The effect of acid dextrinisation on enzyme-resistant starch content in extruded maize starch

Dual-action microparticles for ulcerative colitis: Cellulose nanofibers-enhanced delivery of 5-ASA and probiotics

Ulcerative colitis (UC) is a chronic inflammatory bowel disease initially treated with mesalazine (5-ASA). However, its effectiveness is limited by rapid absorption, low colonic concentration, and exacerbation of dysbiosis. Probiotics can mitigate dysbiosis if they survive the acidic conditions of the stomach. In this study, colon-specific microparticles (MPs) based on RS/P and reinforced with cellulose nanofibers (CNF) were used to co-encapsulate 5-ASA and L. rhamnosus. MPs prepared by spray-drying demonstrated a spherical shape, with sizes ranging from 1 to 10 μm, high encapsulation efficiency (up to 81.5 %), and maintenance of L. rhamnosus viability (5.74 log CFU/g of sample) even after 30 days of storage at 4 °C. Differential scanning calorimetry indicated a reduction in the melting peak of 5-ASA after microencapsulation, suggesting a decrease in its crystallinity. The samples also exhibited high mucoadhesivity, with the presence of CNF significantly increasing the speed of establishing interactions with mucin. In vitro release profiles showed lower release rates in acidic media, resulting in the majority of 5-ASA being released in intestinal and colonic media. These MPs represent a promising strategy for promoting specific release in the colon, minimizing side effects associated with conventional treatment, and potentially improving therapeutic efficacy in the context of UC.

Oral delivery of micro/nanoparticulate systems based on natural polysaccharides for intestinal diseases therapy: Challenges, advances and future perspectives

Colon-targeted oral delivery of drugs remains as an appealing and promising approach for the treatment of prevalent intestinal diseases (ID), such as inflammatory bowel disease (IBD) and colorectal cancer (CRC). Notwithstanding, there are numerous challenges to effective drug delivery to the colon, which requires the design of advanced strategies. Micro- and nanoparticles have received great attention as colon-targeted delivery platforms due to their reduced size and structural composition that favors the accumulation and/or residence time of drugs at the site of action and/or absorption, contributing to localized therapy. The choice by natural polysaccharides imparts key properties and advantages to the nano-in-microparticulate systems to effective colon-specific oral delivery. This review proposes to discuss the physiological barriers imposed by the gastrointestinal tract (GIT) against oral administration of drugs, as well as pathological factors and challenges of the ID for oral delivery of colon-targeted systems. We then provide an updated progress about polysaccharides-based colon-targeted drug delivery systems, including microparticulate, nanoparticulate and nano-in-microparticulate systems, highlighting their key properties, advantages and limitations to achieving targeted delivery and efficacious therapy within the colon. Lastly, we provide future perspectives, towards advances in the field and clinical translation of colon-targeted oral delivery systems for ID therapy.

QUOKKA, the pinhole small-angle neutron scattering instrument at the OPAL Research Reactor, Australia: design, performance, operation and scientific highlights

QUOKKA is a 40 m pinhole small-angle neutron scattering instrument in routine user operation at the OPAL research reactor at the Australian Nuclear Science and Technology Organisation. Operating with a neutron velocity selector enabling variable wavelength, QUOKKA has an adjustable collimation system providing source–sample distances of up to 20 m. Following the large-area sample position, a two-dimensional 1 m2position-sensitive detector measures neutrons scattered from the sample over a secondary flight path of up to 20 m. Also offering incident beam polarization and analysis capability as well as lens focusing optics, QUOKKA has been designed as a general purpose SANS instrument to conduct research across a broad range of scientific disciplines, from structural biology to magnetism. As it has recently generated its first 100 publications through serving the needs of the domestic and international user communities, it is timely to detail a description of its as-built design, performance and operation as well as its scientific highlights. Scientific examples presented here reflect the Australian context, as do the industrial applications, many combined with innovative and unique sample environments.

Resistant starch in food: a review

The nutritional property of starch is related to its rate and extent of digestion and absorption in the small intestine. For nutritional purposes, starch is classified as rapidly available, slowly available and resistant starch (RS). The exact underlying mechanism of relative resistance of starch granules is complicated because those factors are often interconnected. The content of RS in food is highly influenced by food preparation manner and processing techniques. Physical or chemical treatments also alter the level of RS in a food. Commercial preparations of RS are now available and can be added to foods as an ingredient for lowering the calorific value and improving textural and organoleptic characteristics along with increasing the amount of dietary fiber. RS has assumed great importance owing to its unique functional properties and health benefits. The beneficial effects of RS include glycemic control and control of fasting plasma triglyceride and cholesterol levels and absorption of minerals. This review attempts to analyze the information published, especially in the recent past, on classification, structure, properties, applications and health benefits of RS.

Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for 2009-2010

This review is the sixth update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2010. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, arrays and fragmentation are covered in the first part of the review and applications to various structural typed constitutes the remainder. The main groups of compound that are discussed in this section are oligo and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Many of these applications are presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis.