Microbiological Stability Research Articles

Stability Study Through Water Activity Measurements for Dispensed Powdered Raw Materials.

Holding times for raw materials are relevant since they enable us to understand the allowable time that a raw material can be kept under ideal storage conditions before the start of the manufacturing process without its quality attributes being affected. The quantification of water activity can be used as an indicator of the microbiological, physicochemical, and organoleptic stability of a specimen, since low water activity retards autohydrolysis and microbiological growth. The main purpose of this investigation was to test the stability of powdered raw materials for a maximum holding time of 8 days through water activity measurements. Thus microbiological, physicochemical, and organoleptic measurements were carried out in parallel and simultaneously to experimentally establish a relationship between the status of the water activity of processed raw materials and the microbiological, physicochemical, and organoleptic results. The raw materials were stored for a maximum holding time of 8 days, in accordance with United States Pharmacopeia monographs. For all the raw materials tested, water activity measurements were performed using the dew point chilled-mirror method on days 0, 3, and 8. On days 0 and 8, microbiological, physicochemical, and organoleptic assessments were performed. It was established that under these storage conditions, the processed raw materials exhibited water activity below 0.60 during the entire holding time. However, there were statistically significant differences in water activity levels between days 0, 3, and 8 (ANOVA P < 0.05). Despite observing statistically significant differences between days, the microbiological, physicochemical, and organoleptic features were within specification at those water activity levels below 0.60. Water activity below 0.60 does not allow the growth of microorganisms, and the organoleptic and physicochemical features remain unperturbed. The results indicate that water activity can be used as an indicator of the microbiological load and chemical stability of the raw materials tested. This research provides evidence that corroborates that water activity status may be used as a reliable indicator for the microbiological burden and physicochemical features of pharmaceutical material during stability studies.

Physicochemical analysis and antioxidant activity of stem and leaf extracts from Ocimum basilicum grow under in different cultivation conditions

The Ocimum basilicum species is widely used in folk medicine, as well as by the pharmaceutical industry and in the production of essential oils. Considering these aspects and highlighting the good adaptability of the species in the Brazilian Cerrado which originated from Asia, analysis of its physicochemical properties can lead to better product quality through improved physical-chemical and even microbiological stability, as well as the application of compounds that capture free radicals. Given this, physicochemical analyses regulated by the Adolfo Lutz Institute (2008), such as pH, titratable acidity, moisture, ash content, proteins, vitamin C, and lipids were performed; these analyses yielded unprecedented results, confirming its microbiological stability and promising results for antioxidant activities through crude extracts from both the leaf and stem, as well as ethyl acetate extracts from the leaf and methanol extracts from the stem, with over 90% activity.

Physicochemical and biological stability of diluted vedolizumab in intravenous infusion bags

IntroductionIntravenous vedolizumab is a widely used monoclonal antibody for outpatients with inflammatory bowel disease. Drug preparation is performed on the day of administration, but is time consuming, causing unnecessary in-hospital...

Development of a plant-based dessert using araticum pulp and chickpea extract: Physicochemical, microbiological, antioxidant, and sensory characterization.

