Search Results (7)

(1) Background: Traditionally, hop is propagated using rhizome fragments or herbaceous stem cuttings. Micropropagation, therefore, offers a viable alternative for the large-scale production of healthy, genetically uniform plants, regardless of the season and within confined spaces. A temporary immersion system (TIS) facilitates plant propagation by alternating immersions of microcuttings in liquid culture medium with dry periods, preventing gas accumulation through forced ventilation. (2) Methods: In this study, the response of hop plantlets, cv. Columbus, cultured in media with and without sucrose, in solid and liquid culture systems (Plantform^TM bioreactor), was evaluated, considering its effect on morpho-physiological parameters, on the total phenolic content, and on antioxidant capacity. Moreover, to make the TIS more efficient, the effect of immersion duration (three and six minutes every twelve hours) was evaluated. (3) Results: The presence of sucrose in the culture medium improved plant proliferation in both culture systems tested: solid and liquid (particularly for explants immersed for three minutes). In the TIS, plantlets with a higher antioxidant capacity were obtained when sucrose-free culture medium was used. (4) Conclusions: This study confirms the efficacy of the TIS as a hop propagation method but also as a valid tool to produce biomass to be used as a source of bioactive compounds. Full article

Ruta corsica is a rare and endemic plant native to Corsica. Due to its limited distribution and the priority to preserve natural sites, has been insufficiently studied. In vitro cultures provide an opportunity to research R. corsica under controlled conditions. In the present study, in vitro cultures of R. corsica were conducted in Plantform^TM bioreactors. The study aimed to assess the effects of growth cycle length (5 and 6 weeks) and different concentrations of plant growth regulators (NAA and BAP) at 0.1/0.1, 0.1/0.5, 0.5/0.5, 0.5/1.0, and 1.0/1.0 mg/L on biomass growth and secondary metabolite accumulation. HPLC analysis identified compounds in the furanocoumarin and furoquinoline alkaloid groups, with furanocoumarins being the primary secondary metabolites (maximum total content: 1571.5 mg/100 g DW). Among them, xanthotoxin, psoralen, and bergapten were dominant, with maximum concentrations of 588.1, 426.6, and 325.2 mg/100 g DW, respectively. The maximum total content of furoquinoline alkaloids was 661 mg/100 g DW, with γ-fagarine as the primary metabolite, reaching 448 mg/100 g DW. The optimal conditions for secondary metabolite accumulation in R. corsica cultures were a 5-week growth cycle and the LS 0.1/0.1 medium variant. Full article

Sundews (Drosera sp.) are the source of biologically active secondary metabolites: phenolic acids, flavonoids, and 1,4-naphtoquinones. Because obtaining them from the natural environment is impossible (rare and endangered species), in this study modifications of traditional tissue cultures grown in solid medium (SM), such as agitated cultures (ACs) (cultures in liquid medium with rotary shaking) and temporary immersion bioreactors Plantform^TM (TIB), were used for multiplication of four sundew species: Drosera peltata, Drosera indica, Drosera regia, and Drosera binata, with simultaneously effective synthesis of biologically active phenolic compounds. Each species cultivated on SM, AC, and TIB was tested for biomass accumulation, the content of total phenols and selected phenolic derivative concentrations (DAD-HPLC), the productivity on of phenolic compounds, as well as its antibacterial activity against two human pathogens: Staphylococcus aureus and Escherichia coli. The results showed that the type of culture should be selected for each species separately. Phytochemical analyses showed that the synthesis of secondary metabolites from the groups of phenolic acids, flavonoids, and 1,4-naphthoquinones can be increased by modifying the cultivation conditions. D. regia turned out to be the richest in phenolic compounds, including 1,4-naphtoquinones: plumbagin and ramentaceone. Extracts from D. indica and D. regia tissue showed strong antibacterial activity against both pathogens. It has also been shown that the growth conditions of sundews can modify the level of secondary metabolites, and thus, their biological activity. Full article

