Saffron (Crocus sativus L.) PROTOPLASTS were isolated from the cells of a suspension culture or calli with a solution of Cellulase, Pectinase and Hemicellulase and embedded in Ca-alginate beads. They were cultured with or without nurse cells in MS medium supplemented with 2,4-D and 6- benzylaminopurine at 25°C. After several changes of medium, cell-clusters appeared on the surface of the Ca-alginate beads. The PROTOPLASTS without immobilization in Ca-alginate beads did not display cell division. Furthermore, growth of cell clusters in the medium with nurse cells was much better than in the medium without nurse cells. Then, the beads were transferred onto MS agar medium supplemented with 1-naphtalene acetic acid and 6-benzylaminopurine and cultured at 15°C or 20°C. After 3-4 months of culture, great calli were observed on the surface of the beads. The regenerated shoots were obtained approximately 6-7 months after protoplast isolation. The critical factors seem to be associated with the quality of the culture, enzyme composition and concentration used for protoplast isolation.

Background: In Algeria, date palm is currently confronted to the Bayoud disease. Biotechnological tools such as PROTOPLASTS fusion can appear as an alternative to ensure rapid multiplication and improvement of this species.Objectives: Callogenesis induction in PROTOPLASTS isolated from embryogenic callus of three date palm cultivars.Materials and Methods: Some factors influencing the isolation and culture of PROTOPLASTS segregated from the calli of three date palm (Phoenix dactylifera L.) cultivars (Deglet Nour, Akerbouch and Degla Beida) were studied. PROTOPLASTS of each cultivar were cultured on a semi-solid medium supplemented with various hormonal balances.Results: Maceration with an enzymatic solution containing 1.5% cellulase and 1% macerozyme R10 in the presence of 0.5 M mannitol for more than 16 h with gentle agitation allows isolation of a great number of viable PROTOPLASTS. In addition, purification of PROTOPLASTS on a cushion of 21 or 25% sucrose was effective in cell debris removal and maximum recovery. The culture of isolated PROTOPLASTS on a semi-solidified Murashige and Skoog medium, with 0.3% agarose, 2 mg. L-1 2, 4-D and 0.5 mg.L-1 BAP allowed good viable protoplast maintenance as well as cell wall regeneration. After more than two months of culture, cell divisions were still occurring and microcalli became visible to the naked eye, containing a large number of cells.Conclusions: The developed protocol can be useful for application of somatic hybridization to improve date palm cultivars.

The use of in vitro potato shoot cultures for protoplast isolation is desirable for consistent protoplast qualities. Ethylene build-up in the culture vessels causes problems for leaf growth (e.g. decreasing leaf surface, dry weight and chlorophyll) in shoot culture. Fifty to one hundred یM Silver thiosulfate (STS) produced a larger leaf area as a source of plant material for protoplast isolation. STS also decreased the internode length of potato shoots but increased dry weight and chlorophyll. Regenerated plants were obtained from cultured PROTOPLASTS in a series of media based on the MS medium. PROTOPLASTS of Delaware showed a better response in cell division and colony formation in agarose-solidified culture medium. Regenerated plants showed some degrees of aneuploid but basically were similar to the original potato plants.

An efficient system has been developed for the reproducible regeneration of plants from cell suspension-derived PROTOPLASTS of the two commercial Iranian Japonica rice cultivars Tarom and Khazer. Friable embryogenic calli were used for cell suspension initiation and PROTOPLASTS were isolated from both varieties. When embedded in agarose, PROTOPLASTS failed to divide. However, sustained divisions were obtained by using nurse cells of Lolium moltiflorum. Plant regeneration was 21.1% and 10.5% for Tarom and Khazer, respectively. Somaclonal variation was observed amongst regenerated plants, 16.2% of regenerants were tetraploid, and the rest were diploid.

Background: The rise of opportunistic fungal infections highlights the need for development of new antimicrobial agents. Antimicrobial Peptides (AMPs) and Antifungal Peptides (AFPs) are among the agents with minimal resistance being developed against them, therefore they can be used as structural templates for design of new antimicrobial agents.Methods: In the present study four antifungal peptidomimetic structures named C1 to C4 were designed based on plant defensin of Pisum sativum.Minimum inhibitory concentrations (MICs) for these structures were determined against Aspergillus niger N402, Candida albicans ATCC 10231, and Saccharomyces cerevisiae PTCC 5052.Results: C1 and C2 showed more potent antifungal activity against these fungal strains compared to C3 and C4. The structure C2 demonstrated a potent antifungal activity among them and could be used as a template for future study on antifungal peptidomemetics design. Sequences alignments led to identifying antifungal decapeptide (KTCENLADTY) named KTC-Y, which its MIC was determined on fungal protoplast showing 25 (mg/ml) against Aspergillus fumigatus Af293.Conclusion: The present approach to reach the antifungal molecules seems to be a powerful approach in design of bioactive agents based on AMP mimetic identification.