The demand for plant-based products has increased in recent years, due to several aspects related to health and environmental consciousness. This study aimed to produce and characterize a plant-based dairy alternative dessert based on araticum pulp and chickpea extract without added sugar and fat. Three formulations were prepared: Formulation 1 (F1): 20% araticum pulp + 80% chickpea extract; Formulation 2 (F2): 30% araticum pulp + 70% chickpea extract; and Formulation 3 (F3): 40% araticum pulp + 60% chickpea extract. All formulations' chemical composition, sensorial characteristics, viscosity, total phenolic content, antioxidant activity, and microbiological stability were analyzed during 28 days of storage at 4°C and a relative humidity of 23%. Energetic value ranged from 64 to 71 kcal/100g, and carbohydrate content from 9.68 to 11.06, protein from 3.38 to 3.04, lipids from 1.41 to 1.60, ashes from 0.53 to 0.59 and crude fiber from 0.86 to 1.34 g/100g among the formulations. The increase in the proportion of araticum pulp in the formulations reduced moisture content by 1.2 to 2.1% (F1: 84.2, F2: 83.2, and F3: 82.4), protein content by 3 to 9% (F1: 3.3, F2: 3.2, and F3: 3.0), and pH value by 5.8 to 10.7% (F1: 5.50, F2: 5.18, and F3: 4.91), and increased the TSS by 1.1 to 1.3-fold (F1: 8.36, F2: 8.98, and F3: 10.63 º Brix), total phenolics content by 1.5 to 2.0-fold (F1: 4,677, F2: 6,943, and F3: 10,112 gallic acid μmol/L) and antioxidant activity by 1.8 to 2.8-fold (F1: 1,974, F2: 3,664, and F3: 5.523). During the 28 days of storage at 4°C, the formulations F1 and F2 showed better stability of phenolic compounds and antioxidant activity; however, the formulation F3 showed acceptable microbiological quality up to 28 days of storage, higher viscosity, 8 to 16-fold higher than the formulations F1 and F2, respectively (F1: 238.90, F2: 474.30, and F3:3,959.77 mPa.s), antioxidant capacity and better scores in sensory analysis. The present study showed that the plant-based dessert elaborated with araticum pulp and chickpea extract might be considered a potential dairy alternative product with high antioxidant activity, protein content, and a viscosity similar to yogurt; however, its sensory aspects need improvement.

Avaliação da segurança pré-clínica de um iogurte probiótico feito com polpa de tumbo (Passiflora tripartita Kunth)

Abstract A probiotic yogurt made from the pulp of the tumbo fruit (Passiflora tripartita Kunth) possesses antioxidant capacity, physicochemical and microbiological quality and stability; however, it needs to be safe for later studies of clinical functionality. The present study would be considered as a precursor to the preclinical safety evaluation of a functional food by in vivo toxicological testing. The study aimed to evaluate the preclinical safety of yogurt made from the pulp of the tumbo fruit (P. tripartita). The toxicological studies proposed were based on the OECD 423:2001 standard on Acute Oral Toxicity, performing the peroral administration of the probiotic yogurt at a dose of 2000 mg/kg one-time in a group of randomized male rats, for its evaluation during 14 days compared to a control group; and on the OECD 407: 2008 on Repeated Dose Oral Toxicity, a daily dose of 2000 mg/kg of the yogurt was administered for 28 days in male rats, considering the evaluation of their clinical, hematological and biochemical parameters, to determine any possible toxic effect produced by the probiotic formulation. The results showed that in both toxicological studies, no adverse alterations were detected in their clinical signs, relative organ weights and hematological and biochemical profiles. In addition, a possible improvement in the immunological status, liver function and hematological profile was evidenced as a finding. In conclusion, it was possible to establish knowledge on the preclinical safety of the formulation of a probiotic yogurt made with tumbo fruit pulp, obtaining a NOAEL (No Observed Adverse Effect Level) value higher than 2000 mg/kg body weight in male rats.

Effect of drying process on survival of environmental starter culture and nutritional value

Since Poland is one of the largest producers of rapeseed, the products of its processing – oil cake and rapeseed meal – could be promising alternatives in animal nutrition and, in the future, could also be used as food additives for humans. Fermentation, of these post-waste raw materials, eliminates the bitter taste and enriches the ferment with nutrients. Due to the fact that fermented rapeseed meal has a high water activity, it is possible to develop virtually all groups of microorganisms in it. Therefore, it is advisable to use a fixation method that will ensure the microbiological stability of the fermented product. The purpose of this study was to develop a starter culture for the fermentation of rapeseed meal and to investigate the effect of the drying process of fermented rapeseed meal on the survival rate of the starter culture. Fermented rapeseed meal was dried at 48°C for 33 h. After 30 days of storage of the dried meal, the survival rate of the starter culture was checked. Since the fermented rapeseed meal was meant to be used as feed for pigs, a low-temperature drying process was used in the study. Drying the fermented rapeseed meal made it possible to stabilize the product and allowed it to be stored safely, without signs of mold, for 30 days. The drying temperature of 48°C did not negatively affect the biological value of the nutrients or the survival of the starter culture in dried rapeseed meal after rehydration.

