Nanoreduction as a technology to exploit β-Glucan from cereal and fungal sources for enhancing its nutraceutical potential

Glucans and applications in drug delivery

Glucan is a natural polysaccharide widely distributed in cereals and microorganisms that has various biological activities, including immunomodulatory, anti-infective, anti-inflammatory, and antitumor activities. In addition to wide applications in the broad fields of food, healthcare, and biomedicines, glucans hold promising potential as drug delivery carrier materials or ligands. Specifically, glucan microparticles or yeast cell wall particles are naturally enclosed vehicles with an interior cavity that can be exploited to carry and deliver drug payloads. The biological activities and targeting capacities of glucans depend largely on the recognition of glucan moieties by receptors such as dectin-1 and complement receptor 3, which are widely expressed on the cell membranes of mononuclear phagocytes, dendritic cells, neutrophils, and some lymphocytes. This review summarizes the chemical structures, sources, fundamental properties, extraction methods, and applications of these materials, with an emphasis on drug delivery. Glucans are utilized mainly as vaccine adjuvants, targeting ligands and as carrier materials for various drug entities. It is believed that glucans and glucan microparticles may be useful for the delivery of both small-molecule and macromolecular drugs, especially for potential treatment of immune-related diseases.

Cereal β-d-Glucans in Food Processing Applications and Nanotechnology Research

Cereal (1,3)(1,4)-β-d-glucans, known as β-d-glucans, are cell wall polysaccharides observed in selected plants of grasses, and oats and barley are their good natural sources. Thanks to their physicochemical properties β-d-glucans have therapeutic and nutritional potential and a specific place for their functional characteristics in diverse food formulations. They can function as thickeners, stabilizers, emulsifiers, and textural and gelation agents in beverages, bakery, meat, and extruded products. The objective of this review is to describe the primary procedures for the production of β-d-glucans from cereal grains, to define the processing factors influencing their properties, and to summarize their current use in the production of novel cereal-based foods. Additionally, the study delves into the utilization of β-d-glucans in the rapidly evolving field of nanotechnology, exploring potential applications within this technological realm.

Process optimization for spray dried Aegle marmelos fruit nanomucilage: Characterization, functional properties, and in vitro antibiofilm activity against food pathogenic microorganisms

Recently, mucilage extraction from plant sources has been remarkably explored due to its potential applications. Several underutilized fruits such as Aegle marmelos are the potential source of mucilage that can be utilized for agri-food-pharma applications. Therefore, in this study, we explored vital functional and antimicrobial properties of Aegle marmelos nanomucilage. Spray drying conditions such as inlet temperature, feed flow, and atomization speed were optimized to assess the influence on yield and moisture content using response surface methodology. In addition, during the optimized spray drying conditions, the maximum mucilage yield was 16.23 % (w/w). The particle size (178.4 ± 5.06 nm) at the nanoscale, polydispersity index (0.432), and zeta potential (-16.4 ± 1.14 mV) confirmed the stability of the nanomucilage. Moreover, the spray-dried nanomucilage powder exhibited high thermal stability (55.70 J) and excellent industrially important techno-functional properties with water-holding capacity (8.01 ± 0.04 g/g), oil-holding capacity (3.43 ± 0.7 g/g), emulsifying capacity (91.50 ± 0.78 %), emulsifying stability (92.65 ± 0.46 %), solubility (89.36 ± 1.69 %), and foaming capacity (16.13 ± 0.41 %). Moreover, the powder showed strong antibiofilm activity against food-pathogenic bacteria, including Escherichia coli (73.52 ± 1.14 %) and Staphylococcus aureus (79.57 ± 1.23 %), with minimum inhibitory concentrations of 3.125 mg/mL and 1.562 mg/mL respectively. Overall, based on the above findings the spray-dried powder of Aegle marmelos fruit nanomucilage could be utilized as a potential functional ingredient in various food products formulations.

Preparation of Albatrellus ovinus β-Glucan Microparticles with Dectin-1a Binding Properties

Fungal β-glucans are compounds with the potential to activate the innate immune system, in part through binding to the receptor dectin-1. In the present study, small-scale methods for preparing dectin-1a binding microparticles from Albatrellus ovinus alkali-soluble β-glucans were investigated. Mechanical milling was time-consuming and yielded large particles with wide size distributions. Precipitation was more successful: the β-glucan was dissolved in 1 M NaOH, diluted, and precipitated in 1:1 mol equiv HCl. This yielded particles in sizes ranging from 0.5-2 μm. The dectin-1a binding activity was determined using HEK-Blue reporter cells. The prepared particles were able to bind to dectin-1a to the same extent as baker's-yeast-derived β-glucan particles. The precipitation method was convenient as a quick method for small-scale preparation of β-glucan microparticle dispersions from mushroom β-glucans.

