Percentage Of Regeneration Research Articles

Development of a Protocol for In-vitro Regeneration of Stevia rebaudiana Bertoni

The experiment was conducted to find out an effective combinations and concentrations of plant growth regulators for in vitro regeneration of Stevia rebaudiana Bertoni, a medicinally important, zero-calorie value, sweet tasted and an antidiabetic herb. Murashige and Skoog (MS) medium supplemented with different concentrations and combinations of BAP and NAA were used for shoot regeneration using shoot tip as explant. The highest shoot regeneration percentage (83.33%) was obtained from the MS medium supplemented with 1.0 mg/l BAP + 2.0 mg/l NAA followed by 72.92% of shoot regeneration from MS medium supplemented with 3.0 mg/l BAP + 3.0 mg/l NAA. The lowest percentage (29.17%) of shoot regeneration was observed in MS medium with 0 mg/l BAP + 1.0 mg/l NAA. Significant numbers of healthy and vigorous shootlets were proliferated showing normal phenotypes. The in vitro proliferated shoots were inoculated on MS medium supplemented individually with 0, 1.0, 6.0 mg/l IBA for root initiation. Among the treatments used for root initiation, the highest percentage (75%) of root formation was observed in MS medium supplemented with 6 mg/l IBA + 1.0 mg/l BAP + 2.0 mg/l NAA followed by 71.43% in MS medium with 6 mg/l IBA + 3.0 mg/l BAP + 3.0 mg/l NAA. In contrast, the lowest percentage (14.28%) of root formation was obtained in MS medium supplemented with 6 mg/l IBA + 0 mg/l BAP + 1.0 mg/l NAA. For mass production of healthy Stevia plantlets, MS media supplemented with 1.0 mg/l BAP + 2.0 mg/l NAA, in combination with MS media supplemented with 6 mg/l IBA + 1.0 mg/l BAP + 2.0 mg/l NAA could be used for further proliferation of the plantlets for commercial purpose.

Pulp regeneration using a peptide nanofiber artificial scaffold on animal models: A preliminary study.

In regenerative endodontic procedures (REPs), it is crucial to find effective materials. This study introduces glycosaminoglycan (GAG) mimetic peptide amphiphile (PA, GAG-PA) and K-PA nanofibers, synthesized to emulate sulfated GAGs, aiming to enhance tissue repair within damaged pulp - an area where standardized protocols are currently lacking. The objective of this study was to investigate the regenerative potential of GAG-PA nanofibers in REP. Heparan sulfate mimicking PAs was designed to develop a bioactive nanofibrous supramolecular system. The cavities on the mesial surfaces of the first upper molars of 8 rats (4 rats in the study group and 4 in the control group) were prepared, and the pulps were perforated. Then, the material was applied onto the dental pulp, and the cavities were closed with a self-curing glass ionomer cement filling material. Physiological saline was used in the control group. Thirty days after application, the teeth were extracted, and the formation of regenerative tissue sections in the pulp was evaluated using hematoxylin and eosin (H&E) staining and Masson's trichrome staining. After 30 days, H&E staining demonstrated robust tissue regeneration in the implanted region, with minimal neutrophil infiltration. Masson's trichrome staining confirmed reparative dentin formation. Quantitative analysis revealed a regeneration percentage of 85% in the study group, compared to 80% in the control group. Statistical analysis showed no significant difference in regeneration between the groups (p > 0.05). Our comprehensive study, utilizing GAG-PA and K-PA nanofibers, demonstrated successful synthesis, characterization and formation of nanofiber networks. The in vivo experiment with rats exhibited substantial tissue regeneration with quantifiable results supporting the efficacy of the nanofiber approach. Statistical analysis confirmed the consistency between the study and control groups, emphasizing the potential of these nanofibers in endodontic tissue regeneration applications.

A Novel Solid Media-Free In-Planta Soybean (Glycine max. (L) Merr.) Transformation Approach.

