An overview of advanced formulation and nanotechnology-based approaches for solubility and bioavailability enhancement of silymarin

Unlocking the Neuroprotective Potential of Silymarin: A Promising Ally in Safeguarding the Brain from Alzheimer's Disease and Other Neurological Disorders

Medicinal plants and their phytochemicals have been extensively employed worldwide for centuries to address a diverse range of ailments, boasting a history that spans several decades. These plants are considered the source of numerous medicinal compounds. For instance, silymarin is a polyphenolic flavonoid extract obtained from the milk thistle plant or Silybum marianum which has been shown to have significant neuroprotective effects and great therapeutic benefits. Neurodegenerative diseases (NDs) are a class of neurological diseases that have become more prevalent in recent years, and although treatment is available, there is no complete cure developed yet. Silymarin utilizes a range of molecular mechanisms, including modulation of MAPK, AMPK, NF-κB, mTOR, and PI3K/Akt pathways, along with various receptors, enzymes, and growth factors. These mechanisms collectively contribute to its protective effects against NDs such as Alzheimer's disease, Parkinson's disease, and depression. Despite its safety and efficacy, silymarin faces challenges related to bioavailability and aqueous solubility, hindering its development as a clinical drug. This review highlights the molecular mechanisms underlying silymarin's neuroprotective effects, suggesting its potential as a promising therapeutic strategy for NDs.

Pharmaceutical technological trends containing flavonoids: a patent review

Flavonoids such as silibinin, hesperetin, and phloretin exhibit well-documented biological activities, including anti-inflammatory, cytoprotective, anticarcinogenic, and antioxidant effects. However, their clinical application remains limited due to challenges such as poor aqueous solubility, low bioavailability, and restricted intestinal absorption, which can significantly reduce their pharmacological efficacy. This review analyzed patents related to innovative pharmaceutical technologies for flavonoids. The analysis used databases from the World Intellectual Property Organization and the European Patent Office. Following a comprehensive screening process, 38 patents were selected for detailed examination. These patents highlighted numerous studies on novel formulations, characterizations, and proprietary conditions. This review highlights technologies, such as nanocapsules, nanoemulsions, solid dispersions, phospholipid carriers, inclusion complexes, microemulsions, and other advanced systems, which enhance bioactive molecules' water solubility and stability. Consequently, these technologies improve permeability and absorption through the intended administration route, demonstrating the potential of flavonoids as promising candidates for various treatments, particularly when integrated into pharmaceutical technologies.

Formulation and Evaluation of a Silymarin Inclusion Complex-Based Gel for Skin Cancer

Silymarin (SLM) is a bioactive, water-insoluble flavonoid reported against different types of cancer. In the present research, the SLM inclusion complex was prepared by the freeze-drying method using different cyclodextrins. The phase solubility study was performed to assess the stability constant and complexation efficiency. The prepared SLM inclusion complexes (F1, F2, and F3) were characterized for different physicochemical and in vitro parameters. Based on the results, the selected inclusion complex (F2) was converted to a topical gel. Finally, it was evaluated for antioxidant, protein denaturation, and cell viability assay (B16F10; skin cancer cell line). The in vitro results were further confirmed by performing a molecular docking study. The phase solubilization results showed the formation of a stable complex with a stability constant value of 548 mol L-1 (βCD-PLX), 911 mol L-1 (HP βCD-PLX), and 736 mol L-1 (M βCD-PLX). A marked increase in release pattern was found from the prepared inclusion complex (80.9 ± 2.2-97.8 ± 3.1%) compared to free SLM (24.1 ± 2.8%). DSC as well as the IR studies confirm the formation of a stable complex. SEM and X-ray diffraction results confirmed the conversion to the amorphous form. The molecular docking studies exhibited the high docking score of SLM with both colchicine-binding sites of the tubulin protein (-6.28 kcal/mol) and complexing agents, viz., βCD (-4.61 kcal/mol), HP βCD (-5.77 kcal/mol), and M βCD (-5.61 kcal/mol). The antioxidant assay results showed that the activity was significantly improved (1.2-1.6 fold) compared to free SLM. The in vitro cell viability assay outcome displayed concentration-dependent activity with a significantly lower IC50 value from F2G2 (145.3 ± 4.2 μg/mL) than free SLM (304.7 ± 5.7 μg/mL). The above conclusions demonstrated that the developed SLM inclusion complex-based gel system could be an ideal delivery system for skin cancer.

