Host genotype and gender are among the factors that influence the composition of gut microbiota. We studied the population structure of gut microbiota in two lines of chickens maintained under the same husbandry and dietary regimes. The lines, which originated from a common founder population, had undergone 54 generations of selection for high (HW) or low (LW) 56-day body weight, and now differ by more than 10-fold in body weight at selection age. Of 190 microbiome species, 68 were affected by genotype (line), gender, and genotype by gender interactions. Fifteen of the 68 species belong to Lactobacillus. Species affected by genotype, gender, and the genotype by gender interaction, were 29, 48, and 12, respectively. Species affected by gender were 30 and 17 in the HW and LW lines, respectively. Thus, under a common diet and husbandry host quantitative genotype and gender influenced gut microbiota composite.

This study examines a novel polyelectrolyte-macroion complex (PMC) between chitosan, a cationic polysaccharide, and cellulose nanocrystals (CNCs), anionic, cylindrical nanoparticles, for potential applications in drug delivery. CNCs were prepared by H(2)SO(4) hydrolysis of wood pulp. The formation of PMCs was monitored by turbidimetric titration. In titrations of a chitosan solution with a CNC suspension, the turbidity reached a plateau, but it had a maximum and then decreased when the direction of titration was reversed. PMC particles were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, dynamic light scattering, and laser Doppler electrophoresis. The particles were composed primarily of CNCs and ranged in size from a few hundred nanometers to several micrometers, depending on the cellulose/chitosan ratio. Particles formed at amino/sulfate group molar ratios>1 were nearly spherical in shape and positively charged, whereas particles formed at ratios <1 had well-defined nonspherical shapes and were negatively charged.

This study examines the effects of pH and salt concentration on the formation and properties of chitosan− cellulose nanocrystal (CNC) polyelectrolyte−macroion complexes (PMCs). The components' pK values, determined by potentiometric titration, were 6.40 for chitosan and 2.46 for the CNCs. The turbidity of PMC particle suspensions was measured as a function of chitosan−CNC ratio, pH, and salt concentration. The maximum turbidity values in titrations of a chitosan solution with a CNC suspension and vice versa occurred at charge ratios of 0.47 ± 0.11 (SO 3 − /NH 3 + ) and 1.16 ± 0.06 (NH 3 + /SO 3 − ), respectively. A pH increase caused a turbidity decrease due to shrinking of the PMC particles upon changes in their components' degrees of ionization. An increase in salt concentration caused a decrease in turbidity due to charge-screening-related shrinking of the PMC particles. The effects of pH and salt concentration on particle size were confirmed by scanning electron microscopy.

No abstract

This study investigated the effects of different rates of nanochitin in soil on the grain yield and quality of winter wheat. Nanochitin obtained by acidic hydrolysis of shrimp chitin was a rod-like whisker possessing a hydrodynamic diameter of 143 nm and ζ potential of 55.7 mV. Two varieties of winter wheat, multi-spike wheat (MSW) and large spike wheat (LSW), were treated with the nanochitin suspension in outside pot experiments. The results showed that 0.006 g kg of nanochitin in soil could significantly enhance the yield by 23.0% for MSW and 33.4% for LSW, with significant increases of net photosynthesis rate, stomatal conductance, intercellular CO concentrations, and transpiration rate in flag leaf at the grain filling stage. Grain protein, iron, and zinc contents in wheat treated with nanochitin were also increased by 5.0, 10.3, and 22.1% for MSW and 33.4, 32.0, and 27.0% for LSW, respectively. This indicated that utilization of nanochitin has a great potential in future agriculture sustainability and crop production.