Potential use of bixin beyond function as a natural colourant in food and cosmetics.

Bixin is a carotenoid found in the covering of Bixa orellana seeds and widely used as a dye, mainly in food products and cosmetics. This compound is insoluble in water, but technologies have been developed for its use in aqueous preparations, as well as a component for new formulations to disperse other lipophilic ingredients. It has recently aroused the interest of researchers in areas such as Pharmacology, Endocrinology and Oncology, but also new applications in Food Technology. This work aimed to review the main studies in the period from 1911 to 2023, but we emphasised aspects in technologies related to the field of health such as Pharmacology and Pharmacy. We used 'bixin' as a keyword to search for articles on the Web of Science and obtained 488 results, most of which were original articles and 20 were reviews. The analysis demonstrated a continuing large number of studies in Food Technology, but a rapid growth in areas related to health aspects.

Nephrotoxicity in Rats Exposed to Paracetamol: The Protective Role of Moralbosteroid, a Steroidal Glycoside.

Paracetamol (PCM) has an acceptable safety profile when used at prescribed doses. However, it is now understood that paracetamol can damage the kidneys when administered as an overdose. In addition, oxidative stress can play a major role in causing nephrotoxicity. This investigation studies the efficacy of moralbosteroid isolated from M. alba stem bark. Nephrotoxicity was induced with administration of paracetamol. Nephroprotection was studied using two doses of the extract. The experimental animals were divided into four groups (n = 6). Two groups served as positive and negative controls, respectively, and two received the test substances. All of the contents were orally administered. Significant reductions in nephrotoxicity and oxidative damages were observed in the treatment groups. There was a marked decrease in blood levels of urea, creatinine, and lipid peroxidation. Furthermore, it was found that glutathione levels in the blood increased dramatically after treatment. Histological findings confirmed the potent renoprotective potential of moralbosteroid. This was evidenced by the minimized intensity of nephritic cellular destruction. In animal studies, moralbosteroid exhibited dose-dependent activity, which is thought to be mediated through its antioxidant potential.

Dual crosslinked pectin-alginate network as sustained release hydrophilic matrix for repaglinide.

Repaglinide, an oral antidiabetic agent, has a rapid onset of action and short half-life of approximately 1h. Developing a controlled and prolonged release delivery system is required to maintain its therapeutic plasma concentration and to eliminate its adverse effects particularly hypoglycemia. The present study aimed to develop controlled release repaglinide loaded beads using sodium alginate and pectin with dual cross-linking for effective control of drug release. The prepared beads were characterized for size, percentage drug entrapment efficiency, in vitro drug release and the morphological examination using scanning electron microscope. For the comparative study, the release profile of a marketed conventional tablet of repaglinide (Prandin® tablets 2mg, Novo Nordisk) was determined by the same procedure as followed for beads. The particle size of beads was in the range of 698±2.34-769±1.43µm. The drug entrapment efficiency varied between 55.24±4.61 to 82.29±3.42%. The FTIR results suggest that there was no interaction between repaglinide and excipients. The XRD and DSC results suggest partial molecular dispersion and amorphization of the drug throughout the system. These results suggest that repaglinide did not dissolve completely in the polymer composition and seems not to be involved in the cross-linking reaction. The percent drug release was decreased with higher polymer concentrations. In conclusion, the developed beads could enhance drug entrapment efficiency, prolong the drug release and enhance bioavailability for better control of diabetes.

Hydrogel Based Drug Delivery Systems: A Review with Special Emphasis on Challenges Associated with Decontamination of Hydrogels and Biomaterials.

BACKGROUND: Many researches involving the development of new techniques and biomaterials to formulate a suitable drug delivery system and tissue engineering have been conducted. The majority of published literature from these researches emphasizes the production and materials characterization. The safety aspect of hydrogels and biomaterials is a major constraint in their biological applications. OBJECTIVE: The present review article aimed to summarize various literatures that encompass the difficulties encountered with decontamination and sterilization methods in the preparations of biomaterials and especially hydrogels for biological applications. METHOD: We searched for original and review articles from various indexed journals reporting applications of hydrogels and biomaterials in drug delivery systems and the importance of decontamination process for hydrogel containing preparations based on various patents evidences. RESULTS: Despite the vast literature available, limited information regarding the decontamination and sterilization processes related to hydrogels and biomaterials is reported. Sterilization processes to hydrogels are not yet fully explored. Researchers working on hydrogel based systems can consider decontamination of such biomaterial as an important tool to allow for commercialization within the chemical, herbal or pharmaceutical industries. CONCLUSION: Unfortunately, till date, limited papers are available which reported the challenges associated with decontamination methods to prepare hydrogels and biomaterials for biological applications. In conclusion, each case of biomaterial requires individual consideration to decontamination and/or sterilization. This must be submitted to a specific method, but more than one technique can be involved. Physicochemical and biological alterations must be avoided and evaluated by the appropriate assays method. Furthermore, it is also important to consider that each method must be validated depending upon the process variables.