Fungal β-Glucan-Based Nanotherapeutics: From Fabrication to Application

Fungal β-glucans are naturally occurring active macromolecules used in food and medicine due to their wide range of biological activities and positive health benefits. Significant research efforts have been devoted over the past decade to producing fungal β-glucan-based nanomaterials and promoting their uses in numerous fields, including biomedicine. Herein, this review offers an up-to-date report on the synthetic strategies of common fungal β-glucan-based nanomaterials and preparation methods such as nanoprecipitation and emulsification. In addition, we highlight current examples of fungal β-glucan-based theranostic nanosystems and their prospective use for drug delivery and treatment in anti-cancer, vaccination, as well as anti-inflammatory treatments. It is anticipated that future advances in polysaccharide chemistry and nanotechnology will aid in the clinical translation of fungal β-glucan-based nanomaterials for the delivery of drugs and the treatment of illnesses.

Effect of pearling on nutritional value of highland barley flour and processing characteristics of noodles

Highland barley is increasingly recognized as its nutritional benefits but its structure restricts the development and utilization in the food industry. The quality of highland barley products may be impacted by pearling, an essential step before the hull bran is consumed or further processed. The nutrition, function and edible qualities of three highland barley flour (HBF) with different pearling rates were assessed in this study. The content of resistant starch was the highest when the pearling rate of QB27 and BHB was 4%, while 8% of QB13. Un-pearled HBF showed higher DPPH, ABTS and superoxide radicals inhibition rates. The break rates of QB13, QB27 and BHB obviously decreased from 51.7%, 53.3% and 38.3% to 35.0%, 15.0% and 6.7% respectively at 12% pearling rate. PLS-DA model further attributed the improvement of pearling on noodles quality to the alteration of resilience, hardness, tension distance, breaking rate and water absorption of noodles.

Upscaling of Apple By-Product by Utilising Apple Seed Protein as a Novel Wall Material for Encapsulation of Chlorogenic Acid as Model Bioactive Compound

Encapsulation is a versatile technique used to protect sensitive bioactive compounds under gastrointestinal conditions. In this study, nanoencapsulation of chlorogenic acid into the apple seed protein matrix was performed using the green technique ultrasonication to protect it from harsh gastric conditions and increase its biological activity and bioavailability upon digestion. Both nano (Nano-Chl) and native capsules (NT-Chl) were characterised by particle size, charge, structure, and morphology. The encapsulation efficiency, release behaviour, antioxidant and antidiabetic properties were also evaluated. The experimental results show that the particle size of the NT-Chl and Nano-Chl was found in the range of 1.4 µm to 708 nm. The encapsulation efficiency was found to be 69% and 80% for NT-Chl and Nano-Chl, respectively. Furthermore, an in vitro digestion study revealed that Nano-Chl showed controlled-release behaviour under simulated intestinal conditions in comparison to NT-Chl. Moreover, Nano-Chl showed enhanced antioxidant and antidiabetic activity in comparison to NT-Chl after simulated digestion. It was concluded that the protein from apple seeds could be utilised as a functional ingredient itself or as a wall material for the encapsulation of sensitive bioactive compounds. Furthermore, these encapsulated particles can be fortified into different food formulations for the development of functional food.

Effect of acid hydrolysis on the structural and antioxidant characteristics of β-glucan extracted from Qingke (Tibetan hulless barley)

In this study, we explored the effect of acid hydrolysis on the molecular, structural, rheological, thermal, and antioxidant characteristics of Qingke β-glucan. The acid hydrolysis reduced the molecular weights of β-glucans from 510 to 155 KDa. The results of the structural analysis by nuclear magnetic resonance (NMR) spectroscopy, X-ray diffraction, and fourier transforms infrared (FTIR) spectroscopy indicated that acid hydrolysis did not change the primary functional groups of β-glucans. The rheological behavior of β-glucan without and with acid hydrolysis can be described as pseudoplastic and Newtonian, respectively. The DSC curves of the β-glucans with high molecular weights showed the highest transition temperature. The 2, 2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical cation scavenging activity and the reducing power of soluble β-glucans in Qingke showed a dose-dependent pattern. Meanwhile, the antioxidant activities of Qingke β-glucan of different molecular weights were similar. This study demostrated that the acid hydrolysis almost have no effect on antioxidant activity of Qingke β-glucans.