Soybean's lengthy protocols for transgenic plant production are a bottleneck in the transgenic breeding of this crop. Explants cultured on a medium for an extended duration exhibit unanticipated modifications. Stress-induced somaclonal variations and in vitro contaminations also cause substantial losses of transgenic plants. This effect could potentially be mitigated by direct shoot regeneration without solid media or in-planta transformation. The current study focused primarily on developing a rapid and effective media-free in-planta transformation technique for three soybean genotypes (Wm82) and our newly developed two hybrids, designated as ZX-16 and ZX-3. The whole procedure for a transgenic plant takes the same time as a stable grown seedling. Multiple axillary shoots were regenerated on stable-grown soybean seedlings without the ectopic expression of developmental regulatory genes. An approximate amount of 200 µL medium with a growth regulator was employed for shoot organogenesis and growth. The maximal shoot regeneration percentages in the Wm82 and ZX-3 genotypes were 87.1% and 84.5%, respectively. The stable transformation ranged from 3% to 8.0%, with an average of 5.5%. This approach seems to be the opposite of the hairy root transformation method, which allowed transgenic shoots to be regenerated on normal roots. Further improvement regarding an increase in the transformation efficiency and of this technique for a broad range of soybean genotypes and other dicot species would be extremely beneficial in achieving increased stable transformation.

Androgenesis in vitro in anther culture of bread winter wheat

Aim. Study of the effectiveness of stages of in vitro androgenesis in anther culture for the creation of dihaploid lines of bread winter wheat. Methods. In vitro culture of isolated wheat anthers. For each genotype, the following parameters of androgenesis in vitro were determined: the percentage of caluses and the percentage of regeneration of green plants from the number of planted anthers; the percentage of acclimatized plants from regenerated green plantlets, as well as the percentage of fertile (doubled haploid) plants. Results. Androgenesis in vitro in the anther culture of 105 genotypes of soft winter wheat of different genetic origin was studied. Differences regarding the frequency of callusogenesis induction (from 0.17 to 21.25 percent of planted anthers) and the ability to regenerate plants (from 0 to 4.94 percent of planted anthers) were found. The dihaploid lines in anther culturefor almost 50 % of the studied genotypes were obtained. Spontaneous diploidization averaged 29.41 % of the obtained regenerants. Conclusions. Genotype-specific morphogenetic reactions of bread winter wheat microspores in the process of in vitro androgenesis were revealed. 122 dihaploid lines of bread winter wheat were obtained.

Effect of salt stress on plant regeneration efficiency in primed and non-primed seed's calli of rice (Oryza sativa L.) variety Swarna.

This study leads with the primed seeds of rice (var. Swarna) with distilled water (D.W.) and various concentrations of Mg(NO3)2 (0-8mM)/Kinetin (0-5ppm) alone or in combination with screen out the regeneration medium induced tolerance level of NaCl. To fulfill the objective, the primed and non-primed rice seeds were inoculated in MS medium supplemented with 30gL-1 maltose + 1gL-1 casein hydrolysate and 2mgL-1 of 2,4-D for callus induction and cultured up to 45days in two sets: one set for regeneration purpose in NaCl-induced regeneration medium and another set was used to study the physiological potentiality of the callus. The 45-day-old calli were transferred into regeneration medium MSR (MS medium for regeneration) (BAP: NAA: Kinetin = 4:1:1) containing NaCl with a concentration range of 0 to 300mM. The number of regenerating calli and shoot regeneration percentage, number of plantlets obtained from one callus, recovery of plantlets from each concentration of NaCl and proline estimation from the leaf of the regenerated plantlets were determined from one set obtained after 45days. The calli obtained from another set after 45days, the frequencies of total and embryogenic calli induction percentage, fresh and dry weights, proline content, nitrate reductase and superoxide dismutase activities were measured. The calli obtained from 2.5ppm kinetin + 4mMMg(NO3)2 primed seeds were showed best result as compared to the other treatments for the above-mentioned parameters in different concentrations of NaCl-induced medium and survive up to 200mM concentrations of NaCl.