A review of the current status of biological effects of plant-derived therapeutics in breast cancer

Phytochemicals are bioactive secondary plant metabolites found in high concentrations in fruits, grains, and vegetables. Recent studies provide evidence of usage of plant-based diets rich in phytochemicals and their corelation to reduction in cancer incidence. Several phytochemicals have demonstrated effectiveness as chemotherapeutic agents against various cancers, including breast cancer. Breast cancer (BC) is a major worldwide medical issue owing to its high incidence, especially in women. It is the most often detected malignancy and an important trigger of mortality in women. Various chemotherapeutics along with radiotherapy are being investigated as potential treatment options for breast cancer. However, multidrug resistance, toxicity to normal cells, and other adverse effects limit the usage of chemotherapeutics in breast cancer. Cancer treatment with dietary phytochemicals is a highly effective approach that is currently gaining widespread attention. This manuscript intends to describe the existing data on the anticancer effects of various phytochemicals, including their preclinical exploration against breast cancer. Phytochemicals are broadly categorized, with an explanation of their role in breast cancer prognosis through various signalling pathways, preclinical status, physicochemical property analysis using Data Warrior, and evidence on individual phototherapeutics.

Staphylococcus aureus major cell division protein FtsZ assembly is inhibited by silibinin, a natural flavonolignan that also blocked bacterial growth and biofilm formation

The bacterial cell division protein FtsZ has been considered a potential therapeutic target due to its rapid treadmilling that induces cellular wall construction in bacteria. The current study discovered a novel antimicrobial compound, silibinin, a natural flavonolignan and its impact on the recombinant S. aureus FtsZ (SaFtsZ). Silibinin inhibited S. aureus Newman growth in a dose-dependent manner. The IC50 and MIC values for silibinin were 75 μM and 200 μM, respectively. It had no cytotoxicity against HEK293 cells in vitro. Silibinin also enlarged the bacterial cell morphology by ∼40 folds and showed antibiofilm property. It perturbed the S. aureus membrane potential both at IC50 conc. and at MIC conc. Further, it inhibited both the polymerization and GTPase activity of SaFtsZ. It did not inhibit tubulin assembly, a eukaryotic FtsZ homolog. A fluorescence quenching study yielded the Kd value for SaFtsZ-Silibinin interaction and binding stoichiometry 0.857 ± 0.188 μM and 1:1, respectively. Both in silico study and competition assay indicated that silibinin binds at the GTP binding site on SaFtsZ. The Ki value for the silibinin-mediated inhibition of SaFtsZ was 8.8 μM. Therefore, these findings have comprehensively shown the antimicrobial behavior of silibinin on S. aureus Newman cells targeting SaFtsZ.

Harnessing machine learning for efficient large-scale interatomic potential for sildenafil and pharmaceuticals containing H, C, N, O, and S

In this study a cutting-edge approach to producing accurate and computationally efficient interatomic potentials using machine learning algorithms is presented. Specifically, the study focuses on the application of Allegro, a novel machine learning algorithm, running on high-performance GPUs for training potentials. The choice of training parameters plays a pivotal role in the quality of the potential functions. To enable this methodology, the "Solvated Protein Fragments" dataset, containing nearly 2.7 million Density Functional Theory (DFT) calculations for many-body intermolecular interactions involving protein fragments and water molecules, encompassing H, C, N, O, and S elements, is considered as the training dataset. The project optimizes computational efficiency by reducing the initial dataset size according to the intended application. To assess the efficacy of the approach, the sildenafil citrate, iso-sildenafil, aspirin, ibuprofen, mebendazole and urea, representing all five relevant elements, serve as the test bed. The results of the Allegro-trained potentials demonstrate outstanding performance, benefiting from the combination of an appropriate training dataset and parameter selection. This notably enhanced computational efficiency when compared to the computationally intensive DFT method aided by GPU acceleration. Validation of the produced interatomic potentials is achieved through Allegro's own evaluation mechanism, yielding exceptional accuracy. Further verification is carried out through LAMMPS molecular dynamics simulations. Structural optimization by energy minimization and NPT Molecular Dynamics simulations are performed for each potential, assessing relaxation processes and energy reduction. Additional structures, including urea, ammonia, uracil, oxalic acid, and acetic acid, are tested, highlighting the potential's versatility in describing systems containing the aforementioned elements. Visualization of the results confirms the scientific accuracy of each structure's relaxation. The findings of this study demonstrate strong scaling and the potential for applications in pharmaceutical research, allowing the exploration of larger molecular structures not previously amenable to computational analysis at this level of accuracy The success of the machine learning approach underscores its potential to revolutionize computational solid-state physics.

