Application of aerosol-spray deposition for determination of fine structure of barley starch using atomic force microscopy

Sulfated Polysaccharides Derived from Hypnea valentiae and Their Potential of Antioxidant, Antimicrobial, and Anticoagulant Activities with In Silico Docking

Carrageenan, a sulfated polysaccharide, was produced by certain species of marine red seaweeds, which have been used as a significant source of food, feed, and antibiotic agent throughout history due to their alleged human health benefits. The present study aimed to derive the polysaccharides from Hypnea valentiae and describe the biological applications. Carrageenan was characterized by FT-IR, C-NMR, AFM, and their antimicrobial, antioxidant, and anticoagulant capabilities; furthermore, the larvicidal effect of methanol extract was generated from the seaweed against Aedes aegypti larvae at various concentrations. The molecular docking experiments were carried out computationally for finding the molecular insight of the macromolecules and small molecules' interaction using GLIDE docking by using Schrodinger software. Antibacterial zones of inhibition in different concentrations are compared with the 40 mg/mL higher activity against bacterial pathogens. Carrageenan is strong in all antioxidant activities, with the overall antioxidant (70.1 ± 0.61%) of radical at 250 μg/mL concentration being exhibited. The DPPH scavenging is effective in the inhibition of (65.74 ± 0.58%) radical at a concentration of 160 μg/mL and the hydroxyl scavenging (65.72 ± 0.60%) of activity at a concentration of 125 μg/mL being exhibited. Anticoagulant activities (APPT and PT) of carrageenan fraction were tested. H. valentiae and heparin sulphate shows higher activity of APTT (106.50 IU at 25 μg/mL) in comparison with the PT test (57.86 IU at 25 μg/mL) and the methanol extraction of higher larvicidal activity on A. aegypti (LC₅₀ = 99.675 μg/mL). In this study, the carrageenan was exploited through in vitro and in silico molecular docking studies against antimicrobial, antioxidant, and anticoagulant properties. The results were establishing the potentiality of the carrageenan which is an alternative source to control the mosquitocidal property in the future. Moreover, molecular docking of carrageenan against multiple targets results in −7 to −6 Kcal/mol binding score. Findings of carrageen from in vitro to in silico studies are needed for further validation of clinical pieces of evidence.

Barley grain constituents, starch composition, and structure affect starch in vitro enzymatic hydrolysis

The relationship between starch physical properties and enzymatic hydrolysis was determined using ten different hulless barley genotypes with variable carbohydrate composition. The ten barley genotypes included one normal starch (CDC McGwire), three increased amylose starches (SH99250, SH99073, and SB94893), and six waxy starches (CDC Alamo, CDC Fibar, CDC Candle, Waxy Betzes, CDC Rattan, and SB94912). Total starch concentration positively influenced thousand grain weight (TGW) (r(2) = 0.70, p < 0.05). Increase in grain protein concentration was not only related to total starch concentration (r(2) = -0.80, p < 0.01) but also affected enzymatic hydrolysis of pure starch (r(2) = -0.67, p < 0.01). However, an increase in amylopectin unit chain length between DP 12-18 (F-II) was detrimental to starch concentration (r(2) = 0.46, p < 0.01). Amylose concentration influenced granule size distribution with increased amylose genotypes showing highly reduced volume percentage of very small C-granules (<5 μm diameter) and significantly increased (r(2) = 0.83, p < 0.01) medium sized B granules (5-15 μm diameter). Amylose affected smaller (F-I) and larger (F-III) amylopectin chains in opposite ways. Increased amylose concentration positively influenced the F-III (DP 19-36) fraction of longer DP amylopectin chains (DP 19-36) which was associated with resistant starch (RS) in meal and pure starch samples. The rate of starch hydrolysis was high in pure starch samples as compared to meal samples. Enzymatic hydrolysis rate both in meal and pure starch samples followed the order waxy > normal > increased amylose. Rapidly digestible starch (RDS) increased with a decrease in amylose concentration. Atomic force microscopy (AFM) analysis revealed a higher polydispersity index of amylose in CDC McGwire and increased amylose genotypes which could contribute to their reduced enzymatic hydrolysis, compared to waxy starch genotypes. Increased β-glucan and dietary fiber concentration also reduced the enzymatic hydrolysis of meal samples. An average linkage cluster analysis dendrogram revealed that variation in amylose concentration significantly (p < 0.01) influenced resistant starch concentration in meal and pure starch samples. RS is also associated with B-type granules (5-15 μm) and the amylopectin F-III (19-36 DP) fraction. In conclusion, the results suggest that barley genotype SH99250 with less decrease in grain weight in comparison to that of other increased amylose genotypes (SH99073 and SH94893) could be a promising genotype to develop cultivars with increased amylose grain starch without compromising grain weight and yield.