Preserving Nature’s Treasure: A Journey into the In Vitro Conservation and Micropropagation of the Endangered Medicinal Marvel—Podophyllum hexandrum Royle

Podophyllum hexandrum Royle, also known as Podophyllum emodi Wall, holds significant ecological, ornamental, and medicinal values. However, it has become endangered due to overexploitation, prolonged seed dormancy, slow natural regeneration, and climate change. This study developed an efficient in vitro protocol for callogenesis and micropropagation of P. hexandrum to conserve germplasm in in vitro conditions. Callus formation from various plant parts, including the leaf, stem, rhizome, radicle, and cotyledon, was induced using Murashige and Skoog (MS) medium supplemented with different plant growth regulators. The combination of benzyladenine at 1 mg L−1 and 4-dichlorophenoxy acetic acid at 3 mg L−1 was optimal for biomass production, yielding 215.88 ± 0.31 mg, with growth per gram at 8.32 ± 0.32 and a growth rate of 13.62 ± 0.25 mg/day on MS medium. For shoot proliferation, benzyladenine (3.5 mg L−1) and naphthalene acetic acid (0.5 mg L−1) combined with activated charcoal showed the highest shoot induction percentage per explant. For shoot regeneration from calluses, 6-benzylaminopurine (0.5 mg L−1) and thidiazuron (2 mg L−1) were most effective, producing superior shoot length, number of regenerations, and regeneration percentage. Root induction was successful with α-naphthalene acetic acid supplementation (0.5 to 1.5 mg L−1) in MS medium, resulting in the highest number per explant (4.08 ± 0.08), length (5.45 ± 0.15 cm), and rooting rate (87.00 ± 1.66%) of roots in plantlets. Subculturing for callus culture was performed every 28 days for up to four subcultures to prevent nutrient depletion and toxic metabolite accumulation, ensuring tissue health and viability. Continuous subculturing of callus on MS medium maintained healthy P. hexandrum germplasm in vitro. Overall, this micropropagation protocol provides a rapid system for conserving P. hexandrum germplasm.

Optimalisation of in vitro sterilisation methods for North Sumatra local garlic (Allium Sativum L.)

Abstract The establishment stage is critical to the success of plant tissue culture. Each plant tissue has unique tissue surface characteristics that interact with various natural microbes. The goal of this study was to find a sterilisation method that is effective at removing contamination while not damaging or inhibiting explant regeneration. In this study, Completely Randomized Design (CRD) factorial with 2 factors was used. The first factor was the disinfectant, namely T1 (Benzalkonium chloride 0.5%), T2 (Nordox 6 g/L 0.6%), and T3 (Clorox 10%). The second factor is the type of media, consisting of M1 (BDS supplemented with 1.8 μM/L 2,4-D and 9.2 μM/L Kinetin), M2 (BDS supplemented with 9 μM/L 2,4-D and 9.2 μM/L Kinetin), M3 (MS supplemented with 9 μM/L 2,4-D and 4.6 μM/L Kinetin), and M4 (MS media supplemented with 1.3 μM/L 2,4-D and 9.2 μM/L Kinetin. The observed parameters were the percentage of contamination, the survival rate, the type of contamination, the percentage of callus growing, weight and diameter. The T2 treatment was the most effective in reducing contamination and had the highest survival rate. T3 treatment resulted in the highest callus regeneration percentage, callus weight, and callus diameter, but also the highest level of contamination.

Optimization of the in-vitro culture protocol of Haworthiopsis viscosa and Haworthia truncata var. truncata

This study was conducted to optimize the in vitro culture of Haworthiopsis viscosa and Haworthia truncata var. truncate. The full and half concentration of Murashige and Skoog (MS) and Gamborg (B5) after the disinfection of the explants was used to determine the suitable medium culture. The effect of the different concentrations of 6-benzyl aminopurine (BA) and Kinetin (Kin) (0, 1, 2, 3 and 6 mg/L) was investigated on the percentage of regeneration, callus formation and the number of seedlings regenerated. The different concentrations of indole-3-butyric acid (IBA) and 1-naphthaleneacetic acid (NAA) (0, 0.5, 1 and 1.5 mg/L) were used to investigate the seedlings rooting. Finally, the cocopeat + perlite, the sand +perlite and the vermicolit +perlite substrates were studied to determine the suitable substrate for compatibility. The results show that the use of MS culture medium at complete concentration was more successful than the other treatments and increased the regeneration and seedling percentage in both species. Also, the use of BA at a concentration of 1 mg/L (H. truncata var. truncate) and at a concentration of 3 mg/L (H. viscosa) increased the percentage of regeneration and the number of regenerated seedlings significantly and the regenerated seedlings had a very good quality. The rooting of seedlings in both studied species was the highest at 1 mg/L IBA. The use of NAA in the culture medium produced roots that stuck together and were fragile in some cases, which was not suitable for the compatibility. By comparing different substrates, it was found that the use of cocopeat + perlite increased the seedling compatibility percentage to more than 95% in both species.