Exploring the potential of silymarin-loaded nanovesicles as an effective drug delivery system for cancer therapy: in vivo, in vitro, and in silico experiments

We aimed to perform a comprehensive study on the development and characterization of silymarin (Syl)-loaded niosomes as potential drug delivery systems. The results demonstrate significant novelty and promising outcomes in terms of morphology, size distribution, encapsulation efficiency, in vitro release behavior, free energy profiles of Syl across the niosome bilayer, hydrogen bonding interactions, antimicrobial properties, cytotoxicity, and in vivo evaluations. The physical appearance, size, and morphology assessment of free niosomes and Syl-loaded niosomes indicated stable and well-formed vesicular structures suitable for drug delivery. Transmission electron microscopy (TEM) analysis revealed spherical shapes with distinct sizes for each formulation, confirming uniform distribution. Dynamic light scattering (DLS) analysis confirmed the size distribution results with higher polydispersity index for Syl-loaded niosomes. The encapsulation efficiency of Syl in the niosomes was remarkable at approximately 91%, ensuring protection and controlled release of the drug. In vitro release studies showed a sustained release profile for Syl-loaded niosomes, enhancing therapeutic efficacy over time. Free energy profiles analysis identified energy barriers hindering Syl permeation through the niosome bilayer, emphasizing challenges in drug delivery system design. Hydrogen bonding interactions between Syl and niosome components contributed to energy barriers, impacting drug permeability. Antimicrobial assessments revealed significant differences in inhibitory effects against S. aureus and E. coli. Cytotoxicity evaluations demonstrated the superior tumor-killing potential of Syl-loaded niosomes compared to free Syl. In vivo studies indicated niosome formulations' safety profiles in terms of liver and kidney parameters compared to bulk Syl, showcasing potential for clinical applications. Overall, this research highlights the promising potential of Syl-loaded niosomes as effective drug delivery systems with enhanced stability, controlled release, and improved therapeutic outcomes.

Optimizing Production, Characterization, and In Vitro Behavior of Silymarin-Eudragit Electrosprayed Fiber for Anti-Inflammatory Effects: A Chemical Study

Inflammatory Bowel Disease (IBD) is a chronic condition that affects approximately 1.6 million Americans. While current polyphenols for treating IBD can be expensive and cause unwanted side effects, there is an opportunity regarding a new drug/polymer formulation using silymarin and an electrospray procedure. Silymarin is a naturally occurring polyphenolic flavonoid antioxidant that has shown promising results as a pharmacological agent due to its antioxidant and hepatoprotective characteristics. This study aims to produce a drug-polymer complex named the SILS100-Electrofiber complex, using an electrospray system. The vertical set-up of the electrospray system was optimized at a 1:10 of silymarin and Eudragit® S100 polymer to enhance surface area and microfiber encapsulation. The SILS100-Electrofiber complex was evaluated using drug release kinetics via UV Spectrophotometry, Fourier-Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Differential Scanning Calorimetry (DSC). Drug loading, apparent solubility, and antioxidant activity were also evaluated. The study was successful in creating fiber-like encapsulation of the silymarin drug with strand diameters ranging from 5-7 μm, with results showing greater silymarin release in Simulated Intestinal Fluid (SIF) compared to Simulated Gastric Fluid (SGF). Moving forward, this study aims to provide future insight into the formulation of drug-polymer complexes for IBD treatment and targeted drug release using electrospray and microencapsulation.

