Lignin is identified as a promising candidate in renewable energy and bioproduct manufacturing due to its high abundance, polymeric structure, and biochemical properties of monomers. Thus, emerging opportunities exist in generating high-value small molecules from lignin through depolymerization. This review aims at providing an overview of the major technologies of lignin depolymerization. The feasibility of large-scale implementation of these technologies, including thermal, biological, and chemical depolymerizations, are discussed in relation to potential industrial applications. Lignin as a renewable alternative to petroleum-based chemicals has been well documented. This review attempts to emphasize potential applications of lignin-derived monomers and their derivatives as bioactives in food, natural health product, and pharmaceutical sectors. The critical review of the prospects and challenges of lignin-derived bioproducts reveals that the advancement of research and development is required to explore the applications of depolymerization of lignins to their full potential.

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This report presents a simple and inexpensive fabrication approach to a flexible transparent composite film as a "cut-and-paste" surface-enhanced Raman scattering (SERS) substrate for in situ detection of organic pollutants. First, a self-assembled monolayer of Ag-nanocubes (Ag-NCs) is obtained at the air/water interface. Then, the Ag-NC monolayer is retrieved onto a flexible transparent polyethylene (PE) film to achieve an Ag-NC@PE composite film as a flexible SERS substrate. As the Ag-NCs in the monolayer are closely and uniformly packed on the PE film, the Ag-NC@PE composite film shows high SERS-activity with good signal homogeneity and reproducibility. Furthermore, the flexible transparent Ag-NC@PE composite film is "cut into" small pieces and directly "pasted" onto contaminated fruits for in situ SERS detection, as a result 10 nM thiram, 1 μM 4-polychlorinated biphenyl and 10 nM methyl parathion contaminants on oranges are detected, respectively. Therefore the Ag-NC@PE composite film is an inexpensive and effective SERS substrate for rapid in situ detection of organic pollutants in aqueous solutions, on fruits and other solid objects.