Fine Structures of Amylose and Amylopectin from Large,Medium, and Small Waxy Barley Starch Granules

Amylose and amylopectin were prepared from large, medium, and small granule starches of classified waxy barley flour, and their fine structures were investigated. The amylose content had a wide distribution range (≈1.4–9.4%). Number‐average degrees of polymerization (DP_n) of the amyloses were similar among the samples (≈1,200–1,300). But number of chains per molecule (NC) decreased from the surface to the center (≈6–10 chains). DP_n of the amylopectins varied from 4,657 to 14,604; decreased in the order of large, medium, and small granules in same fractions of the grain; and increased from the surface layer to the center. Longest chains (LC) were not found in any of the amylopectin molecules. The large amylopectin molecule had more long chains and fewer A chains than the small molecule. The amylose content had definite effects on the transition temperature range and crystal formation of the starch granules. There were positive correlations between DP_n of the amylopectin and relative crystallinity (γ = +0.69) and enthalpy value (γ = +0.80), respectively. These findings may help to elucidate biosynthesis mechanism of starch.     

A global systematic literature review on sustainable soil management practices (1994–2022)

Sustainable Soil Management Practices (SSMP) offer potential benefits while conserving natural resources. However, the low adoption of SSMP limits the achievement of their full potential. To examine the current state of knowledge on SSMP adoption and identify research gaps, we systematically reviewed 269 peer-reviewed publications pooled from Scopus, Web of Science and ScienceDirect, covering the period from 1994 to 2022. We assessed the temporal and spatial transitions of SSMP adoption and identified a broad perspective of 14 themes on SSMP adoption and highlight the research trends and gaps. Prior to 2010, research on SSMP adoption was concentrated on a few themes and has become diversified in later years, covering emerging themes such as climate change and use Information and Communication Technology (ICT). Publications on SSMP adoption exhibited a global distribution, with particular emphasis on the African continent due to the flow of donors' funds driven by severe soil degradation and limited use of improved technologies in Africa. Studies on minimum soil disturbance were prevalent worldwide, with the highest number of publications. Our findings also indicate a strong research collaboration between developed and developing countries, showcasing donor-driven collaborative efforts and mutual benefits across different regions. This review however highlights the limited inclusion of local knowledge in SSMP promotion and recommends a bottom-up approach for future initiatives. In the discussion section, different critical factors of SSMP adoption covering farmers' perceptions, climate change, policy impact and the use of ICT are discussed. These findings and identified research gaps are useful for further research and the development of sustainable soil management policies, programmes and projects.