Application of d cryo-plate technique for the cryopreservation of in vitro-grown shoot tips of Tarenaya spinosa (Cleomaceae)

BACKGROUND

Tarenaya spinosa is a medicinal species used for treating respiratory and inflammatory diseases. Various biotechnological studies have been developed for in vitro establishment of plants and long-term conservation of this species.

OBJECTIVE

This study aimed to establish a new cryopreservation protocol using the D cryo-plate technique for in vitro-grown shoot tips of T. spinosa.

MATERIALS AND METHODS

Different steps of the cryopreservation procedure were evaluated in this work: preculture; sucrose concentration of calcium alginate gel; concentration and time of exposure to osmoprotective loading solution; time of exposure to silica gel; and regrowth on recovery medium.

RESULTS

The optimal procedure included preculture with increasing sucrose concentration (from 0.25 to 0.50 M), encapsulation and dehydration over silica-gel for 60 min. Increasing sucrose concentration in the loading solution or exposure duration had a negative effect on recovery of cryopreserved shoot tips. However, the association of calcium alginate gel enriched with 0.6 M sucrose with post-rewarming culture with BAP for 2 weeks resulted in the most efficient cryopreservation protocol (76% survival and 70% shoot recovery).

CONCLUSION

The plants developed after cryopreservation maintained their in vitro multiplication capacity and demonstrated the efficiency of long-term conservation by D cryo-plate technique for T. spinosa. Doi.org/10.54680/fr23610110512.

Cryopreservation of In Vitro-Grown Shoot Tips of the Medicinal Species Cleome Spinosa (Cleomaceae) Applying Vitrification-Based Techniques

BACKGROUND

Few cryopreservation studies have been reported with the genus Cleome. Due to the use of C. spinosa in traditional medicine and its valuable pharmacological potential, the long-term conservation of the species will allow the safe maintenance of its germplasm.

OBJECTIVE

This study compares two vitrification-based techniques on the cryopreservation of shoot tips of C. spinosa.

MATERIALS AND METHODS

The effect of sucrose preculture and different vitrification solutions was evaluated using vitrification and V Cryo-plate techniques. The supplementation of recovery medium with BAP was also assessed.

RESULTS

The V Cryo-plate proved to be the most efficient technique. Treatment of shoot tips with PVS2 at 0°C resulted in a higher regeneration response after cryopreservation when compared to treatment with PVS2 and PVS3 at 25°C. The highest survival (83.3%) and recovery (76.6%) were achieved for shoot tips exposed to PVS2 for 90 min at 0°C and recovered on MS medium supplemented with 0.5 mg L^-1 BAP for 2 weeks.

CONCLUSION

Plants regenerated from cryopreserved shoot tips maintained their in vitro multiplication capacity and showed a normal phenotypic aspect, demonstrating the efficiency of the cryopreservation protocol.

CRYOPRESERVATION OF ADVENTITIOUS ROOTS OF Cleome rosea Vahl (CLEOMACEAE) USING A VITRIFICATION TECHNIQUE AND ASSESSMENT OF GENETIC STABILITY

BACKGROUND

Cleome rosea, a Brazilian native species, has medicinal potential. Previously a cryopreservation protocol for in vitro roots using the vitrification solution PVS2 has been developed. However, the genetic stability of the cryopreserved material is yet to be assessed.

OBJECTIVES

To evaluate the effects of loading and vitrification solutions (PVS2 and PVS3) on post-cryopreservation recovery of C. rosea roots, and to assess their genetic stability using Random Amplified Polymorphic DNA (RAPD) markers.

MATERIALS AND METHODS

Root segments were pretreated with increasing concentrations of sucrose (0.2 to 0.4 M), followed by osmoprotection with loading solution and treatment with one of the vitrification solutions tested. RESULTS: The highest recoveries using PVS2 and PVS3 were obtained when root segments were exposed to these solutions for 15 min, reaching 77% and 100% respectively. The RAPD band profiles were monomorphic with most of the primers used. This molecular analysis revealed high genetic similarity (similarity coefficients among 0.98 and 1.00) between the cryopreserved roots and their mother plants. CONCLUSION: Roots from in vitro-propagated plants of C. rosea, were successfully cryopreserved using the vitrification technique. No major variations were observed on the genetic stability of cryopreserved roots, validating the use of this protocol as an efficient long-term conservation option for this species.

Susceptibility of Giardia lamblia to Hovenia dulcis extracts

Giardia lamblia is the causative agent of giardiasis, a common parasitic infection of the human and animal digestive tract. Although several drugs have been available to treat this infection, they present unpleasant side effects or cytotoxicity. In order to find a more natural treatment for the disease, we analyzed the effects of the methanolic extract and three fractions obtained from Hovenia dulcis Thunb. (Rhamnaceae) leaves on G. lamblia. Comparing all fractions, dichloromethane was more efficient in reducing Giardia growth. The exposition of G. lamblia to this fraction lead to degenerations in the surface, modifications in the cell shape and alterations in the localization of nuclei. Besides that, the adhesion of G. lamblia was also altered. Experiments revealed that the obtained fraction did not present cytotoxic effects in mammalian cells. In summary, dichloromethane fraction has strong antigiardial effects and could become an important new substance for the treatment of giardiasis.