High stability and selectivity of butterfly pea flower extract-NiAl LDH-based catalysts in the tetracycline degradation.

Layered double hydroxide (LDH) is an applicable material that can be modified in various ways. Modifications using natural extracts fulfill the principles of "green chemistry." The preparation of butterfly pea flower extract (BPE)-modified NiAl LDH was completed using the calcination and restacking method. The characteristics of the prepared composites were identified through analysis of functional groups, crystal phase, bandgap energy, surface area and surface morphology. Fourier transform-infrared (FT-IR) characterization revealed that the active group of the catalyst is -OH except for NiAl layered double oxide (LDO), which has the metal oxide-like functional groups. X-ray diffraction patterns expressed a typical layered material structure of NiAl LDH dan NiAl LDH-BPE, but not for NiAl LDO and NiAl LDO-BPE. Introducing BPE into NiAl LDH and NiAl LDO effectively decreased the bandgap energy and changed the surface morphology. The prepared catalysts were applied in a batch system with pH 5 to degrade tetracycline (TC). NiAl LDO demonstrated the highest activity as a catalyst in TC degradation, with a 93.61% degradation rate. In contrast, NiAl LDO-BPE demonstrated the highest structural stability in TC degradation and repeated use, with an initial degradation percentage of 82.58% and a fifth regeneration percentage of 71.4%.

An efficient in vitro organogenesis protocol for the endangered relic tree species Bretschneidera sinensis and genetic fidelity assessment using DNA markers.

Bretschneidera sinensis is a monotypic species of rare and tertiary relic trees mainly distributed in China. B. sinensis is a potentially valuable horticultural plant, which has significant ornamental and research value, and is a crucial tool for the study of phylogeography. The artificial cultivation of B. sinensis is of great scientific value and practical significance. In this study, we developed a direct organogenesis process of B. sinensis using mature zygotic embryos as initial materials. The highest sterile germination induction (54.5%) from the mature zygotic embryo was obtained in a Murashige and Skoog (MS) medium with 2.0 mg·L-1 6-benzylaminopurine (6-BA) and 0.2 mg·L-1 α-naphthaleneacetic acid (NAA). The highest percentage of shoot regeneration (90.37%) was attained using 1.0 mg·L-1 6-BA and 0.01 mg·L-1 NAA in the MS medium. The Woody Plant Medium (WPM) had the greatest adventitious shoot elongation rate of 93.33%. The most optimized rooting rate was 88.89% in a half-strength MS medium containing 2.0 mg·L-1 indole-3-butyric acid (IBA) and 1.0 mg·L-1 NAA. The genetic fidelity of in vitro regenerated plantlets was assessed using inter-simple sequence repeats and random amplified polymorphic DNA molecular markers, confirming the genetic uniformity and stability of regenerated B. sinensis plantlets. Our research presents an effective in vitro propagation system for B. sinensis, laying the groundwork for its germplasm conservation and large-scale production while maintaining high genetic integrity.

Simulacija oštećenja od grada na regeneraciju i prinos soje (Glycine max (L.) Merr.)

