5‐Hydroxymethylfurfural (HMF) is one of the versatile platform molecules that can be derived from biomass, and a promising starting substrate for producing 2,5‐diformylfuran (DFF) and 2,5‐furandicarboxylic acid (FDCA). DFF is a platform chemical with applications in pharmaceuticals, macrocyclic ligands, and functional polymeric materials. Importantly, FDCA is being considered as a potential alternative to replace terephthalic acid for producing the bioplastic polyethylene furanoate, instead of polyethylene terephthalate, by blending with ethylene glycol. A significant number of studies have focused on the oxidation of HMF to FDCA with metal‐containing heterogeneous catalysts in both aqueous and organic media in the presence of peroxides/air/molecular oxygen as the oxidant. In this regard, articles have recently been published related to HMF oxidation with base (nonprecious)‐metal‐containing catalysts that exhibit appealing activity towards DFF or FDCA in terms of yield. Thus, this Minireview focuses on recent developments in efficient transformations of HMF to DFF and FDCA with base‐metal‐containing heterogeneous catalysts in aqueous and organic media. This review further focuses on the direct transformation of glucose/fructose to DFF and/or FDCA with nonprecious‐metal‐containing catalysts in various solvents. Photocatalytic approaches for HMF oxidation with nonprecious metal‐ containing catalysts are also briefly discussed.

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Physical characteristics, amino acids composition, protein profiling, pasting characteristics, and phenolic compounds of brown rice (BR) and germinated brown rice (GBR) from different paddy cultivars (PB1, PS44, PB1509, PB1121, and PS5) were investigated. L* (lightness) decreased, but a* (redness and greenness) and b* (yellowness and blueness) increased with germination. Protein and ash content increased, whereas fat and amylose contents decreased with germination. GBR showed lower hardness and gumminess than BR. Foam stability and water absorption capacity from GBR flour were higher compared with BR flour. Accumulation of γ‐aminobutyric acid, histidine, arginine, proline, methionine, and acidic amino acids increased significantly with germination, and increase was related to change in accumulation of glutelin and prolamins. The accumulation of prolamins and glutelin acidic and basic subunits decreased with germination. GBR flour showed lower pasting viscosities compared with BR flour. Ferulic acid, p‐coumaric acid, and quercetin were present in both fractions of the bound form. GBR showed improved nutritional quality that varied in different cultivars. PB1121 was observed to be the best for producing GBR owing to greater changes brought in protein content, essential amino acids, catechin, chlorogenic acid, protocatechuic acid, vanillic acid, and foam stability.

The effects of transplantation date on milled rice (physicochemical, amino acids composition and protein profiling) of different cultivars and their starch characteristics (granules size distribution, pasting and thermal) were investigated. Head rice yield increased (2.0-4.1 %) and chalky grains (5-10 %) decreased with delaying the paddy transplantation of different cultivars by 20 days. Delayed transplantation of paddy significantly increased asparagine, glutamine, threonine, cysteine, methionine, tryptophan, lysine and proline content in milled rice. Early transplantation of paddy showed higher accumulation of glutelin and prolamines than that in milled rice from delayed transplantation. The change in amino acid composition of milled rice with delay in transplantation was related to variation in accumulation of glutelin and prolamines. Starch from delayed transplanted paddy showed higher peak viscosity and lower breakdown viscosity than those from early transplanted paddy. These differences were due to higher accumulation of amylose in starch from delayed transplanted paddy than that from early transplanted paddy due to exposure of former to lower night air temperature during starch synthesis.

A study was carried out to evaluate the potential of exogenously applied potassium nitrate [1.0 g·dm−3(K1), 2.5 g·dm−3(K2) and 5 g·dm−3(K3)] plus gibberellic acid (GA3) [0.005 g·dm−3(G1), 0.01 g·dm−3(G2) and 0.015 g·dm−3(G3)] on the growth and development of the cucumber (Cucumis sativusL.) ‘Seven Star F1’ during various growth stages (40, 55 and 70 days after sowing). Treatment of plants with K plus GA3stimulated growth shortened the fruit maturation period and increased quality compared with non-sprayed control. The combination G2K2resulted in maximum total yield, plant height, and total chlorophyll, phosphorus and nitrogen content in the leaves compared with other treatments. Fruit matured significantly earlier in plants sprayed with G2K2. Total yield and fruit quality dry matter, total suspended solids and antioxidant activity percentages were significantly higher in sprayed plants compared with controls. Potassium content in leaves and fruits reached the maximum level with G3K3treatment. The results clearly showed that the foliar application of G2K2proved to be the best choice for growing cucumber in terms of quantity and quality of yield.