized MS medium, the biomass and Podophyllotoxin accumulations were highest. The lower concentration of ammonium (10 mM) in combination with a moderate concentration of nitrate (20 mM) was found ideal for maximum accumulations of biomass and Podophyllotoxin. Maximum Podophyllotoxin accumulation (6.4 mg/g dry weight) was recorded at the higher concentration of phosphate (2.25 mM), and lower concentration of phosphate (1.25 mM) showed highest growth accumulation. The outcome of the present work will be helpful for the large-scale cultivation of adventitious root for the production of Podophyllotoxin. [ABSTRACT FROM AUTHOR]

Key message: An efficient, reproducible and genotype-independent in planta transformation has been standardized for sugarcane using seed as explant. Abstract: Transgenic sugarcane production through Agrobacterium infection followed by in vitro regeneration is a time-consuming process and highly genotype dependent. To obtain more number of transformed sugarcane plants in a relatively short duration, sugarcane seeds were infected with Agrobacterium tumefaciens EHA 105 harboring pCAMBIA 1304- bar and transformed plants were successfully established without undergoing in vitro regeneration. Various factors affecting sugarcane seed transformation were optimized, including pre-culture duration, acetosyringone concentration, surfactants, co-cultivation, sonication and vacuum infiltration duration. The transformed sugarcane plants were selected against BASTA and screened by GUS and GFP visual assay, PCR and Southern hybridization. Among the different combinations and concentrations tested, when 12-h pre-cultured seeds were sonicated for 10 min and 3 min vacuum infiltered in 100 µM acetosyringone and 0.1 % Silwett L-77 containing Agrobacterium suspension and co-cultivated for 72-h showed highest transformation efficiency. The amenability of the standardized protocol was tested on five genotypes. It was found that all the tested genotypes responded favorably, though CoC671 proved to be the best responding cultivar with 45.4 % transformation efficiency. The developed protocol is cost-effective, efficient and genotype independent without involvement of any tissue culture procedure and can generate a relatively large number of transgenic plants in approximately 2 months. [ABSTRACT FROM AUTHOR]

Withanolide is one of the most extensively exploited steroidal lactones, which are biosynthesized in Withania somnifera. Its production from cell suspension culture was analyzed to defeat limitations coupled with its regular supply from the plant organs. In order to optimize the different factors for sustainable production of withanolides and biomass accumulations, different concentrations of auxins or cytokinins and their combinations, carbon sources, agitation speed, organic additives and seaweed extracts was studied in cell suspension culture. Maximum biomass accumulation (16.72 g fresh weight [FW] and 4.18 g dry weight [DW]) and withanolides production (withanolide A 7.21 mg/g DW, withanolide B 4.23 mg/g DW, withaferin A 3.88 mg/g DW and withanone 6.72 mg/g DW) were achieved in the treatment of Gracilaria edulis extract at 40 % level. Organic additive l-glutamine at 200 mg/l in combination with picloram (1 mg/l) and KN (0.5 mg/l) promoted growth characteristics (11.87 g FW and 2.96 g DW) and withanolides synthesis (withanolide A 5.04 mg/g DW, withanolide B 2.59 mg/g DW, withaferin A 2.36 mg/g DW and withanone 4.32 mg/g DW). Sucrose at 5 % level revolved out to be a superior carbon source yielded highest withanolides production (withanolide A 2.88 mg/g DW, withanolide B 1.48 mg/g DW, withaferin A 1.35 mg/g DW and withanone 2.47 mg/g DW), whereas biomass (7.28 g FW and 1.82 g DW) was gratefully increased at 2 % level of sucrose in cell suspension culture. This optimized protocol can be utilized for large scale cultivation of W. somnifera cells in industrial bioreactors for mass synthesis of major withanolides. [ABSTRACT FROM AUTHOR]