Correlation of Microbiological Stability with Redox Processes in White Wines

Correlation of Microbiological Stability with Redox Processes in White Wines

Bioburden Analysis and Microbiological Stability of Municipal Distribution System through Examination of Transformed Total Microbial Count Dataset

Bioburden Analysis and Microbiological Stability of Municipal Distribution System through Examination of Transformed Total Microbial Count Dataset

Microwave Treatment vs. Conventional Pasteurization: The Effect on Phytochemical and Microbiological Quality for Citrus-Maqui Beverages.

This study uncovered the impacts of microwave (MW) treatments compared to conventional pasteurization (TP) on the quality of functional citrus-maqui beverages, with added sucrose or stevia. The influence of these thermal treatments on the microbiological burden and phytochemical composition was determined by processing under two MW power levels (600 W and 800 W) and TP at 85 °C for 15 s for 60 days at room temperature (20 °C). The results indicated that, beyond the microbiological quality achieved in the juices treated by both MW and TP technology, there were no differences among the treatments regarding the stability of vitamin C, anthocyanin, and flavanone concentrations. However, anthocyanins were more stable in those beverages with sucrose added, rendering a better red color. Besides, all treatments ensured microbiological stability throughout the entire storage time. In conclusion, MW treatment could be considered as an alternative to TP, which ensures microbial safety, protecting functional compounds associated with health effects.

Application of Plant Ingredients for Improving Sustainability of Fresh Pasta

Pasta is a low-cost and easy-to-prepare food product. By using fresh pasta, the drying process is omitted, which represents significant energy and financial savings, but the durability of such pasta is very limited. The addition of plant materials (parsley, oregano, thyme, cinnamon, nettle, spinach, and carob) to the dough affects the microbiological stability and thus the durability of the fresh pasta, which can then be stored longer in the refrigerator without the need to freeze the product. With significant energy savings due to the omission of the drying and freezing processes, extending the shelf life of the pasta will contribute to the reduction of food waste and thus contribute to a more sustainable production system. The aim of this work was to examine the possibility of producing fresh pasta with the addition of plant materials from the perspectives of technological and sensory quality, as well as microbiological composition. The incorporation of plant materials (10 g/100 g) decreased water absorption and had no effect on optimal cooking time. Thyme-enriched pasta had significantly lower (p &lt; 0.05) cooking loss (3.34%) than the control sample (4.12%). In cinnamon-, spinach-, and parsley-enriched pasta, an appealing colour and pleasant smell and taste were achieved. Cinnamon and carob proved to have the most favourable effect on the microbiological quality (reduction in mesophilic, Enterobacteriaceae, and yeast counts), followed by spinach (reduction in mould count). For cinnamon-enriched pasta, the best technological (optimal cooking time of 3.23 min; cooking loss of 4.41%; firmness of 531.94 g) and sensory and microbiological quality were achieved; thus, cinnamon proved to be the preferred natural preservative for the production of enriched pasta.