Preparation and characterization of metoprolol tartrate containing matrix type transdermal drug delivery system.

The present study aimed to develop matrix-type transdermal drug delivery system (TDDS) of metoprolol tartrate using polyvinyl pyrrolidone (PVP) and polyvinyl alcohol (PVA). The transdermal films were evaluated for physical parameters, Fourier transform infrared spectroscopy analysis (FTIR), differential scanning calorimetry (DSC), in vitro drug release, in vitro skin permeability, skin irritation test and stability studies. The films were found to be tough, non-sticky, easily moldable and possess good tensile strength. As the concentration of PVA was increased, the tensile strength of the films was also increased. Results of FTIR spectroscopy and DSC revealed the absence of any drug-polymer interactions. In vitro release of metoprolol followed zero-order kinetics and the mechanism of release was found to be diffusion rate controlled. In vitro release studies of metoprolol using Keshary-Chein (vertical diffusion cell) indicated 65.5 % drug was released in 24 h. In vitro skin permeation of metoprolol transdermal films showed 58.13 % of the drug was released after 24 h. In vitro skin permeation of metoprolol followed zero-order kinetics in selected formulations. The mechanism of release was found to be diffusion rate controlled. In a 22-day skin irritation test, tested formulation of transdermal films did not exhibit any allergic reactions, inflammation, or contact dermatitis. The transdermal films showed good stability in the 180-day stability study. It can be concluded that the TDDS of MPT can help in bypassing the first-pass effect and will provide patient improved compliance, without sacrificing the therapeutic advantages of the drugs.

About the Sterilization of Chitosan Hydrogel Nanoparticles.

In the last years, nanostructured biomaterials have raised a great interest as platforms for delivery of drugs, genes, imaging agents and for tissue engineering applications. In particular, hydrogel nanoparticles (HNP) associate the distinctive features of hydrogels (high water uptake capacity, biocompatibility) with the advantages of being possible to tailor its physicochemical properties at nano-scale to increase solubility, immunocompatibility and cellular uptake. In order to be safe, HNP for biomedical applications, such as injectable or ophthalmic formulations, must be sterile. Literature is very scarce with respect to sterilization effects on nanostructured systems, and even more in what concerns HNP. This work aims to evaluate the effect and effectiveness of different sterilization methods on chitosan (CS) hydrogel nanoparticles. In addition to conventional methods (steam autoclave and gamma irradiation), a recent ozone-based method of sterilization was also tested. A model chitosan-tripolyphosphate (TPP) hydrogel nanoparticles (CS-HNP), with a broad spectrum of possible applications was produced and sterilized in the absence and in the presence of protective sugars (glucose and mannitol). Properties like size, zeta potential, absorbance, morphology, chemical structure and cytotoxicity were evaluated. It was found that the CS-HNP degrade by autoclaving and that sugars have no protective effect. Concerning gamma irradiation, the formation of agglomerates was observed, compromising the suspension stability. However, the nanoparticles resistance increases considerably in the presence of the sugars. Ozone sterilization did not lead to significant physical adverse effects, however, slight toxicity signs were observed, contrarily to gamma irradiation where no detectable changes on cells were found. Ozonation in the presence of sugars avoided cytotoxicity. Nevertheless, some chemical alterations were observed in the nanoparticles.

The Microbial Quality Aspects and Decontamination Approaches for the Herbal Medicinal Plants and Products: An in-Depth Review.

BACKGROUND: The present review article provides an overview of the published literature concerning microbial quality of medicinal plants and products and their decontamination methods. It is important to analyze different aspects regarding the cultivation, growing, harvesting, storage, manufacturing, and decontamination of medicinal plant products. Herbal medicinal plants bear a massive microbial load leading to contamination and mycotoxin, which needs to be considered, and properly controlled using suitable sterilization and decontamination methods. METHODS: The main focus of this review is on the definition, advantages, disadvantages and applications of decontamination methods, particularly to show that one must consider the characteristics of the initial sample to be decontaminated. RESULTS: The effects of various methods (ozone, plasma, irradiation) on medicinal herbs and products treated for microbiological decontamination are dependent on factors related to microbial load (i.e., nature and amount of initial contamination), herb/product matrix (i.e., complexity of chemical composition, physical state - solid or liquid) and treatment conditions (i.e., time, irradiation dose, absence or presence of oxygen). In addition, it is important to accept some loss of the chemical compounds, while decreasing microbial load to acceptable limits according to official herbal pharmacopoeias and literature, thus ensuring a final product with quality, safety and therapeutic efficacy. CONCLUSION: The conclusion, which comes from this contribution, is that herbal medicine has more contaminants than a chemically welldefined drug, thus, good manufacturing practices should be followed.

Norfloxacin and metronidazole topical formulations for effective treatment of bacterial infections and burn wounds.