Encapsulation of Catechin into β-Glucan Matrix Using Wet Milling and Ultrasonication as a Coupled Approach: Characterization and Bioactivity Retention

In this study, the nanoencapsulation of catechin into the β-glucan matrix from oats [O-Glu (C)] and barley [B-Glu (C)] was performed using the coupled approach of ultrasonication and wet milling. The nanoencapsulated catechin was characterised by particle size distribution, surface charge, SEM, and FTIR. The particle size was found to be 200 nm and 500 nm while zeta potential was found −27.13 and −24 mV for O-Glu (C) and B-Glu (C), respectively. The encapsulation efficiency of O-Glu (C) and B-Glu (C) was found to be 86.5% and 88.2%. FTIR and SEM revealed successful entrapment of catechin in β-glucan. The encapsulated capsules showed sustainable release during simulated gastrointestinal conditions. Moreover, both O-Glu (C) and B-Glu (C) showed that biological activity such as lipase inhibition activity and antioxidant assay were retained after in vitro digestion. It was concluded that O-Glu (C) and B-Glu (C) can be used as functional ingredients effectively in food as well as in the pharmaceutical field.

Ultrasonication as an innovative approach to tailor the apple seed proteins into nanosize: Effect on protein structural and functional properties

In this study, protein was extracted from the apple seed flour using alkali-acid precipitation method. The main objective of this study was to evaluate the impact of ultrasonication on structural and techno-functional properties of apple seed protein. Both native (N-protein) and ultra-sonicated protein (US-protein) were characterized for size, zeta potential, structure, protein pattern, crystallinity, thermal stability and functional properties. The results revealed that the hydrodynamic diameter of N-protein and US-protein was 1.2 µm and 484 nm while zeta potential was -11 and -19 mV, respectively. Fourier transform infrared-spectroscopy and X-ray diffraction analysis showed change in the conformational characteristics and functional groups of proteins after nano-reduction. SEM revealed change in the surface morphology of protein molecule upon ultrasonication. Differential scanning calorimetry showed decreased denaturation temperature for US-protein compared to N-protein . SDS-PAGE depicted no change in protein pattern upon ultrasonication. Ultrasonicated protein exhibited increased functional properties like emulsification, foaming, hydrophobicity and oil absorbing properties and hence can be efficiently used as functional ingredient in food and nutraceutical industry.

Ferulic acid loaded pickering emulsions stabilized by resistant starch nanoparticles using ultrasonication: Characterization, in vitro release and nutraceutical potential

The use of starch based nanoparticles have gained momentum in stabilizing pickering emulsions for it's numerous advantages. In present study resistant starch (RS) was isolated from lotus stem using enzymatic digestion and subjected to nanoprecipitation and ultrasonication to yield resistant starch nanoparticles (RSN). RSN of varying concentrations (2%, 10% and 20%) were used to stabilize the flax seed-oil water mixture to form pickering emulsions. The emulsions were used to nanoencapsulate ferulic acid (FA) - a well known bioactive via ultrasonication. The emulsions were lyophilized to form FA loaded lyophilized pickering emulsion (FA-LPE). The FA-LPE (2%, 10 % and 20%) were characterized using dynamic light scattering (DLS), light microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), atomic force microscopy (AFM) and attenuated total reflectance fourier transform infra-spectroscopy (ATR-FTIR). AFM showed FA-LPE as spherical droplets embedded in the matrix with maximum peak height of 8.47 nm and maximum pit height of 1.69 nm. SEM presented FA-LPE as an irregular and continuous surface having multiple folds and holes. The ATR-FTIR spectra of all the samples displayed peaks of C = C aromatic rings of FA at 1600 cm^-1 and 1439 cm^-1, signifying successful encapsulation. In vitro release assay displayed more controlled release of FA from FA-LPE (20%). Bioactivity of FA-LPE was evaluated in terms of anti-cancer, anti-diabetic, angiotensin converting enzyme (ACE) inhibition and prevention against oxidative damage under simulated gastro-intestinal conditions (SGID). The bioactivity of FA-LPE (20%) was significantly higher than FA-LPE (2%) and FA-LPE (10%). Key findings reveal that pickering emulsions can prevent FA under harsh SGID conditions and provide an approach to facilitate the design of pickering emulsions with high stability for nutraceutical delivery in food and supplement products.

