Factorial design for preparing chitosan nanoparticles and its use for loading and controlled release of indole-3-acetic acid with effect on hydroponic lettuce crops

Oral Delivery of Liraglutide-Loaded Zein/Eudragit-Chitosan Nanoparticles Provides Pharmacokinetic and Glycemic Outcomes Comparable to Its Subcutaneous Injection in Rats

Liraglutide (LIRA) is a glucagon-like peptide-1 (GLP-1) receptor agonist renowned for its efficacy in treating type 2 diabetes mellitus (T2DM) and is typically administered via subcutaneous injections. Oral delivery, although more desirable for being painless and potentially enhancing patient adherence, is challenged by the peptide's low bioavailability and vulnerability to digestive enzymes. This study aimed to develop LIRA-containing zein-based nanoparticles stabilized with eudragit RS100 and chitosan for oral use (Z-ERS-CS/LIRA). These nanoparticles demonstrated a spherical shape, with a mean diameter of 238.6 nm, a polydispersity index of 0.099, a zeta potential of +40.9 mV, and an encapsulation efficiency of 41%. In vitro release studies indicated a prolonged release, with up to 61% of LIRA released over 24 h. Notably, the nanoparticles showed considerable resistance and stability in simulated gastric and intestinal fluids, suggesting protection from pH and enzymatic degradation. Pharmacokinetic analysis revealed that orally administered Z-ERS-CS/LIRA paralleled the pharmacokinetic profile seen with subcutaneously delivered LIRA. Furthermore, in vivo tests on a diabetic rat model showed that Z-ERS-CS/LIRA significantly controlled glucose levels, comparable to the results observed with free LIRA. The findings underscore Z-ERS-CS/LIRA nanoparticles as a promising approach for oral LIRA delivery in T2DM management.

Advances in nanoparticle and organic formulations for prolonged controlled release of auxins

Plant hormones have been well known since Charles Darwin as signaling molecules directing plant metabolism. Their action and transport pathways are at the top of scientific interest and were reviewed in many research articles. Modern agriculture applies phytohormones as supplements to achieve desired physiological plant response. Auxins are a class of plant hormones extensively used for crop management. Auxins stimulate the formation of lateral roots and shoots, seed germination, while extensively high concentrations of these chemicals act as herbicides. Natural auxins are unstable; light or enzyme action leads to their degradation. Moreover, the concentration dependant action of phytohormones denier one-shot injection of these chemicals and require constant slow additive of supplement. It obstructs the direct introduction of auxins. On the other hand, delivery systems can protect phytohormones from degradation and provide a slow release of loaded drugs. Moreover, this release can be managed by external stimuli like pH, enzymes, or temperature. The present review is focused on three auxins: indole-3-acetic, indole-3-butyric, and 1-naphthaleneacetic acids. We collected some examples of inorganic (oxides, Ag, layered double hydroxides) and organic (chitosan, organic formulations) delivery systems. The action of carriers can enhance auxin effects via protection and targeted delivery of loaded molecules. Moreover, nanoparticles can act as nano fertilizers, intensifying the phytohormone effect, providing slow controlled release. So delivery systems for auxins are extremely attractive for modern agriculture opening sustainable management of plant metabolism and morphogenesis.

Encapsulated plant growth regulators and associative microorganisms: Nature-based solutions to mitigate the effects of climate change on plants

Over the past decades, the atmospheric CO₂ concentration and global average temperature have been increasing, and this trend is projected to soon become more severe. This scenario of climate change intensifies abiotic stress factors (such as drought, flooding, salinity, and ultraviolet radiation) that threaten forest and associated ecosystems as well as crop production. These factors can negatively affect plant growth and development with a consequent reduction in plant biomass accumulation and yield, in addition to increasing plant susceptibility to biotic stresses. Recently, biostimulants have become a hotspot as an effective and sustainable alternative to alleviate the negative effects of stresses on plants. However, the majority of biostimulants have poor stability under environmental conditions, which leads to premature degradation, shortening their biological activity. To solve these bottlenecks, micro- and nano-based formulations containing biostimulant molecules and/or microorganisms are gaining attention, as they demonstrate several advantages over their conventional formulations. In this review, we focus on the encapsulation of plant growth regulators and plant associative microorganisms as a strategy to boost their application for plant protection against abiotic stresses. We also address the potential limitations and challenges faced for the implementation of this technology, as well as possibilities regarding future research.

