Regulation of a gene encoding coniferaldehyde 5-hydroxylase leads to substantial alterations in lignin structure in rice cell walls, identifying a promising genetic engineering target for improving grass biomass utilization. The aromatic composition of lignin greatly affects utilization characteristics of lignocellulosic biomass and, therefore, has been one of the primary targets of cell wall engineering studies. Limited information is, however, available regarding lignin modifications in monocotyledonous grasses, despite the fact that grass lignocelluloses have a great potential for feedstocks of biofuel production and various biorefinery applications. Here, we report that manipulation of a gene encoding coniferaldehyde 5-hydroxylase (CAld5H, or ferulate 5-hydroxylase, F5H) leads to substantial alterations in syringyl (S)/guaiacyl (G) lignin aromatic composition in rice (Oryza sativa), a major model grass and commercially important crop. Among three CAld5H genes identified in rice, OsCAld5H1 (CYP84A5) appeared to be predominantly expressed in lignin-producing rice vegetative tissues. Down-regulation of OsCAld5H1 produced altered lignins largely enriched in G units, whereas up-regulation of OsCAld5H1 resulted in lignins enriched in S units, as revealed by a series of wet-chemical and NMR structural analyses. Our data collectively demonstrate that OsCAld5H1 expression is a major factor controlling S/G lignin composition in rice cell walls. Given that S/G lignin composition affects various biomass properties, we contemplate that manipulation of CAld5H gene expression represents a promising strategy to upgrade grass biomass for biorefinery applications.

As a promising optical method used in a variety of applications surface plasmon resonance (SPR) sensors are employed over a wide range of boundaries. This research proposes a highly sensitive SPR based sensor with a novel hybrid structure using transition metal dichalcogenides (e.g. WSe2, PtSe2) along with black phosphorene (BP) through comprehensive numerical study. To analyze and evaluate the performances of the proposed sensor, the widely used transfer matrix method (TMM) was used. The performances of the sensor were measured in terms of reflectivity, sensitivity, detection accuracy (DA), and figure of merit (FOM). The sensor structure was optimized by changing different structural parameters of the hybrid architecture to obtain better performances. The results revealed that insertion of PtSe2 with WSe2 and BP over a gold layer of the conventional structure improved the performance of the sensor and the maximum sensitivity of the sensor was measured as 200 deg/RIU with a FOM of 17.70 RIU -1 . As well, the light penetration through the optimized sensor is investigated using the finite element method (FEM) based software. With this kind of high sensing capabilities, it may be convinced that the proposed sensor can be applied in different fields of biosensing to detect liquid biological and biochemical samples or analytes.

Highlights  Cd-Zn sulphide films synthesized via chemical bath deposition technique were investigated for photovoltaic and optoelectronic applications.  XRD studies show that Cd-Zn sulphide films are composed of nanocrystalline structure surrounded by the amorphous grain boundaries.  Nanocrystalline structures of the films were confirmed by the SEM.  The band gap of these films is a combination of composition and size  EU and σ studies ascribed the shrinkage of the solar absorption edges around the optical band-gaps.