Graphene-silymarin-loaded chitosan/gelatin/hyaluronic acid hybrid constructs for advanced full-thickness burn wound management

Burn wounds (BWs) with extensive blood loss, along with bacterial infections and poor healing, may become detrimental and pose significant rehabilitation obstacles in medical facilities. Therefore, the freeze-drying method synthesized novel hemocompatible chitosan, gelatin, and hyaluronic acid infused with graphene oxide-silymarin (CGH-SGO) hybrid constructs for application as a BW patch. Most significantly, synthesized hybrid constructs exhibited an interconnected-porous framework with precise pore sizes (≈118.52 µm) conducive to biological functions. Furthermore, the FTIR and XRD analyses document the constructs' physiochemical interactions. Similarly, enhanced swelling ratios, adequate WVTR (736 ± 78 g m-2 hr-1), and bio-degradation rates were seen during the physiological examination of constructs. Following the in vitro investigations, SMN-GO added to constructs improved their anti-bacterial (against E.coli and S. aureus), anti-oxidant, hemocompatible, and bio-compatible characteristics in conjunction with prolonged drug release. Furthermore, in vivo, implanting constructs on wounds exhibited significant acceleration in full-thickness burn wound (FT-BW) healing on the 14th day (CGH-SGO: 95 ± 2.1 %) in contrast with the control (Gauze: 71 ± 4.2 %). Additionally, contrary to gauze, the in vivo rat tail excision model administered with constructs assured immediate blood clotting. Therefore, CGH-SGO constructs with an improved porous framework, anti-bacterial activity, hemocompatibility, and biocompatibility could represent an attractive option for healing FT-BWs.

Pharmacological Effects of Shikonin and Its Potential in Skin Repair: A Review

Currently, skin injuries have a serious impact on people's lives and socio-economic stress. Shikonin, a naphthoquinone compound derived from the root of the traditional Chinese medicine Shikonin, has favorable biological activities such as anti-inflammatory, antibacterial, immunomodulatory, anticancer, and wound-healing-promoting pharmacological activities. It has been reported that Shikonin can be used for repairing skin diseases due to its wide range of pharmacological effects. Moreover, the antimicrobial activity of Shikonin can play a great role in food and can also reduce the number of pathogenic bacteria in food. This paper summarizes the research on the pharmacological effects of Shikonin in recent years, as well as research on the mechanism of action of Shikonin in the treatment of certain skin diseases, to provide certain theoretical references for the clinical application of Shikonin, and also to provides research ideas for the investigation of the mechanism of action of Shikonin in other skin diseases.

Fisetin-Loaded Nanostructured Lipid Carriers: Formulation and Evaluations against Advanced and Metastatic Melanoma

Fisetin (Fis), a natural flavonoid with anticancer effects, suffers from delivery constraints. Fisetin-nanostructured lipid carriers (NLCs) were developed for better efficacy against metastatic melanoma, employing the design of experiment (DoE) approach. The optimized NLCs depict a particle diameter of 135.0 ± 5.5 nm, a polydispersity index (PDI) of 0.176 ± 0.035, and an entrapment efficiency of 78.16 ± 1.58%. The formulation was stable over a period of 60 days and demonstrated sustained release of the drug (74.79 ± 3.75%) over 96 h. Fis-NLCs depicted at least ∼3.2 times lower IC50 value and ∼1.8 times higher drug uptake at 48 h in A-375 and B16F10 cells compared to that of Fis. It also inhibited the mobility of melanoma cells and induced cell cycle arrest at the G1/S phase. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot results show enhanced expression of Nrf2/NQO1 genes and an apoptotic effect by the upregulation of BAX mRNA expression. The protein levels of BAX and p53 were ∼2-fold higher compared with that of pure Fis. In-vivo studies demonstrated 5.9- and 10.7-fold higher inhibition in melanoma-associated metastasis in the lungs and liver, respectively. The outcomes from this study demonstrated Fis-NLCs as an effective tool against melanoma.

