Polysaccharide-Based Carriers for Pulmonary Insulin Delivery: The Potential of Coffee as an Unconventional Source

Non-invasive routes for insulin delivery are emerging as alternatives to currently painful subcutaneous injections. For pulmonary delivery, formulations may be in powdered particle form, using carriers such as polysaccharides to stabilise the active principle. Roasted coffee beans and spent coffee grounds (SCG) are rich in polysaccharides, namely galactomannans and arabinogalactans. In this work, the polysaccharides were obtained from roasted coffee and SCG for the preparation of insulin-loaded microparticles. The galactomannan and arabinogalactan-rich fractions of coffee beverages were purified by ultrafiltration and separated by graded ethanol precipitations at 50% and 75%, respectively. For SCG, galactomannan-rich and arabinogalactan-rich fractions were recovered by microwave-assisted extraction at 150 °C and at 180 °C, followed by ultrafiltration. Each extract was spray-dried with insulin 10% (w/w). All microparticles had a raisin-like morphology and average diameters of 1-5 µm, which are appropriate for pulmonary delivery. Galactomannan-based microparticles, independently of their source, released insulin in a gradual manner, while arabinogalactan-based ones presented a burst release. The microparticles were seen to be non-cytotoxic for cells representative of the lung, specifically lung epithelial cells (A549) and macrophages (Raw 264.7) up to 1 mg/mL. This work shows how coffee can be a sustainable source of polysaccharide carriers for insulin delivery via the pulmonary route.

Mycotoxins’ Prevalence in Food Industry By-Products: A Systematic Review

The recovery of biomolecules from food industry by-products is of major relevance for a circular economy strategy. However, by-products’ contamination with mycotoxins represents a drawback for their reliable valorization for food and feed, hampering their application range, especially as food ingredients. Mycotoxin contamination occurs even in dried matrices. There is a need for the implantation of monitoring programs, even for by-products used as animal feed, since very high levels can be reached. This systematic review aims to identify the food by-products that have been studied from 2000 until 2022 (22 years) concerning mycotoxins’ contamination, distribution, and prevalence in those by-products. PRISMA (“Preferred Reporting Items for Systematic Reviews and MetaAnalyses”) protocol was performed via two databases (PubMed and SCOPUS) to summarize the research findings. After the screening and selection process, the full texts of eligible articles (32 studies) were evaluated, and data from 16 studies were considered. A total of 6 by-products were assessed concerning mycotoxin content; these include distiller dried grain with solubles, brewer’s spent grain, brewer’s spent yeast, cocoa shell, grape pomace, and sugar beet pulp. Frequent mycotoxins in these by-products are AFB1, OTA, FBs, DON, and ZEA. The high prevalence of contaminated samples, which surpasses the limits established for human consumption, thus limiting their valorization as ingredients in the food industry. Co-contamination is frequent, which can cause synergistic interactions and amplify their toxicity.

Polysaccharide-based formulations as potential carriers for pulmonary delivery - A review of their properties and fates

Polysaccharides can be elite carriers for therapeutic molecules due to their versatility and low probability to trigger toxicity and immunogenic responses. Local and systemic therapies can be achieved through particle pulmonary delivery, a promising non-invasive alternative. Successful pulmonary delivery requires particles with appropriate flowability to reach alveoli and avoid premature clearance mechanisms. Polysaccharides can form micro-, nano-in-micro-, and large porous particles, aerogels, and hydrogels. Herein, the characteristics of polysaccharides used in drug formulations for pulmonary delivery are reviewed, providing insights into structure-function relationships. Charged polysaccharides can confer mucoadhesion, whereas the ability for specific sugar recognition may confer targeting capacity for alveolar macrophages. The method of particle preparation must be chosen considering the properties of the components and the delivery device to be utilized. The fate of polysaccharide-based carriers is dependent on enzyme-triggered hydrolytic and/or oxidative mechanisms, allowing their complete degradation and elimination through urine or reutilization of released monosaccharides.

In vitro immunomodulatory activity of water-soluble glucans from fresh and dried Longan (Dimocarpus longan Lour.)