ANALYSIS OF APPLYING SURFACE WATER TREATMENT TECHNOLOGY WHEN USING CHLORINE DIOXIDE AT WATER SUPPLY PLANTS

The results of the conducted research made it possible to establish that in EU countries chlorine dioxide (CD) is more often used for secondary or final disinfection of drinking water. By-products of this process are chlorites and chlorates, which are subject to control in the drinking water of all EU countries. Aldehydes and carboxylic acids can also be formed in drinking water, which leads to a decrease in the microbiological stability of tap water. Ozonation and filtration using a carbon filter are used in the final stage of drinking water purification, which contributes to a significant reduction in the dose of CD and water contamination with toxic chlorites. In the case of pre-oxidation of water with sodium hypochlorite, the largest amount of chlorites and chlorates is formed, while in the case of using potassium permanganate for the same purpose, the need for CD and the amount of chlorites and chlorates in drinking water reduced. Chlorination of natural water that has undergone CD pre-oxidation leads to complete oxidation of the chlorites that have formed, increases the effectiveness of disinfection, and provides a bacteriostatic effect in the distribution network. During 2021-2022, when using CD for the treatment of drinking water at the Dniprovska WTP in Kyiv it was established that the process of treating natural water with CD is accompanied by the formation of its by-products, mainly toxic chlorites, the levels of which depend on the applied doses of CD and are the lowest in winter, while the largest ones are observed in summer and do not always reach regulatory values (0,2 mg/l) and range up to 0,7 mg/l, which corresponds to the WHO recommended standard for this substance in drinking water. Italian scientists focus their attention on the fact that during the first years of using CD at each water supply station, optimal conditions must be ensured for the safe and effective use of this reagent. Therefore, CD is becoming widespread in the EU countries and Ukraine for the treatment of tap drinking water; it is an alternative method of water effective disinfection at water supply stations with traditional surface water purification technology. Using such a method for treating surface water requires a preliminary pilot experiment and should be carried out along with an analysis of the feasibility of using the methods for preliminary and/or final purification of drinking water from organic substances and additional disinfection. Today, based on experimental and natural studies, it is relevant to expand knowledge about the properties of CD in the case of its use in drinking water supply for the treatment of surface water with a high content of organic substances.

Palatability and Stability Studies to Optimize a Carvedilol Oral Liquid Formulation for Pediatric Use.

Carvedilol (CARV) is a blocker of α- and β- adrenergic receptors, used as an "off-label" treatment for cardiovascular diseases in pediatrics. Currently, there is no marketed pediatric-appropriate CARV liquid formulation, so its development is necessary. Palatability (appreciation of smell, taste, and aftertaste) is a key aspect to be considered during the development of pediatric formulations since only formulations with good palatability also have adequate acceptability in this population. Consequently, the aim of this research was to assess the palatability and acceptability of different CARV formulations using an in vivo taste assessment (ID Number PR103/22) in order to select the highest palatability-rated CARV formulation. The preparation of CARV formulations was based on a reference 1 mg/mL CARV solution, which contains malic acid as a solubilizing agent. Subsequently, sucralose and flavoring agents were added and mixed until complete dissolution to the corresponding formulations. Adult volunteers participated in this study and evaluated the taste and odor of various CARV formulations through a questionnaire and a sensory test. The mean palatability score, measured on a 10-point scale, increased from 1.60 for the unflavored control to 7.65 for the highest-rated flavored formulation. Moreover, the bitterness of the optimized CARV formulation was reduced from 66.67% to 17.86%, and the taste pleasantness was increased from 25/100 to 73/100. This optimized CARV formulation contains a sweetening agent, sucralose, in addition to two flavoring agents at appropriate concentrations for pediatrics. Furthermore, the physicochemical and microbiological stability of the optimized CARV formulation were evaluated for 6 months at 25, 30, and 40 °C, in addition to in-use stability for 15 days at 25 °C, whose results were confirmed. Thus, we successfully developed a palatable CARV liquid solution that contains excipients appropriate for pediatrics and is stable under the studied conditions.

Microbiological quality and efficacy of preservatives in marigold-based skin care products

&amp;lt;p&amp;gt;The microbiological stability of cosmetic products is crucial, especially in products with high water content, such as creams. Therefore, preservatives are used in order to protect consumers from harmful pathogens that would otherwise invade the cosmetics. Despite their function, the addition of preservatives can be considered controversial in the cosmetics industry. Parabens are frequently used synthetic preservatives in various industries. According to regulatory directives concerning cosmetics (Cosmetic Directive by the European Commission) usage of some parabens (methylparaben, propylparaben, butylparaben, and ethylparaben) is safe and permitted in allowed concentrations. On the other hand, the European Commission prohibited the use of isopropylparaben, isobutylparaben, phenylparaben, benzylparaben and pentylparaben. Therefore, a comprehensive stability study was conducted to evaluate the influence of paraben-based preservative (Gujsol-1&amp;lt;sup&amp;gt;&amp;amp;reg;&amp;lt;/sup&amp;gt;, INCI name: Phenoxyethanol, Methylparaben, Ethylparaben, Propylparaben, Butylparaben) and potassium sorbate in order to preserve plant extracts-based skin-care products, Day and Night creams with marigold extract. Previously, mentioned skin-care products were preserved with the preservative Dekaben C&amp;lt;sup&amp;gt;&amp;amp;reg;&amp;lt;/sup&amp;gt;, which contained paraben mixture with banned isobutylparaben. All tested formulations showed favorable texture and sensory characteristics, desirable mild acidic pH values, satisfactory physical stability and appropriate microbiological quality at the initial point, as well as after storage at elevated temperature or at cyclic stress test conditions and at room temperature during two years. In addition, both preservatives significantly reduced the number of inoculated microorganisms during the challenge test. It can be concluded that potassium sorbate in plant-based creams could be an efficient alternative to paraben-based preservatives.&amp;lt;/p&amp;gt;