Pharmacological studies of the genus rice (Oryza L.): a literature review

Rice (Oryza L.) is an essential food for more than 50 percent of the world's population and is the world's second-largest grain crop. Pigmented rice comes in various colors, such as black, red, brown, and green. Anthocyanins, like cyanidin-3-O-glucoside and peonidin-3-O-glucoside, are the primary color pigments in colored rice, whereas proanthocyanidins and flavan-3-ol oligosaccharides, with catechins as the central synthesis unit, are found in brown rice. This review article's aim is to give information and a summary of rice activities, research methods, also mechanisms of action (Oryza L.). Intake of pigmented rice was already associated with a number of health benefits, including antioxidant activity, anticancer, antitumor, antidiabetic activity, and a reduced risk of cardiovascular disease. Rice contains several bioactive compounds, such as γ-oryzanol, phenolic acid, anthocyanins, proanthocyanidins, flavonoids, carotenoids, and phytosterols, which have been widely studied and shown to have several pharmacological activities. The use of current herbal compounds is rapidly increasing, including the practice of pharmacological disease prevention and treatment. Herbal remedies have entered the international market as a result of research into plant biopharmaceuticals and nutraceuticals. Through a variety of pharmacological activities, it is clear that Oryza L. is a popular herb. As a result, additional research on Oryza L. can be conducted to investigate more recent and comprehensive pharmacological effectiveness, to provide information and an overview of Rice (Oryza L.) activities, research methods, and mechanisms of action. Several natural substances are characterized by low water solubility, low stability, and sensitivity to light and oxygen, and the potential for poor absorption of the active substances requires modification of the formulation. To improve the effectiveness of pharmacologically active substances originating from natural ingredients, drug delivery systems that use lipid-based formulations can be considered innovations.

Pharmaceutical prospects of Silymarin for the treatment of neurological patients: an updated insight

Background

Silymarin is a polyphenolic flavonoid complex extricated from dried fruits and seeds of the plant Silybum marianum L. Chemically, it is a mixture of flavonolignan complexes consisting of silybin, isosilybin, silychristin, silydianin, a minor quantity of taxifolin, and other polyphenolic compounds, which possess different bio medicinal values.

Purpose

This review critically looks into the current status, pharmaceutical prospects and limitations of the clinical application of Silymarin for treating neurological disorders. In particular, Silymarin's medicinal properties and molecular mechanisms are focused on providing a better-compiled understanding helpful in its neuro-pharmacological or therapeutic aspects.

Methods

This review was compiled by the literature search done using three databases, i.e., PubMed (Medline), EMBASE and Science Direct, up to January 2023, using the keywords-Silymarin, neurological disorders, cognitive disorders, Type 2 Diabetes, pharmaceutical prospects and treatment. Then, potentially relevant publications and studies (matching the eligible criteria) were retrieved and selected to explain in this review using PRISMA 2020 (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) study flow chart.

Result

Since its discovery, it has been widely studied as a hepatoprotective drug for various liver disorders. However, in the last 10-15 years, several research studies have shown its putative neuroprotective nature against various brain disorders, including psychiatric, neurodegenerative, cognitive, metabolic and other neurological disorders. The main underlying neuroprotective mechanisms in preventing and curing such disorders are the antioxidant, anti-inflammatory, anti-apoptotic, pro-neurotrophic and pro-estrogenic nature of the bioactive molecules.

Conclusion

This review provides a lucid summary of the well-studied neuroprotective effects of Silymarin, its underlying molecular mechanisms and current limitations for its usage during neurological disorders. Finally, we have suggested a future course of action for developing it as a novel herbal drug for the treatment of brain diseases.

Preparation, Characterization and Evaluation of Flavonolignan Silymarin Effervescent Floating Matrix Tablets for Enhanced Oral Bioavailability

The convenient and highly compliant route for the delivery of active pharmaceutical ingredients is the tablet. A versatile platform of tablets is available for the delivery of therapeutic agents to the gastrointestinal tract. This study aimed to prepare gastro retentive drug delivery floating tablets of silymarin to improve its oral bioavailability and solubility. Hydroxypropyl methylcellulose (HPMCK4M and HPMCK15), Carbopol 934p and sodium bicarbonate were used as a matrix, floating enhancer and gas generating agent, respectively. The prepared tablets were evaluated for physicochemical parameters such as hardness, weight variation, friability, floating properties (floating lag time, total floating time), drug content, stability study, in vitro drug release, in vivo floating behavior and in vivo pharmacokinetics. The drug–polymer interaction was studied by Differential Scanning Calorimetry (DSC) thermal analysis and Fourier transform infrared (FTIR). The floating lag time of the formulation was within the prescribed limit (<2 min). The formulation showed good matrix integrity and retarded the release of drug for >12 h. The dissolution can be described by zero-order kinetics (r2 = 0.979), with anomalous diffusion as the release mechanism (n = 0.65). An in vivo pharmacokinetic study showed that Cmax and AUC were increased by up to two times in comparison with the conventional dosage form. An in vivo imaging study showed that the tablet was present in the stomach for 12 h. It can be concluded from this study that the combined matrix system containing hydrophobic and hydrophilic polymers min imized the burst release of the drug from the tablet and achieved a drug release by zero-order kinetics, which is practically difficult with only a hydrophilic matrix. An in vivo pharmacokinetic study elaborated that the bioavailability and solubility of silymarin were improved with an increased mean residence time.