Ultrasonics as a tool for development of pine-needle extract loaded bee wax edible packaging for value addition of Himalayan cheese

In the present study, Himalayan cheese, kradi was coated with beeswax loaded with pine needle extract (PNE) to increase its shelf life and nutraceutical potential. PNE was extracted via ultrasonication and incorporated into beeswax at concentrations, 2:1, 1:1, and 2:3 (grams of beeswax to mL of PNE). The dispersion of PNE in the coatings was carried out using an ultrasonic probe at a frequency of 20 kHz for 15 min and at power rating of 500 W. The coatings were characterised using scanning electron microscopy, light microscopy, dynamic light scattering (DLS), fourier transmission infrared spectroscopy. DLS revealed a hydrodynamic diameter and zeta potential of 12.11 ± 0.41 µm and -19.32 ± 0.61 mV for coating loaded with highest concentration of PNE. The bioactivities of the coating including antioxidant, antidiabetic and antibacterial assays revealed significantly higher values with the increase in PNE concentration. Shelf life and sensory evaluation study including microbiological and sensory analysis revealed inhibition of mould growth and good score of texture and appearance with the increase in concentration of PNE. The study provides a future perspective for application of beeswax loaded PNE coatings in cheese industry.

β-Glucan from mushrooms and dates as a wall material for targeted delivery of model bioactive compound: Nutraceutical profiling and bioavailability

Rutin was nano-encapsulated in date [En-Ru(D)] and mushroom [En-Ru(M)] β-glucan matrix to protect it from the harsh gastrointestinal environment and to enhance its bioavailability and biological activity upon digestion. The encapsulation was carried using green technology i.e., ultra-sonication. The En-Ru(D) and En-Ru (M) showed the hydrodynamic diameter of 314.04 and 482.21 nm with polydispersity index of 0.21 and 0.33. The in vitro release behaviour followed the Higuchi model. The antimicrobial activity of En-Ru(D) and En-Ru(M) were evaluated against gram negative E. coli (ATCC 25922) and gram positive (Staphylococcus aureus) bacteria. Furthermore, En-Ru(D) and En-Ru(M) exhibited increased bioavailability of rutin in intestinal fluid with retention of anti-obesity and antioxidant activities after digestion (p < 0.05). Therefore, β-glucan matrix can efficiently encapsulate flavonoids and regulate the release of functional bioactive ingredients in the simulated human digestive conditions.

Effect of thermal processing on the molecular, structural, and antioxidant characteristics of highland barley β-glucan

This present work evaluated the effect of heat fluidization, microwave roasting and baking treatment of highland barley (HB) on the molecular, structural, thermal and antioxidant characteristics of β-glucan. Fluorescence microscopy results showed that heat fluidization exhibited the greatest disruption effect on endosperm cell walls, resulting in the highest extractability (3.35 ± 0.06 g/100 g flour) and purity (92.67 ± 0.73%) of β-glucan. After HB thermal processing, the molecular weight and polydispersity index of β-glucan were respectively reduced by 3.68%-90.35% and 26.45%-39.83%, and its microscopic molecular morphology transformed from large sphere aggregate to alveolate gel network structure. Meanwhile, the structural elucidation by X-ray diffraction and infrared spectroscopy revealed that thermal processing induced the scission of polymeric chain and formation of lattice-type microgels without changing the primary functional groups of β-glucan. Furthermore, thermogravimetry and antioxidant results indicated the thermal stability and antioxidant activity of β-glucan were enhanced by thermal processing.

Innovative biosynthesis of silver nanoparticles using yeast glucan nanopolymer and their potentiality as antibacterial composite

Nanometals (NM) frequently possess potent antimicrobial potentials to combat various pathogens, but their elevated biotoxicity limits their direct applications. The biosynthesis of NM and their capping/conjugation with natural biopolymers can effectually enhance NM stability and diminish such toxicity. Yeast β-glucan (βG), from Saccharomyces cerevisiae, was extracted and transformed to nanoparticles (NPs) using alkali/acid facile protocol. The βG NPs were innovatively employed for direct biosynthesis of silver nanoparticles (Ag NPs) without extra chemical processes. The physicochemical assessments (Fourier-transform infrared, X-ray diffraction, and transmission electron microscopy) validated NPs formation, interaction, and interior capping of Ag NPs in βG NPs. The synthesized βG NPs, Ag NPs, and βG-Ag NPs composite were negatively charged and had minute particle sizes with mean diameters of 58.65, 6.72, and 63.88 nm, respectively. The NPs (plain Ag NPs and composited βG-Ag NPs) exhibited potent comparable bactericidal actions, opposing Gram⁺ (Staphylococcus aureus) and Gram^- (Escherichia coli, Salmonella Typhimurium, and Pseudomonas aeruginosa). Scanning micrographs, of treated S. aureus and S. Typhimurium with βG-Ag NPs, elucidated the powerful bactericidal actions of nanocomposite for destructing pathogens' cells. The inventive Ag NPs biosynthesis with βG NPs and the combined βG-Ag NPs nanocomposites could be impressively recommended as powerful antibacterial candidates with minor potential toxicity.