Astringent and non‐astringent persimmon cremogenates made with different thickeners

SummaryDue to the surplus in the production of ‘Rojo Brillante’ persimmon in Spain, there is great interest in developing products made from this fruit that can take full advantage of production peaks. However, heat treatment can reverse the astringency, limiting the diversity of products derived from persimmon. The aim of this study was to characterise physicochemically astringent and non‐astringent persimmon cremogenates subjected to pasteurisation and elaborated with different thickeners (guar gum, sodium alginate and pectin). Several aspects were specifically analysed: the evolution during the storage of the soluble solid content, water, total phenols, antioxidant capacity, optical and mechanical properties, as well as the microbiological stability. The sensory acceptability of the selected cremogenates was also evaluated. The results showed that the final colour of the samples depended on the initial level of astringency of the raw material; the non‐astringent persimmons were much darker (L* ≈ 40–50) than astringent persimmons (L* ≈ 65–70), and the type of thickener used had no effect and led to no difference. Furthermore, the cremogenate was harder (F ≈ 20–120 N) when astringent persimmons were used. In astringent cremogenates the thickeners evaluated help in reducing the total phenol content after 3 months of storage in 40% when compared to the control. The heat treatment applied (70 °C, 30 min) did not reverse the astringency, so this type of cremogenate could be a commercial outlet for the waste or surplus of this fruit. In this regard, non‐astringent persimmons with pectin would be recommended for the preparation of cremogenates from this fruit since they were also those that the scored best in the sensory analysis.

Strategies to extend the shelf life of sheep and goat cheese whey under refrigeration: Nisin, bioprotective culture, and acidification

The valorization of sheep and goat cheese whey are important from economic, social and environmental perspectives. However, their low microbiological and physical stabilities are major challenges, especially for artisanal productions. In this study, the effectiveness of nisin addition, bioprotective culture (Lacticaseibacillus casei) inoculation and direct acidification (pH 2.5–4.5) was evaluated to improve the stability of pasteurized (75 °C/5 min) sheep and goat cheese whey. All strategies were effective in controlling the native microbial population, with minimal or no change in the pH or acidity during 28 days/7 °C, whereas samples only pasteurized reached counts of up to 8 log CFU/mL. Phase separation occurred in all samples, but at different rates and intensities. Acidification at pH 3.5 and 4.5 resulted in higher creaming rates (up to 30%), even without change in fat globule size, and sedimentation (up to 6%), due to protein particle agglomeration - that increased D[3,2] values by up to 27% and reduced the specific surface area by around 20%. Conversely, acidification at pH 2.5 or the addition of nisin or L. casei resulted in samples with smaller particle size and better stability to creaming and sedimentation. The results indicated that nisin addition or L. casei inoculation are possible strategies to improve the shelf life of sheep and goat pasteurized whey, which can be used even by artisanal producers, and thus contributing for their valorization.

Influence of Salting and Ripening Conditions on the Characteristics of a Reduced-Fat, Semi-Hard, Sheep Milk Cheese.