Longan (Dimocarpus longan Lour.) is a seasonal tropical fruit used by Chinese medicine in both fresh and dried pulp forms. Their polysaccharides have been reported to have biological activity. However, their composition and immune activity have not yet been disclosed. To fulfil this aim, hot water-soluble polysaccharides of fresh and dried longan pulp were fractionated according to their molecular weight by ultrafiltration (10, 50, 100 kDa cut off). The main polysaccharides recovered were 1,6-linked glucans branched at O-3 (4-8%), O-2 (1%), O-2,4 (0.1%), and O-3,4 (0.1%). The drying process promotes the solubility of the polysaccharides. These glucans from fresh and dried longan pulp have immunomodulatory activity, shown by in vitro phagocytosis, NO, TNF-α, and IL-6 macrophages production assays. They showed also to inhibit the inflammatory response induced by LPS. The immunological activity of these glucans seems to have different responses dependent on their molecular weight, related to the immune regulatory pathways.

Carbohydrates as targeting compounds to produce infusions resembling espresso coffee brews using quality by design approach

All coffee brews are prepared with roasted coffee and water, giving origin to espresso, instant, or filtered coffee, exhibiting distinct physicochemical properties, depending on the extraction conditions. The different relative content of compounds in the brews modulates coffee body, aroma, and colour. In this study it was hypothesized that a coffee infusion allows to obtain extracts that resemble espresso coffee (EC) physicochemical properties. Carbohydrates (content and composition) were the target compounds as they are organoleptically important for EC due to their association to foam stability and viscosity. The freeze-drying of the extracts allowed better dissolution properties than spray-drying. Instant coffee powders were obtained with chemical overall composition resembling espresso, although with lower lipids content. The extracts were able to produce the characteristic foam through CO₂ injection or salts addition. Their redissolution at espresso concentration allowed a viscosity, foamability and volatile profile representative of an espresso coffee, opening new exploitation possibilities.

In Vitro Hypocholesterolemic Effect of Coffee Compounds

(1) Background: Cholesterol bioaccessibility is an indicator of cholesterol that is available for absorption and therefore can be a measure of hypocholesterolemic potential. In this work, the effect of commercial espresso coffee and coffee extracts on cholesterol solubility are studied in an in vitro model composed by glycodeoxycholic bile salt, as a measure of its bioaccessibility. (2) Methods: Polysaccharide extracts from coffees obtained with different extraction conditions were purified by selective precipitation with ethanol, and their sugars content were characterized by GC-FID. Hexane extraction allowed us to obtain the coffee lipids. Espresso coffee samples and extracts were tested regarding their concentration dependence on the solubility of labeled 13C-4 cholesterol by bile salt micelles, using quantitative 13C NMR. (3) Results and Discussion: Espresso coffee and coffee extracts were rich in polysaccharides, mainly arabinogalactans and galactomannans. These polysaccharides decrease cholesterol solubility and, simultaneously, the bile salts' concentration. Coffee lipid extracts were also found to decrease cholesterol solubility, although not affecting bile salt concentration. (4) Conclusions: Coffee soluble fiber, composed by the arabinogalactans and galactomannans, showed to sequester bile salts from the solution, leading to a decrease in cholesterol bioaccessibility. Coffee lipids also decrease cholesterol bioaccessibility, although the mechanism of action identified is the co-solubilization in the bile salt micelles. The effect of both polysaccharides and lipids showed to be additive, representing the overall effect observed in a typical espresso coffee. The effect of polysaccharides and lipids on cholesterol bioaccessibility should be accounted on the formulation of hypocholesterolemic food ingredients.

The reproductive cycle of the oyster Crassostrea gasar

The purpose of this study was to analyze the reproductive cycle of the oyster Crassostrea gasar (= C. brasiliana) in the field and the laboratory. The reproductive cycle of the animals was evaluated in the field at Sambaqui Beach, Florianópolis, SC (27° 29′18″ S and 48° 32′12″ W) from May 2008 through November 2009. In July, the animals were in the resting stage. The early growth stage began in August and was followed by the late growth stage in October. In November and December, the oysters began to enter the mature stage. Females in spawning condition were predominant during these months. The stages of the reproductive cycle were positively associated with temperature (r=0.77, P<0.01) and negatively associated with salinity (r=−0.56, P=0.042). These findings demonstrated that increased temperature and reduced salinity influence the reproductive development of Crassostrea gasar. The condition index (CI) of the animals was also associated with the seawater temperature. The highest values of the condition index were observed during the months when the temperature of the seawater was gradually increasing. A laboratory experiment was performed to test the effect of salinity on the reproductive cycle of the oysters. The experiment was conducted in standardized tanks. The animals were conditioned using two salinities (24‰ and 34‰). The salinity regime influenced the development of the gonadal tissue of the oysters. A salinity of 24‰ produced greater reproductive development.

Horseradish peroxidase (HRP) as a tool in green chemistry

The horseradish peroxidase (HRP) potential in organic synthesis.