Application of Data Modeling, Instrument Engineering and Nanomaterials in Selected Medid the Scientific Recinal Plant Tissue Culture

At present, most precious compounds are still obtained by plant cultivation such as ginsenosides, glycyrrhizic acid, and paclitaxel, which cannot be easily obtained by artificial synthesis. Plant tissue culture technology is the most commonly used biotechnology tool, which can be used for a variety of studies such as the production of natural compounds, functional gene research, plant micropropagation, plant breeding, and crop improvement. Tissue culture material is a basic and important part of this issue. The formation of different plant tissues and natural products is affected by growth conditions and endogenous substances. The accumulation of secondary metabolites are affected by plant tissue type, culture method, and environmental stress. Multi-domain technologies are developing rapidly, and they have made outstanding contributions to the application of plant tissue culture. The modes of action have their own characteristics, covering the whole process of plant tissue from the induction, culture, and production of natural secondary metabolites. This paper reviews the induction mechanism of different plant tissues and the application of multi-domain technologies such as artificial intelligence, biosensors, bioreactors, multi-omics monitoring, and nanomaterials in plant tissue culture and the production of secondary metabolites. This will help to improve the tissue culture technology of medicinal plants and increase the availability and the yield of natural metabolites.

Synthesis of Chitosan Microparticles Encapsulating Bacterial Cell-Free Supernatants and Indole Acetic Acid, and Their Effects on Germination and Seedling Growth in Tomato (Solanum lycopersicum)

Encapsulation of biostimulant metabolites has gained popularity as it increases their shelf life and improves their absorption, being considered a good alternative for the manufacture of products that stimulate plant growth and fruit production. Cell-free supernatants (CFS) were obtained from nine indole-3-acetic acid (IAA) producing bacterial strains. Stenotrophomonas maltophilia (PT53T) produced the highest concentration of IAA (15.88 μg/mL) after 48 h of incubation. CFS from this strain, as well as an IAA standard were separately encapsulated in chitosan microparticles (CS-MP) using the ionic gelation method. The CS-MP were analyzed by Fourier transform infrared spectroscopy (FTIR), showing absorption bands at 1641, 1547, and 1218 cm-1, associated with the vibrations of the carbonyl C=O, the N-H amine, and the bond between chitosan (CHI) and sodium tripolyphosphate (TPP). The effects of unencapsulated CFS, encapsulated CFS (EN-CFS), and encapsulated IAA standard (EN-IAA) on germination and growth of seven-day-old tomato (Solanum lycopersicum) seedlings were studied. Results showed that both EN-CFS and EN-IAA significantly (p < 0.05) increased seed germination rates by 77.5 and 80.8%, respectively. Both CFS and EN-IAA produced the greatest increase in aerial part length and fresh weight with respect to the treatment-free test. Therefore, it was concluded that the application of EN-CFS or EN-IAA could be a good option to improve the germination and growth of tomato seedlings.

Hyaluronic acid-coated chitosan nanoparticles as carrier for the enzyme/prodrug complex based on horseradish peroxidase/indole-3-acetic acid: Characterization and potential therapeutic for bladder cancer cells

Hybrid nanoparticles composed of different biopolymers for delivery of enzyme/prodrug systems are of interest for cancer therapy. Hyaluronic acid-coated chitosan nanoparticles (CS/HA NP) were prepared to encapsulate individually an enzyme/pro-drug complex based on horseradish peroxidase (HRP) and indole-3-acetic acid (IAA). CS/HA NP showed size around 158 nm and increase to 170 and 200 nm after IAA and HRP encapsulation, respectively. Nanoparticles showed positive zeta potential values (between +20.36 mV and +24.40 mV) and higher encapsulation efficiencies for both nanoparticles (up to 90 %) were obtained. Electron microscopy indicated the formation of spherical particles with smooth surface characteristic. Physicochemical and thermal characterizations suggest the encapsulation of HRP and IAA. Kinetic parameters for encapsulated HRP were similar to those of the free enzyme. IAA-CS/HA NP showed a bimodal release profile of IAA with a high initial release (72 %) followed by a slow-release pattern. The combination of HRP-CS/HA NP and IAA- CS/HA NP reduced by 88 % the cell viability of human bladder carcinoma cell line (T24) in the concentrations 0.5 mM of pro-drug and 1.2 μg/mL of the enzyme after 24 h.