The most common mechanical damage to soybean in the agroecological conditions of Serbia occurs after the appearance of hail, floods or due to damage from wild animals and insects. In recent years, extreme temperatures accompanied by drought have been increasingly recorded during the summer months, as well as the appearance of hail, which has become frequent during the growing season of spring crops. The aim of this work was to determine the consequences and the extent of yield reduction if hail occurs in the generative stages of soybean development. The occurrence of hail in the R1 (beginning bloom) and R3 (beginning pod) stages of development in the form of plant damage was simulated. This paper will present the results of how three soybean varieties reacted after simulated hail damage in two stages of generative development and what the effects were on yield, height, number of fertile nodes, as well as percentage of plant regeneration. The trial was set up in 2020 as a two-factorial experiment in three replications. Three soybean varieties were sown in late April. In order to simulate hail damage, the plants were cut to a height of 15 cm to ensure at least two nodes and enable the regeneration of the plants. The stage of development of soybean, i.e. the moment of hail damage, had a direct impact on the yield, the number of regenerated plants, as well as the number of fertile nodes.

Evidence of efficient in vitro micropropagation from bulb scales of starch grape hyacinth (Muscari neglectum Guss. Ex. Ten.)

Muscari neglectum is a widespread plant species that grows in various areas of the Mediterranean region in the wild. The species has a high potential for use as cut flowers, outdoor or indoor ornamental or garden plants. It is also used as a food, and forage plant on limited scales in rural areas. There is a lack of commercial production protocols for M. neglectum. The development of a fast and efficient protocol for commercial production, may contribute to the economy of T?rkiye and improve local people?s quality of life. Therefore, this study aimed to develop safe in vitro vegetative propagation techniques using 2, 3, 4, and 5 bulb scale explants on MS medium using 1 mg BAP L-1 + 0.00, 0.40, 0.60, 0.80, 1.00,1.20 mg NAA L-1. Any number of bulb scale explants obtained from freshly harvested bulbs were not suitable for micropropagation and developed necrosis. However, any number of bulb scales obtained from 6 weeks of waiting for bulbs did not show the problem. A regeneration percentage of 13.33 to 100% was noted on 2-scale explants. Additionally, 100% callus formation was observed on these scales using MS medium containing 1 mg BAP L-1 + 0.8, 1.0, and 1.20 mg NAA L-1 (3 combinations). In addition, 1.93 bulblets with a diameter of 0.97 cm (the largest) were observed on MS medium containing 1 mg BAP L-1 + 0.4 mg NAA L-1. Although, 3, 4, and 5 bulb scale explants induced bulblets in variable numbers, the rate of bulblet induction was not at par with bulblet induction on 2 scale explants. The largest bulblets developed on 2-scale explants were rooted on ? ? MS medium containing 0.5 mg NAA L-1. The results obtained for micropropagation of M. neglectum species are of great importance for the commercial production of the species.

Somatic Embryogenesis and Direct Shoot Bud Formation from in vitro Root Segments of Garlic (Allium sativum L.)

In vitro techniques are unconventionally used for garlic improvement. In garlic tissue culture, numerous roots are produced in vitro. Segments (1 cm) of those in vitro roots were cultivated on MS medium with 5.0 μM 2, 4-D for callus initiation followed by transfer to 0.5 μM 2, 4-D for somatic embryogenesis. Root segments had 51.67% callus and somatic embryo formation. Plantlet regeneration was obtained from 90% calli after being transferred to MS medium supplemented with 5.0 μM kinetin. Within 6 months, 54.8 plants per root segment and 42.2 plants per root tip explant were found. MS media supplemented with 1.0 or 5.0 μM NAA in combination with 10.0 or 50.0 μM BA were used for direct shoot bud induction from root segments. The highest percentage (23.33 %) of direct shoot bud regeneration was found in 5.0 μM NAA with 50.0 μM BA within 2 months. The number of shoots per explant was varied from 1-81 with the highest average of 15.75 shoots per explant. The shoots produced bulblets upon transfer to a medium containing higher amount of sucrose (12%). The largest bulblets weighed 356.57 g in the medium with 5.0 μM NAA and 50.0 μM BA. In both pathways, regeneration occurred from only the apical (distal) end of the root segments. The protocols are promising for continuous regeneration of propagules and genetic transformation study for improvement of garlic. Plant Tissue Cult. & Biotech. 33(2): 135-142, 2023 (December)

Somatic Embryogenesis and Plantlet Regeneration from Immature Embryos of Papaya (Carica papaya L.)