INTRODUCTION: Our various previous findings have shown the suitability of norfloxacin in the treatment of bacterial infections and burn wounds in alone as well as in combination with Curcuma longa in various topical (ointments, gels, and creams) and transdermal drug delivery systems. AIMS AND METHODS: Keeping these facts in consideration, we have made an another attempt to prepare semisolid formulations containing 1% w/w of norfloxacin and metronidazole with different bases like Carbopol, polyethylene glycol, and hydroxypropylmethyl cellulose for effective treatment of bacterial infections and burn wounds. The prepared formulations were evaluated for physicochemical parameters, in vitro drug release, antimicrobial activity, and burn wound healing properties. RESULTS: The prepared formulations were compared with Silver Sulfadiazine cream 1%, USP. Antimicrobial activity of norfloxacin semisolid formulations was found to be equally effective against both aerobic and anaerobic bacteria in comparison to a marketed formulation of Silver Sulfadiazine 1% cream, USP. Based on the burn wound healing property, the prepared norfloxacin semisolid formulation was found to be in good agreement with marketed Silver Sulfadiazine 1% cream, USP. CONCLUSIONS: These findings suggest formulations containing norfloxacin and metronidazole may also prove as an effective alternative for existing remedies in the treatment of bacterial infections and burn wounds.

Effect of bixin and norbixin on the expression of cytochrome P450 in HepG2 cell line.

Bixin and norbixin are the main components of annatto, which is extracted from Bixa orellana and largely used as natural colorant in the food and pharmaceutical industries. Annatto can enhance CYP1A and CYP2B activity in rats; however, the inducer effect has not been investigated in human cell lines. In this study, the ability of bixin and norbixin to induce the cytochrome P450 (CYP) enzymes was assessed in HepG2 human hepatoma cell line. HepG2 cells were treated with bixin and norbixin, and the expression of the CYP genes quantified by real-time reverse transcription polymerase chain reaction (RT-PCR). Expression of CYP1A1 and CYP1A2 was significantly increased by bixin treatment, while CYP2B6, 2C9, 2E1 and 3A4 were unaffected. Cells were treated with norbixin showed no inducer effect. The results suggest that the inducer potential of annatto is attributed to bixin, but not to norbixin, despite their similarities in molecular structure.

Evaluation of cytochrome P-450 concentration in Saccharomyces cerevisiae strains / Avaliação do citocromo P-450 na concentração de estirpes de Saccharomyces cerevisiae

Saccharomyces cerevisiae has been widely used in mutagenicity tests due to the presence of a cytochrome P-450 system, capable of metabolizing promutagens to active mutagens. There are a large number of S. cerevisiae strains with varying abilities to produce cytochrome P-450. However, strain selection and ideal cultivation conditions are not well defined. We compared cytochrome P-450 levels in four different S. cerevisiae strains and evaluated the cultivation conditions necessary to obtain the highest levels. The amount of cytochrome P-450 produced by each strain varied, as did the incubation time needed to reach the maximum level. The highest cytochrome P-450 concentrations were found in media containing fermentable sugars. The NCYC 240 strain produced the highest level of cytochrome P-450 when grown in the presence of 20 percent (w/v) glucose. The addition of ethanol to the media also increased cytochrome P-450 synthesis in this strain. These results indicate cultivation conditions must be specific and well-established for the strain selected in order to assure high cytochrome P-450 levels and reliable mutagenicity results.

Linhagens de Saccharomyces cerevisiae tem sido amplamente empregadas em testes de mutagenicidade devido à presença de um sistema citocromo P-450 capaz de metabolizar substâncias pró-mutagênicas à sua forma ativa. Devido à grande variedade de linhagens de S. cerevisiae com diferentes capacidades de produção de citocromo P-450, torna-se necessária a seleção de cepas, bem como a definição das condições ideais de cultivo. Neste trabalho, foram comparados os níveis de citocromo P-450 em quatro diferentes linhagens de S. cerevisiae e avaliadas as condições de cultivo necessárias para obtenção de altas concentrações deste sistema enzimático. O maior nível enzimático foi encontrado na linhagem NCYC 240 em presença de 20 por cento de glicose (p/v). A adição de etanol ao meio de cultura também produziu um aumento na síntese de citocromo P-450. Estes resultados indicam que as condições de cultivo devem ser específicas e bem definidas para a linhagem selecionada, garantindo assim elevados níveis de citocromo P-450 e, conseqüentemente, a confiabilidade nos testes de mutagenicidade.

Implicações clínicas de drogas antineoplásicas mutagênicas / Clinical implications of mutagenic antineoplastic drugs

A quimioterapia com uso de drogas citotóxicas tem sido rotina no tratamento de câncer, proporcionando significativo aumento na sobrevida dos pacientes tratados. As drogas utilizadas apresentam diferentes mecanismos de ação e efeitos tóxicos diretos, sendo a maioria mutagênica e/ou carcinogênica. Poucas informações sobre estes efeitos estão disponíveis na literatura, tratando principalmente dos antineoplásicos que atuam por alquilação de DNA, com poucos dados pertinentes a classes de fármacos com outros mecanismos de ação.