This study aimed to assess the effect of salting and ripening conditions on the features of sheep milk, reduced-fat, semi-hard cheese. Eight groups of cheese, with an average fat content of ≅10.5%, moisture on non-fat substances (MNFS) ≅ 56%, a protein-to-fat ratio of 2.9 and pH 5.1, were manufactured and analyzed throughout ripening. The experimental factors were the salting method (brine- or dry-salting), the salt content (control- and reduced-salt) and the ripening temperature sequence (11 or 18 °C at the 3rd and 4th week). Brine-salted cheese exhibited significantly more adequate (p < 0.05) textural and organoleptic characteristics compared to its dry-salted counterpart, i.e., lower hardness, gumminess and adhesiveness, with higher lightness and flavor scores. The mean salt reduction from 2.1 to 1.6% exhibited significant effects (p < 0.05), i.e., increased moisture and MNFS, decreased hardness, gumminess, chewiness and adhesiveness, and increased lightness and meltability of cheese without affecting the microbiological stability or impairing the organoleptic parameters. Ripening at 18 °C at weeks 3-4 significantly increased (p < 0.05) proteolysis and concentrations of lactic and citric acid without affecting meltability, textural or organoleptic features. In conclusion, brine-salting, salt reduction by 20% and the elevation of temperature at a particular ripening period improved the characteristics of this type of reduced-fat sheep milk cheese.

Study of the Oxidative and Microbiological Stability of Nitrite-Reduced, Vacuum-Packed, Refrigerated Lamb Sausages Supplemented with Red Propolis Extract.

Vacuum-packed lamb sausages with or without red propolis extract and a reduced sodium nitrite content were evaluated for oxidative and microbiological stability during storage for 21 days at 2 °C. The following treatments were evaluated: EN150 (control, base formulation (BF) + 500 mg/kg sodium erythorbate and 150 mg/kg sodium nitrite); EN75 (BF + 500 mg/kg sodium erythorbate and 75 mg/kg sodium nitrite); P1N75 (without the addition of erythorbate, BF + 1800 mg/kg propolis extract and 75 mg/kg sodium nitrite); and P2N75 (without the addition of erythorbate, BF + 3600 mg/kg propolis extract and 75 mg/kg sodium nitrite). Analyses were conducted to characterize the samples on day 0 with respect to the proximate composition (moisture, protein, fat, and ash) and sensory acceptance. Stability during refrigerated storage was evaluated on days 0, 7, 14 and 21 for the parameters pH, color profile (L*, a*, and b*), TBARs index (oxidative stability) and microbiological count of aerobic psychrotrophic microorganisms. Texture profile, cooking weight loss (WLC), peroxide index and free fatty acids were evaluated on days 0 and 21. The treatments with propolis and reduced nitrite (EN150 and P1N75) showed a red color intensity (a*) similar to the treatment with erythorbate and the same nitrite content (EN75) at the end of storage, maintaining the characteristic reddish color of the sausages. The extract slowed down lipid oxidation during storage, especially P2N75, which showed the lowest level of TBARS (0.39 mg MDA/kg) and the peroxide index (2.13 mEq g O2) on day 21. The residual nitrite value in EN75 was the lowest (p < 0.05) on day 21, showing that synthetic antioxidants are more efficient than the extract in nitrite reduction reactions. The results for the counts of psychrotrophic microorganisms showed that the extract did not have the expected antimicrobial effect on the growth of this microorganisms, and leveling the results revealed no differences (p < 0.05) between the treatments. Despite the red propolis extract not showing a significant antimicrobial improvement in lamb sausages, it can be considered a healthy option with good prospects for replacing synthetic antioxidants with a natural product.

A Quality Assessment of Strawberry Nectar Stabilized by Thermal and High-Pressure Processing Conditions

