No abstract

Red beet plants are rich in betalains that can be used as food natural colorants. Betalains were extracted from red beet and encapsulated with different carrier agents and freeze or spray dried. Effect of different encapsulating agents as maltodextrin, guar gum, gum Arabic, pectin and xanthan gum with different concentration (as encapsulating agents) were studied on the betalain stability. Encapsulated betalains with xanthan gum with maltodextrin showed about 65 % more recovery than the control. Encapsulation showed a higher recovery of betalains during freeze drying by 1.3 times than during spray drying. Spray dried samples has L* (lightness) higher than the freeze dried samples. The variations of maltodextrin with xanthan and guar gum freeze dried have highest chroma value of 21. The stabilization of pure betalain pigments may boost the use of these colouring molecules in the food industry and promote their application.

No abstract

In the present study, the effects of the metabolite elicitors chitosan, methyl jasmonate (MeJA) and salicylic acid (SA) as well as the hairy root transformation were tested for silymarin and phenolic compound accumulation in in vitro cultures of Milk thistle. For callus induction, leaf explants were cultured on MS medium supplemented with 5 mg/l NAA + 2 mg/l Kin + 0.1 mg/l GA3. Chitosan, SA and MeJA were added separately in three concentrations 200, 400 and 800 mg/l; 10, 20 and 40 mg/l; 20, 40 and 80 mg/l, respectively, to hormone free B5 medium. Alternatively, cotyledons of 12 day old seedlings were transformed with Agrobacterium rhizogenes A4 strain. Overall, increasing the concentrations of the three elicitors dramatically increased the total silymarin content. Remarkably, the elicitors mainly enhanced the accumulation of silybine A&B that were not detected in un-treated callus culture (control). In addition, the hairy root culture triggered the accumulation of silybine A&B, and silydianin, which was not detected in the non-transgenic roots. The hairy root culture was superior in production of the phenolic compounds in comparison to the control and elicitor treatments. The hairy root cultures showed also higher antioxidant capacities than non-transformed cultures and/or chemically elicited-callus cultures. Thus hairy root provide instrumental in enhancing the production of economically valuable metabolite.

No abstract

Transformed hairy root culture in common buckwheat (Fagopyrum esculentum Moench Rubra cultivar) was investigated for accumulation of amino acids and specific flavonoids. Leaves and stems of F. esculentum were used a starting material for induction of hairy roots via the Agrobacterium rhizogenes A4 strain. The transformed lines were confirmed by PCR detection of rol B gene, and their capability to continuously form hairy roots. Three lines from each explant types depending upon growth kinetics were observed. The hairy root lines were used to measure the contents of 17 amino acids and 3 flavonoids. Overall, the hairy root lines exhibited elevated accumulation of semiessential amino acids such as lysine, isoleucine, valine, histidine and phenylalanine. Content of proline was increased 3-5 times, likely due to the biotic stress reaction induced with A. rhizogenes. Determination of flavonoids by high-performance liquid chromatography, hesperidine and kaempferol-3-rutinoside, were accumulated in hairy root cultures and didn't detected in non-transformed root. The increase in flavonoids positively correlated with the antioxidant capacity of the hairy root cultures.

Hairy root culture is a promising alternative method for the production of secondary metabolites. In this study, transformed root of Linum usitatissimum was established using Agrobacterium rhizogenes A4 strain from root cultures for lignans, phenolic acids and antioxidant capacity determination. Total lignin content (secoisolariciresinol diglucoside, secoisolariciresinol and matairesinol) was 55.5% higher in transformed root cultures than in the non-transformed root culture. Secoisolariciresinol was detected in higher concentration (2.107 μmol/g DM) in the transformed root culture than non-transformed culture (1.099 μmol/g DM). Secoisolariciresinol diglucoside and matairesinol were exclusively detected in the transformed root culture, but were not found in the non-transformed root culture. The overall production of phenolic acids in transformed roots was approximately 3.5 times higher than that of the corresponding non-transformed culture. Free radical scavenging DPPH˙ and ABTS˙ assays showed 2.9-fold and 1.76-fold higher anti-oxidant activity in transformed root culture as compared to non-transformed.

Lycium schweinfurthii is a Mediterranean wild shrub rich in plant secondary metabolites. In vitro propagation of this plant may support the production of valuable dietary supplements for humanity, introduction of it to the world market, and opportunities for further studies. The presented study aimed to introduce an efficient and reproducible protocol for in vitro micropropagation of L. schweinfurthii and assess the genetic stability of micropropagated plants (MiPs) as well as to estimate phenolic, flavonoid, ferulic acid contents, and the antioxidant activity in leaves of micropropagated plants. Two DNA-based techniques, random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR), and one biochemical technique, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), were used to assess the genetic stability in MiPs. Spectrophotometric analysis was performed to estimate total phenolic and flavonoid contents and antioxidant activity of MiPs leaves, while ferulic acid content was estimated using high-performance thin-layer chromatography (HPTLC). Sufficient shoot proliferation was achieved at MS (Murashige and Skoog) medium supplemented with 0.4 mg L−1 kinetin and rooted successfully on half-strength MS medium fortified with 0.4 mg L−1 Indole-3-butyric acid (IBA). The Jaccard’s similarity coefficients detected in MiPs reached 52%, 55%, and 82% in the RAPD, ISSR, and SDS-PAGE analyses, respectively. In the dried leaves of MiPs, the phenolic, flavonoid, and ferulic acid contents of 11.53 mg gallic acid equivalent, 12.99 mg catechin equivalent, and 45.52 mg were estimated per gram, respectively. However, an IC50 of 0.43, and 1.99 mg mL−1 of MiP dried leaves’ methanolic extract was required to scavenge half of the DPPH, and ABTS free radicals, respectively. The study presented a successful protocol for in vitro propagation of a valued promising plant source of phenolic compounds.