The propagation of Crocus sativus L. relies exclusively on corm multiplication. As underground storage organs, corms are susceptible to a wide range of pathogens, environmental stresses, and diseases, making traditional propagation methods often ineffective with the loss of valuable material. In vitro propagation offers an alternative for the saffron culture under controlled conditions. In particular, the innovative application of the Temporary Immersion System (TIS) represents a technological advancement for enhancing biomass production with a reduction in operational costs. The current study utilized the Plantform™ bioreactor to propagate in vitro saffron corms from the ‘Abruzzo’ region (Italy), integrating machine learning models to assess its performance. The evaluation of saffron explants after 30, 60, and 90 days of culture showed a marked improvement in growth and microcorm production compared to conventional in vitro culture on semisolid medium, supported by the machine learning analysis. Indeed, the Random Forest algorithm revealed a predictive accuracy with an R² value of 0.81 for microcorm number, showcasing the capability of machine learning models to forecast propagation outcomes effectively. These results confirm that applying TIS in saffron culture could lead to economically viable, large biomass production within a controlled environment, irrespective of seasonality. This study represents the first endeavor to use TIS technology to enhance the in vitro propagation of saffron in conjunction with machine learning, suggesting an innovative approach for cultivating high-value crops like saffron. Full article

The present work focuses on in vitro cultures of Ruta montana L. in temporary immersion Plantform^TM bioreactors. The main aim of the study was to evaluate the effects of cultivation time (5 and 6 weeks) and different concentrations (0.1–1.0 mg/L) of plant growth and development regulators (NAA and BAP) on the increase in biomass and the accumulation of secondary metabolites. Consequently, the antioxidant, antibacterial, and antibiofilm potentials of methanol extracts obtained from the in vitro-cultured biomass of R. montana were evaluated. High-performance liquid chromatography analysis was performed to characterize furanocoumarins, furoquinoline alkaloids, phenolic acids, and catechins. The major secondary metabolites in R. montana cultures were coumarins (maximum total content of 1824.3 mg/100 g DM), and the dominant compounds among them were xanthotoxin and bergapten. The maximum content of alkaloids was 561.7 mg/100 g DM. Concerning the antioxidant activity, the extract obtained from the biomass grown on the 0.1/0.1 LS medium variant, with an IC₅₀ 0.90 ± 0.03 mg/mL, showed the best chelating ability among the extracts, while the 0.1/0.1 and 0.5/1.0 LS media variants showed the best antibacterial (MIC range 125–500 µg/mL) and antibiofilm activity against resistant Staphylococcus aureus strains. Full article

Peanuts (Arachis hypogaea L.) are a rich source of herbal oil, proteins, minerals, vitamins, fibers, essential amino acids, as well as bioactive compounds, and are thus widely used for human nutrition and animal feed, and for prevention from certain diseases. However, the in vitro regeneration response of the species is generally low, and it also displays a significant variability among its varieties. Thus, the development of advanced protocols and approaches for the in vitro propagation of peanut is still of immense importance. A recently developed in vitro propagation technique, TIS; Temporary Immersion Bioreactor System, provides a new approach for the mass propagation of plants. Accordingly, the present study provides an efficient de novo regeneration protocol for Arachis hypogaea L. cv. Virginia by using a TIS. Different concentrations of cytokinins, i.e., benzyladenine (BA) or thidiazuron (TDZ), were tested with several combinations of dry and medium immersion periods of TIS, corresponding to a total of 8, 12, 16, 24, 32, 36, 48, 64, 72, and 96 min daily immersions for the induction of direct organogenesis. The study exhibited that an MS medium added to 110 µM BA or 10 µM TDZ are the most appropriate medium formulations in TIS, when applied for 16 min every 16 h. The application of optimized procedures to cv. NC7 and two valuable Turkish autochthonous varieties, 7 × 77 and Com74, is also reported. To the best of our knowledge, the present study draws attention also for being the first study in which a TIS was used for peanuts. Full article

Goji (Lycium barbarum L.) has recognized nutritive and antioxidant properties and many products are commercialized for health in food market. Besides its food use, goji has been the subject of more than 2000 years of traditional Chinese medicine, using berries, root bark, and leaves. Here, the potential of the liquid culture in temporary immersion system (TIS) by using the bioreactor Plantform^TM was tested for the large-scale production of high-quality goji shoots and the subsequent production of total phenols and flavonoids. The three tested immersion cycles differently influenced the shoot quality in terms of proliferation and hyperhydricity. The best immersion cycle (time and frequency) was proven to have the shortest daily immersion time (6 min every 24 h) which ensured good levels of relative growth and multiplication rate, very limited onset of hyperydricity, and the longest shoots, promoting direct rooting after only 30 days of culture. In comparison with the semisolid culture, the TIS culture resulted in an increase of the total phenolic content (TPC) and in a lower value of the total flavonoid content (TFC). However, considering the higher quantity of biomass produced in the Plantform^TM bioreactor, the difference in terms of TFC productivity between semisolid medium and TIS liquid culture was proven to be statistically equivalent. Full article