A pH-sensitive nanocarrier based on BSA-stabilized graphene-chitosan nanocomposite for sustained and prolonged release of anticancer agents

Smart nanomaterials with stimuli-responsive behavior are considered as promising platform for various drug delivery applications. Regarding their specific conditions, such as acidic pH, drug carriers to treatment of tumor microenvironment need some criteria to enhance drug delivery efficiency. In this study, for the first time, pH-sensitive BSA-stabilized graphene (BSG)/chitosan nanocomposites were synthesized through electrostatic interactions between the positively charged chitosan nanoparticles and negatively charged BSG and used for Doxorubicin (DOX) encapsulation as a general anticancer drug. Physicochemical characterization of the nanocomposites with different concentrations of BSG (0.5, 2, and 5wt%) showed effective decoration of chitosan nanoparticles on BSG. Comparing DOX release behavior from the nanocomposites and free BSG-chitosan nanoparticles were evaluated at two pHs of 7.4 and 4.5 in 28 days. It was shown that the presence of BSG significantly reduced the burst release observed in chitosan nanoparticles. The nanocomposite of 2wt% BSG was selected as the optimal nanocomposite with a release of 84% in 28 days and with the most uniform release in 24 h. Furthermore, the fitting of release data with four models including zero-order, first-order, Higuchi, and Korsmeyer-Peppas indicated that the addition of BSG changed the release mechanism of the drug, enabling uniform release for the optimal nanocomposite in first 24 h, compared to that for pure chitosan nanoparticles. This behavior was proved using metabolic activity assay of the SKBR-3 breast cancer cell spheroids exposed to DOX release supernatant at different time intervals. It was also demonstrated that DOX released from the nanocomposite had a significant effect on the suppression of cancer cell proliferation at acidic pH.

Sustainable Agriculture Systems in Vegetable Production Using Chitin and Chitosan as Plant Biostimulants

Chitin and chitosan are natural compounds that are biodegradable and nontoxic and have gained noticeable attention due to their effective contribution to increased yield and agro-environmental sustainability. Several effects have been reported for chitosan application in plants. Particularly, it can be used in plant defense systems against biological and environmental stress conditions and as a plant growth promoter—it can increase stomatal conductance and reduce transpiration or be applied as a coating material in seeds. Moreover, it can be effective in promoting chitinolytic microorganisms and prolonging storage life through post-harvest treatments, or benefit nutrient delivery to plants since it may prevent leaching and improve slow release of nutrients in fertilizers. Finally, it can remediate polluted soils through the removal of cationic and anionic heavy metals and the improvement of soil properties. On the other hand, chitin also has many beneficial effects such as plant growth promotion, improved plant nutrition and ability to modulate and improve plants’ resistance to abiotic and biotic stressors. The present review presents a literature overview regarding the effects of chitin, chitosan and derivatives on horticultural crops, highlighting their important role in modern sustainable crop production; the main limitations as well as the future prospects of applications of this particular biostimulant category are also presented.

Chitosan and chitosan/PEG nanoparticles loaded with indole-3-carbinol: Characterization, computational study and potential effect on human bladder cancer cells

Indole-3-carbinol (I3C) is a plant molecule known to be active against several types of cancer, but some chemical characteristics limit its clinical applications. In order to overcome these limitations, polymeric nanoparticles can be used as carrier systems for targeted delivery of I3C. In this study, chitosan and chitosan/polyethylene glycol nanoparticles (CS NP and CS/PEG NP, respectively) were prepared to encapsulate I3C by ionic gelation method. The polymeric nanoparticles were characterized by Dynamic Scattering Light (DLS), Zeta Potential (ZP), Fourier Transform Infrared (FTIR) spetroscopy, X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and Field Emission Gun Scanning Electron Microscopy (FEG-SEM). I3C release testing was performed at an acidic media and the interactions between I3C and chitosan or PEG were evaluated by Density Functional Theory (DFT). Cytotoxicity of nanoparticles in bladder cancer T24 cell line was evaluated by the Methyl-thiazolyl-tetrazolium (MTT) colorimetric assay. The average size of the nanoparticles was observed to be in the range from 133.3 ± 3.7 nm to 180.4 ± 2.7 nm with a relatively homogeneous distribution. Samples had relatively high positive zeta potential values (between +20.3 ± 0.5 mV and + 24.3 ± 0.5 mV). Similar encapsulation efficiencies (about 80%) for both nanoparticles were obtained. Physicochemical and thermal characterizations pointed to the encapsulation of I3c. electron microscopy showed spherical particles with smooth or ragged surface characteristics, depending on the presence of PEG. The mathematical fitting of the release profile demonstrated that I3C-CS NP followed the Higuchi model whereas I3C-CS/PEG NP the Korsmeyer-Peppas model. Chemical differences between the nanoparticles as based on the I3C/CS or I3C/PEG interactions were demonstrate by computational characterization. The assessment of cell viability by the MTT test showed that the presence of both free I3C and I3C-loaded nanoparticles lead to statistically significant reduction in T24 cells viability in the concentrations from 500 to 2000 μM, when comparison to the control group after 24 h of exposure. Thus, CS and CS/PEG nanoparticles present as feasible I3C carrier systems for cancer therapy.