The experiment was carried out in the Laboratory of the Biotechnology Division, Bangladesh Agricultural Research Institute (BARI) to find out embryogenic responses and plantlets regeneration from immature embryos of papaya. The explants were inoculated on Murashige and Skoog (MS) medium supplemented with 0, 36, 45, 54 & 63 μΜ 2, 4-D and incubated in complete darkness at 25°C ± 1°C. Calli were obtained within 3 weeks of culture period. The highest percentage of explants (46.67) produced callus using 2, 4-D at a concentration of 45 μΜ. Calli were then transferred to somatic embryogenesis medium where embryogenic calli were developed, turned into greenish color and these somatic embryos were noticed within 10 days. The highest number of somatic embryos (86.33) was produced per explant on MS containing 54 μΜ 2, 4-D. Somatic embryos were regenerated on MS supplemented with different concentrations and combinations of BAP and NAA including GA3. The maximum regeneration percentage of somatic embryos (intact rooted plantlets) (54.17) was recorded in the medium supplemented with 0.4 μΜ each of BAP and NAA in combination with 10 μΜ GA3. The somatic embryo-derived plantlets were successfully established in small plastic pots with prepared soil and finally transplanted in the field. The plants were grown well and produced fruit under their natural environment. Plant Tissue Cult. & Biotech. 33(2): 97-106, 2023 (December)

Multi-drops and Cross-sections, Efficient Methods for Establishing Cell Suspension Culture of Cuminum cyminum L. and Plant Regeneration

The current study aims of the current study is to establish cell suspension cultures of the medicinal plant, cumin Cuminum cyminum L. by the application of multiple drops and cross-section techniques. These methods were used in cultivating cell suspensions and in vitro plant regeneration. Leaf, stem, hypocotyl and root explants were cultured in Murashige and Skoog (MS) medium containing different concentrations (0.05, 0.5 and 1.0 mg.l-1) of naphthalene acetic acid (NAA) and (0.05, 0.1, 1.0 and 2.0 mg.l-1) benzyl adenine BA for callus production. The results indicated the high response of cumin, as the percentage of callus initiation was 100%.The plant regeneration percentage reached 91.6%. Moreover, a friable callus of hypocotyls was appropriate for initiation of cell suspension culture in MS medium with 0.5mg.l-1 NAA and 1.0 mg.l-1benzyl adenine (BA). The best density for primordial callus formation was 51.0 ×105 cells ml-1 in both multiple-drops and cross-sections embedding methods. Callus that had been produced from multi drops and sectors had the ability for shoot regeneration. This study clarified the efficiency of these techniques in establishing cell suspension culture and shoot regeneration, which could be promising sources for high production of active compounds in cumin plant.

In Vitro Regeneration, Conservation, and Field Evaluation of a Medicinal Plant– Greater Burdock (Arctium Lappa L.)

A suitable micropropagation protocol and ex vitro acclimation method have been developed from in vitro grown seedling explants through cotyledonary node and leaf explants in consideration of the vegetable and medicinal properties of Greater Burdock. MS medium with 0.5-4.0 μM BAP showed highest percentage of axillary shoot regeneration from the cotyledonary nodal explants. Direct shoot regeneration was achieved by culturing 1.0 cm2 sections of about 25 days old leaves of in vitro grown shoot on MS medium enriched with 4.0 μM BAP and 2.0 μM IBA or NAA after 5 weeks of culture. Within six weeks of incubation on medium enriched with 4.0 M BAP and 2.0 M IBA or NAA, the leaf explants also developed callus from the cut margins. The greatest number of adventitious shoots could then be formed from the leaf-derived callus within 10 weeks of culture on the same media mix. More than 20 shoots were formed per callus clump at the third subculture, which had the highest rate of shoot multiplication. A. lappa's shoot and callus were both preserved at 5 ºC in MS medium with 4.0 μM Kn and 2.0 μM IBA, as well as 4.0 μM BAP and 2.0 μM IBA, respectively. The in vitro proliferated and elongated shoots were separated from callus clump for rooting. A root-induction MS medium with 6.0 μM IBA or NAA was used to cultivate the microshoots individually. All of the cultured microshoots generated 2-16 roots within 4 weeks of being moved to the rooting medium. Regenerated plantlets were transferred to vermiculite and successfully established in an ex vivo environment with a 98% survival rate. J. Bio-Sci. 31(1): 1-15, 2023

Enhancing Methylene Blue Dye Removal using pyrolyzed Mytella falcata Shells: Characterization, Kinetics, Isotherm, and Regeneration through Photolysis and Peroxidation.