Withania somnifera, an important medicinal plant that possesses a variety of bioactive secondary metabolites collectively known as withanolides. Hairy roots with an initial inoculum mass of 5 g FW were elicited separately with methyl jasmonate (MeJ) and salicylic acid (SA) at various concentrations for different exposure times after 30 days of culture. Enhanced production of biomass (32.68 g FW and 5.54 g DW; 1.23-fold higher), withanolide A (132.44 mg/g DW; 58-fold higher), withanone (84.35 mg/g DW; 46-fold higher), and withaferin A (70.72 mg/g DW; 42-fold higher) were achieved from 40 day-old harvested hairy roots elicited with 150 μM SA for 4 h exposure time. The present study reports a higher production of withanolide A, withanone and withaferin A from the elicited-hairy roots of W. somnifera under optimal inoculum mass, harvest time, elicitor exposure time and its concentration. These results will be useful for biochemical and bioprocess engineering for the viable production of withanolides in hairy root culture. [ABSTRACT FROM AUTHOR]

The influence of cytokinins and culture conditions including medium volume, harvest time and elicitation with abiotic elicitors (SA/MeJ) have been studied for the optimal production of biomass and withanolides in the multiple shoot culture of Withania somnifera. Elicitation of shoot inoculum mass (2 g l FW) with SA at 100 μM in the presence of 0.6 mg l BA and 20 mg l spermidine for 4 h exposure time at the 4th week in 20 ml liquid medium recorded higher withanolides production (withanolides A [8.48 mg g DW], withanolides B [15.47 mg g DW], withaferin A [29.55 mg g DW] and withanone [23.44 mg g DW]), which were 1.14 to 1.18-fold higher than elicitation with MeJ at 100 μM after 5 weeks of culture. SA-elicited cultures did not exhibit much variation in biomass accumulation when compared to control. This cytokinin induces and SA-elicited multiple shoot culture protocol provides a potential alternative for the optimal production of biomass and withanolides utilizing liquid culture. [ABSTRACT FROM AUTHOR]

Adventitious root cultures derived from leaf derived callus of Withania somnifera (L.) Dunal were treated with methyl jasmonate and salicylic acid independently. Biomass accumulation, culture age, elicitation period, and culture duration were optimized for higher withanolides production in the two best-responding varieties collected from Kolli hills (Eastern Ghats) and Cumbum (Western Ghats) of Tamil Nadu, India. Between the two elicitors, salicylic acid (SA) improved the production of major withanolides (withanolide A, withanolide B, withaferin A, and withanone) as well as minor constituents (12-deoxy withastramonolide, withanoside V, and withanoside IV) in the Kolli hills variety. Treatment of root biomass (11.70 g FW) on 30-day-old adventitious root cultures with 150 μM SA for 4 h elicitor exposure period resulted in the production of 64.65 mg g dry weight (DW) withanolide A (48-fold), 33.74 mg g DW withanolide B (29-fold), 17.47 mg g DW withaferin A (20-fold), 42.88 mg g DW withanone (37-fold), 5.34 mg g DW 12-deoxy withastramonolide (nine fold), 7.23 mg g DW withanoside V (seven fold), and 9.45 mg g DW withanoside IV (nine fold) after 10 days of elicitation (40th day of culture) when compared to untreated cultures. This is the first report on the use of elicitation strategy on the significant improvement in withanolides production in the adventitious root cultures of W. somnifera. [ABSTRACT FROM AUTHOR]

An efficient mass multiplication protocol was developed for Withania somnifera (L.) Dunal from nodal explants of field-grown plants on Murashige and Skoog medium (MS) supplemented with 6-benzyladenine (BA) [1.5 mg L], indole-3-acetic acid (IAA) [0.3 mg L] and with the addition of polyamine, spermidine (20 mg L) (shoot multiplication medium). A total of 46.4 shoots were obtained from nodal explants and they were elongated in the same medium in a culture duration of 6 weeks. The elongated shoots produced roots in MS medium fortified with putrescine (20 mg L) after 4 weeks, and all the rooted plants were successfully hardened and acclimatized with a survival rate of 100%. An average of 276 shoots (46 × 6) was produced when at least six nodal explants obtained from each of the 46 in vitro grown shoots were cultured by microcutting method in the same shoot multiplication medium. On an average, 12,696 plants could be produced from all the shoots (276 × 46) by microcuttings in a period of 7 months. HPLC revealed a significant increase in the quantities of withanolide A, withanolide B, withaferin A and withanone in the leaves, stems, and roots of in vitro regenerated plants compared to the field-grown parent plants. Ploidy analysis using flow cytometry revealed genetic stability of in vitro regenerated plants. This protocol will be useful for scale-up production of withanolides on commercial scale. [ABSTRACT FROM AUTHOR]