Comparative efficacy of silibinin and nano-silibinin on lead poisoning in Male Wistar rats

Lead (Pb) is an environmental neurotoxin that can lead to toxicity. It has shown that tissues can be exposed to oxidative stress in lead poisoning. Since silymarin is a natural agent with antioxidant effects, this study aimed to investigate the antioxidant and chelation effects of silibinin and nano-silibinin on the oxidative stress status in lead-poisoned rats. Sixty male Wistar rats randomly divided into ten groups (n = 6). Control and Pb groups treated with or without silibinin and nano-silibinin for six days. Following measuring of weight and blood lead levels, biochemical antioxidant parameters evaluated. Finally, a histopathological examination of the liver performed. In this experiment, silibinin and more efficiently nano-silibinin prevented weight loss and blood lead level elevation induced by lead. Also, they increased the attenuated levels of superoxide dismutase (SOD) activity, catalase (CAT), total thiol molecules (TTM), glutathione (GSH), and total antioxidant capacity (TAC). Lead-induced elevation of lipid peroxidation products (MDA) and nitric oxide (NO) normalized to the standard level in silibinin and especially nano-silibinin groups. These data suggested that silibinin and especially nano-silibinin can decrease blood lead levels and prevent weight loss and oxidative stress in the lead-poisoned rat's model.

A review of nanostructured delivery systems for the encapsulation, protection, and delivery of silymarin: An emerging nutraceutical

Silymarin exhibits biological activities that may promote human health and wellbeing, including antioxidant, antimicrobial, anti-inflammatory, and anti-cancer activities. Consequently, it has potential for application as a nutraceutical ingredient in functional foods and supplements. But its application for this purpose is currently limited by its poor water solubility, chemical stability, and bioavailability. The potential of nano-delivery systems to improve the functional performance of silymarin was reviewed in this manuscript. The formation, attributes, and applications of biopolymer-based, lipid-based, surfactant-based, and miscellaneous nanocarriers are discussed. In particular, the impact of the different delivery systems such as biopolymer-based, lipid-based delivery systems on the gastrointestinal fate of silymarin is summarized. The encapsulation in edible nanocarriers can improve the bioavailability of silymarin by enhancing its water-dispersibility, inhibiting its degradation, and increasing its absorption.These nanocarriers may therefore be utilized to incorporate this nutraceutical into functional foods and supplements in a bioavailable form.

Flavonoids and intestinal microbes interact to alleviate depression

Flavonoids have a variety of biological activities that are beneficial to human health. However, owing to low bioavailability, most flavonoids exert beneficial effects in the intestine through metabolism by the flora into a variety of structurally different derivatives. Also, flavonoids can modulate the type and structure of intestinal microorganisms to improve human health. It has been reported that the development of depression is accompanied by changes in the type and number of intestinal microorganisms, and gut microbes can significantly improve depressive symptoms through the gut-brain axis. Therefore, the interaction between flavonoids and intestinal microbes to alleviate depression is discussed. © 2021 Society of Chemical Industry.

In vitro Dissolution Testing and Pharmacokinetic Studies of Silymarin Solid Dispersion After Oral Administration to Healthy Pigs

We evaluated the pharmacokinetics of silymarin solid dispersion in pigs to determine whether silybin bioavailability would be increased over that of a silymarin premix. In vitro dissolution testing was conducted using dissolution apparatus 1 (baskets) at 100 rpm at 37 ± 0.5°C in pH 1.2 HCl, pH 6.8 phosphate, and pH 4.3 acetate buffers containing 0.5% Tween-80. In vivo pharmacokinetics were studied using 16 healthy pigs (Yorkshire × Landrace) that were randomly assigned to two groups. Silymarin as solid dispersion and premix dosage forms were administered directly by stomach tubes at 50 mg kg⁻¹ silybin. In vitro dissolution of silybin for the premix was 35.02, 35.90, and 38.70% in these buffers, respectively. In contrast, silybin dissolution in solid dispersions was increased to 82.92, 87.48, and 99.70%, respectively. Silymarin solid dispersion administered at a single dose resulted in a peak concentration (C_max) of 1,190.02 ± 246.97 ng ml⁻¹ with the area under the curve (AUC_0−∞) at 1,299.19 ± 67.61 ng ml⁻¹ h. These parameters for the premix groups were 411.35 ± 84.92 ng ml⁻¹ and 586.82 ± 180.99 ng ml⁻¹ h, respectively. The C_max and AUC_0−∞ values for the solid dispersion were about twice that of the premix and were consistent with the in vitro dissolution data.