The potential of pyrolyzed Mytella falcata shells as an adsorbent for removing methylene blue dye molecules from aqueous solutions was investigated. The study found that the adsorbent produced at 600 °C of pyrolysis temperature, with an adsorbent mass of 0.5 g, particle diameter of 0.297-0.149 mm, and pH 12.0, demonstrated the highest dye molecule removal efficiency of 82.41%. The material's porosity was observed through scanning electron microscopy, which is favorable for adsorption, while Fourier-transform infrared spectroscopy and X-Ray diffraction analysis analyses confirmed the presence of calcium carbonate in the crystalline phases. The pseudo-second order model was found to be the best fit for the data, suggesting that the adsorption mechanism involves two steps: external diffusion and diffusion via the solid pores. The Redlich-Peterson isotherm model better represented the equilibrium data, and the methylene blue adsorption was found to be spontaneous, favorable, and endothermic. The hydrogen peroxide with UV oxidation was found to be the most efficient method of regeneration, with a regeneration percentage of 63% achieved using 600 mmol.L-1 of oxidizing agents. The results suggest that pyrolyzed Mytella falcata shells could serve as an ecologically viable adsorbent alternative, reducing the amount of waste produced in the local environment and at the same time removing pollutants from the water. The material's adsorption capacity remained almost constant in the first adsorption-oxidation cycles, indicating its potential for repeated use.

Characteristics of a gill resection – Regeneration model in freshwater laboratory-reared Atlantic salmon (Salmo salar)

Impaired gill function is a critical issue in aquaculture due to factors such as poor water quality, disease, and farm management practices which can greatly compromise gill integrity and ultimately fish growth and survival. Regeneration of damaged gill tissue has been reported for some fish species, however, little is known about Atlantic salmon, which is one of the most economically important salmonid species. This study investigated the regenerative capability of gill tissue following resection in post-smolt Atlantic salmon reared in fresh water. Fish were subjected to two levels of resection severity: 30% or 50% of filament length. Changes in filament length and the cytological and functional capacity of regenerated tissue were studied at several time points post-resection (PR). On average, 38% ± 3.89 of the resected filament length regenerated in both resected groups at week-20 PR. However, absolute regeneration (mm) in 50% resected filaments was greater as compared to the 30% resected filaments. In both groups, regeneration percentage was significantly different among individuals, but was not correlated with initial body size, condition factor, or overall fish growth rate. Immunohistochemistry showed an increase in cell proliferation at the filament tip shortly after resection followed by the appearance of ionocytes, chemoreceptive neuroepithelial cells (NECs), and nerve fibres at week-4 PR. In both resected groups >50% and 90% of NECs were innervated by week-12 and -20 PR, respectively. Gill Na+/K+-ATPase activity in regenerated tissue was not significantly different from that of internal control and non-resected control fish. Our results demonstrate significant regeneration and apparent functional recovery of resected gill filaments in Atlantic salmon which has important implications for recovery from gill damage and developing best practices for maintenance of gill health of farmed salmon.

Propagation, development phases and domestication of <i>Cyperus</i> <i>rotundus</i> L. in the Western Highlands of Cameroon