This study is aimed at evaluating the quality of strawberry nectar following high-pressure processing (HPP) at different pressure levels (400, 500, and 600 MPa for 3 minutes) and thermal pasteurization (TT) at 75°C for 15 s. Key parameters include total colour difference ( Δ E ∗ ), aparent viscosity, colour analysis via CIELAB coordinates, and pH. Additionally, residual enzymatic activity (RA%) of polyphenol oxidase (PPO) and peroxidase (POD) was measured. Strawberry nectar (12°Brix) was prepared and subjected to processing, with thermal treatment in 50 mL tubes and HPP in 40 mL polyethylene bags. Samples were stored under refrigeration during 21 days, with microbial analysis conducted to assess microbiological stability during storage. TT exhibited a more pronounced reduction in total aerobic microbial count (TAMC) compared to HPP, which showed no detectable yeast and mould. Apparent viscosity varied among samples, with HPP at 600 MPa displaying a significant increase of 52.1% compared to the control. The pseudoplastic behavior, characterized by n values lower than 1, was consistent across all treatments. TT led to a reduction in L ∗ brightness value during storage, whereas HPP-treated samples underwent colour changes over time with Δ E ∗ of 3.1 for 400 MPa, 3 minutes, at 21 days. For PPO and POD, the 600 MPa treatment exhibited the highest inhibition (44% and 4% RA, respectively). This comprehensive study provides insights into how different HPP processing conditions affect the quality attributes, enzymatic activity, and microbiological stability of strawberry nectar during production and refrigerated storage. The research’s significance lies in its holistic comparison of HPP with traditional thermal pasteurization, offering valuable information for both industry and consumers.

Optimization, Formulation, and Stability of Topical Rapamycin Used for Rare Tuberous Sclerosis Disease: from Ointment to Liposomes

IntroductionTopical rapamycin has been established as an effective and safe therapy for facial angiofibromas in tuberous sclerosis. Different formulations have been tested for this skin disease, most using an ointment as a vehicle.PurposeTo improve the classical formulation of topical rapamycin and to determine the validity period of the proposed options based on chemical, physical, and microbiological stability studies.MethodsFour different 0.4% rapamycin formulations were prepared (ointment, emulsion, gel, and liposomes). The stability studies for each formulation over 56 days were as follows: (1) chemical: extraction with different solvents and high-performance liquid chromatography assay; (2) physical: pH, uniformity, extensibility, absence of crystals, absence of phase separation, and only for liposomal formulation, particle size, zeta potential, and encapsulation efficiency were determined; and (3) microbiological: culture samples in blood-agar media.ResultsOnly liposomes were chemically, physically, and microbiologically stable after 8 weeks. Ointment, emulsion, and gel formulations lost their chemical or physical stability before 56 days.ConclusionsThe authors describe four new formulations to improve the previous treatment for facial angiofibromas in tuberous sclerosis. The liposome-based formulation was the most appropriate according to chemical, physical, and microbiological stability studies. However, it would be necessary to carry out clinical studies to ensure the effectiveness and safety of this formulation and also guarantee an improvement in the quality of life of patients.

The Use of Gaseous Ozone to Reduce the Microbial Load of Rhubarb (Rheum L.) Petioles as an Additive to Craft Wheat Beers

Abstract Rhubarb (Rheum rhaponticum L.) is a valuable source of active components responsible for laxative, antibacterial, diuretic, anti-inflammatory and anti-cancer properties. On the other hand, ozone being an allotropic form of oxygen, due to its potential is a powerful antimicrobial agent. Treatment of rhubarb petioles with gaseous ozone, especially at a concentration of 50 ppm, for 30 minutes had a positive result on the microbiological stability and quality of the finished material. Sensory evaluation of prepared beers enriched without ozonated and ozonated rhubarb pulp showed that wheat beer with the addition of ozonated (50 ppm) rhubarb pulp was characterized by a balanced aroma and taste. The physico-chemical analysis of wheat beers demonstrated that the increasing concentration of ozone had an impact on, among others, increased the degree of final real attenuation (by 21.97%), decreased pH (by 18.43%) and energy value (by 36.30%), but had a negative impact on the content of ethyl alcohol (by 17.32%) compared to the control beer. Among the analyzed beers enriched with rhubarb, the beer product with the addition of ozonated (50 ppm) rhubarb was the most microbiologically stable. The research shows that wheat beers enriched with fragmented rhubarb can be a new trend to expand the range of wheat beers, and the use of gaseous ozone, especially at a concentration of 50 ppm for 30 minutes, can be a trend to extend the microbiological stability of beers, especially craft beers.