Biological Activities, Pharmacokinetics and Toxicity of Nootkatone: A Review

Abstract:

Plant-based drugs have a significant impact on modern therapeutics due to their vast array of pharmacological activities. The integration of herbal plants in the current healthcare system has emerged as a new field of research. It can be used for the identification of novel lead compound candidates for future drug development. Nootkatone is a sesquiterpene derivative and an isolate of grapefruit. Shreds of evidence illustrate that nootkatone targets few molecular mechanisms to exhibit its pharmacological activity and yet needs more exploration to be established. The current review is related to nootkatone, drafted through a literature search using research articles and books from different sources, including Science Direct, Google Scholar, Elsevier, PubMed, and Scopus. It has been reported to possess a wide range of pharmacological activities such as anti-inflammatory, anticancer, antibacterial, hepatoprotective, neuroprotective, and cardioprotective. Although preclinical studies in experimental animal models suggest that nootkatone has therapeutic potential, it is further warranted to evaluate its toxicity and pharmacokinetic parameters before being applied to humans. Hence in the present review, we have summarized the scientific knowledge on nootkatone with a particular emphasis on its pharmacological properties to encourage researchers for further exploration in preclinical and clinical settings.

Cold-Active Lipase-Based Biocatalysts for Silymarin Valorization through Biocatalytic Acylation of Silybin

Extremophilic biocatalysts represent an enhanced solution in various industrial applications. Integrating enzymes with high catalytic potential at low temperatures into production schemes such as cold-pressed silymarin processing not only brings value to the silymarin recovery from biomass residues, but also improves its solubility properties for biocatalytic modification. Therefore, a cold-active lipase-mediated biocatalytic system has been developed for silybin acylation with methyl fatty acid esters based on the extracellular protein fractions produced by the psychrophilic bacterial strain Psychrobacter SC65A.3 isolated from Scarisoara Ice Cave (Romania). The extracellular production of the lipase fraction was enhanced by 1% olive-oil-enriched culture media. Through multiple immobilization approaches of the cold-active putative lipases (using carbodiimide, aldehyde-hydrazine, or glutaraldehyde coupling), bio-composites (S1–5) with similar or even higher catalytic activity under cold-active conditions (25 °C) have been synthesized by covalent attachment to nano-/micro-sized magnetic or polymeric resin beads. Characterization methods (e.g., FTIR DRIFT, SEM, enzyme activity) strengthen the biocatalysts’ settlement and potential. Thus, the developed immobilized biocatalysts exhibited between 80 and 128% recovery of the catalytic activity for protein loading in the range 90–99% and this led to an immobilization yield up to 89%. The biocatalytic acylation performance reached a maximum of 67% silybin conversion with methyl decanoate acylating agent and nano-support immobilized lipase biocatalyst.

New Perspectives in Drug Delivery Systems for the Treatment of Tuberculosis

BACKGROUND

Tuberculosis is a chronic respiratory disease caused by Mycobacterium tuberculosis. The common treatment regimens of tuberculosis are lengthy with adverse side effects, low patient compliance, and antimicrobial resistance. Drug delivery systems (DDSs) can overcome these limitations.

OBJECTIVE

This review aims to summarize the latest DDSs for the treatment of tuberculosis. In the first section, the main pharmacokinetic and pharmacodynamic challenges, due to the innate properties of the drugs, are put forth. The second section elaborates on the use of DDS to overcome the disadvantages of the current treatment of tuberculosis.

CONCLUSION

We reviewed research articles published in the last 10 years. DDSs can improve the physicochemical properties of anti-tuberculosis drugs, improving solubility, stability, and bioavailability, with better control of drug release and can target alveolar macrophages. However, more preclinical studies and robust bio-relevant analyses are needed for DDSs to become a feasible option to treat patients and attract investors.