Cyperus rotundus Linn. is a potentially valuable aromatic plant given its ability to synthesise essential oil and the variety of traditional uses associated with it. The valorisation of this plant would imply the exploitation of a significant quantity of its biomass, which cannot be obtained from the wild. The aim of this study was to determine the best methods for regeneration and the development phases of C. rotundus, in order to ensure the continuous availability of its biomass. The mode of natural regeneration and the state of domestication of C. rotundus by local populations were investigated through surveys of traditional healers and herbalists. In addition, ex situ regeneration trials were carried out using vegetative propagation from bulbs and seed germination. The vegetative propagation was assessed by estimating the lag time and percentage regeneration of the bulbs, while the seed germination percentage was evaluated. The development phases of the plant were identified following the BBCH (Biologische Bundesanstalt Bundessortenamt and CHemische Industrie) scale. The yield was calculated from the underground biomass of the bulbs produced at the end of the plant life cycle. The results showed that C. rotundus regenerates naturally from bulbs and rarely from seeds. In the Western Highlands of Cameroon, traditional practitioners and herbalists have begun domesticating C. rotundus on a small scale. Propagation attempts from seed were unsuccessful in the present study. However, from bulbs, a lag time of 10 days was observed and a regeneration percentage of 88% obtained after 47 days. Five phases of development were identified including emergence (0), bolting (1), flowering (2), maturation (3) and senescence (4). The production of bulbs, which are organs containing the essential oils, was observed from the bolting phase. The biomasses of about 383, 493 and 520 kg/ha were obtained during phase 1, 2 and 3 respectively. The best propagation method and the development phases of Cyperus rotundus investigated in this work could contribute to an advance in the domestication process in order to ensure its availability and sustainability.

Dynamics of Organic Acids during the Droplet-Vitrification Cryopreservation Procedure Can Be a Signature of Oxidative Stress in Pogostemon yatabeanus.

Cryopreservation in liquid nitrogen (LN, -196 °C) is a unique option for the long-term conservation of threatened plant species with non-orthodox or limitedly available seeds. In previous studies, a systematic approach was used to develop a droplet-vitrification (DV) cryopreservation protocol for Postemon yatabeanus shoot tips that includes preculture with 10% sucrose, osmoprotection with C4-35%, cryoprotection with A3-80% vitrification solution, and a three-step regrowth starting with the ammonium-free medium. The tricarboxylic acid (TCA) cycle is a crucial component of plant cell metabolism as it is involved in redox state regulation and energy provision. We hypothesized that organic acids (OAs) associated with the TCA and its side reactions indirectly indicate metabolism intensity and oxidative stress development in shoot tips under the cryopreservation procedure. In this study, the contents of 14 OAs were analyzed using gas chromatography-tandem mass spectrometry (GC-MS/MS) in P. yatabeanus shoot tips in a series of treatments including individual steps of the DV procedure, additional stress imposed by non-optimum protocol conditions (no preculture, no osmoprotection, various vitrification solution composition, using vials instead of aluminum foils, etc.) and regrowth on different media with or without ammonium or growth regulators. The possible relation of OA content with the total cryoprotectant (CPA) concentration and shoot tips regeneration percentage was also explored. Regeneration of cryopreserved shoot tips reduced in descending order as follows: standard protocol condition (91%) > non-optimum vitrification solution (ca. 68%) > non-optimum preculture (60-62%) > regrowth medium (40-64%) > no osmoprotection, cryopreservation in vials (28-30%). Five OAs (glycolic, malic, citric, malonic, and lactic) were the most abundant in the fresh (control) shoot tips. The dynamic pattern of OAs during the DV procedure highly correlated (r = 0.951) with the total CPA concentration employed: it gradually increased through the preculture, osmoprotection, and cryoprotection, peaked at cooling/rewarming (6.38-fold above control level), and returned to the fresh control level after 5 days of regrowth (0.89-fold). The contents of four OAs (2-hydroxybutyric, 3-hydroxypropionic, lactic, and glycolic) showed the most significant (10-209-fold) increase at the cooling/rewarming step. Lactic and glycolic acids were the major OAs at cooling/rewarming, accounting for 81% of the total OAs content. The OAs were categorized into three groups based on their dynamics during the cryopreservation protocol, and these groups were differently affected by protocol step modifications. However, there was no straightforward relationship between the dynamics of OAs and shoot tip regeneration. The results suggest that active modulation of OAs metabolism may help shoot tips to cope with osmotic stress and the chemical cytotoxicity\ of CPAs. Further intensive studies are needed to investigate the effect of cryopreservation on cell primarily metabolism and identify oxidative stress-related biomarkers in plant materials.