Search

A close mimic of P680 and the TyrosineZ‐Histidine190 pair in photosystem II (PS II) has been synthesized using a ruthenium chromophore and imidazole‐phenol ligands. The intramolecular oxidation of the ligands by the photoproduced Ru(III) species is characterized by a small driving force, very similar to PS II where the complexity of kinetics was attributed to the reversibility of electron transfer steps. Laser flash photolysis revealed biphasic kinetics for ligand oxidation. The fast phase (τ<50 ns) corresponds to partial oxidation of the imidazole‐phenol ligand, proton transfer within the hydrogen bond, and formation of a neutral phenoxyl radical. The slow phase (5–9 μs) corresponds to full oxidation of the ligand which is kinetically controlled by deprotonation of the distant 1‐nitrogen of the imidazolium. These results show that imidazole with its two protonatable sites plays a special role as a proton relay in a 'proton domino' reaction. [ABSTRACT FROM AUTHOR]

Ruthenium tris-bipyridine derived complexes functionalized by either carboxyl or phosphonyl groups were tested as sensitizers for the photocatalytic reduction of carbon dioxide in the presence of nickel cyclam acting as a catalyst, and a sacrificial donor. These systems were shown to be as efficient as the unsubstituted compounds in solution. Covalent binding to titania nanoparticles gave slightly different results from those with the untreated semiconductor.

Click chemistry was used to assemble a trimetallic RuII-NiII-RuII complex made up of two tris(bipyridyl)ruthenium(II)-based photosensitisers and a nickel(II)-salen complex. The electrochemical and photophysical properties of the resulting photosensitiser-metal complex are discussed. Photoinduced activation triggered by visible light absorption induces a fast intramolecular charge shift from one of the chromophores to the salen cavity to generate a nickel(III)-salen species. [ABSTRACT FROM AUTHOR]

SUMMARY Non‐coding RNAs play crucial roles in plant responses to viral stresses. However, their molecular mechanisms in tea leaf spot responses remain unclear. In this study, using Camellia sinensis, we identified lncRNA81246 as a long non‐coding RNA that localizes to both the nucleus and cytoplasm. It functions as a competitive endogenous RNA, thereby disrupting CsNAC1 (encoding NAC domain‐containing protein 1) degradation mediated by miR164d. Silencing lncRNA81246 increased the resistance of tea plants to presistanceathogens, whereas transient lncRNA81246‐overexpression plants showed decreased resistance to pathogens. Co‐expression assays in Nicotiana benthamiana revealed that lncRNA81246 affects the miR164d–CsNAC1 regulatory module. Transient miR164d‐overexpression and silencing assays demonstrated its positive regulation of tea plant resistance. Specifically, silencing its target, CsNAC1,enhanced disease resistance, whereas transient overexpression reduced plant resistance. Yeast one‐hybrid, dual‐luciferase, and RT‐qPCR assay results suggested that CsNAC1 alters the expression of CsEXLB1, whereas AsODN and tobacco transient overexpression assays showed that CsEXLB1 negatively regulated tea plant resistance. Thus, our research demonstrated that lncRNA81246 acts as a mediator to interfere with the miR164d–CsNAC1 regulatory module involved in the disease resistance of tea plants. [ABSTRACT FROM AUTHOR]

Lipid composition, physicochemical, antioxidant, and thermal properties of gurum seed oil obtained from supercritical CO2, screw pressing and hexane extraction were studied. Results showed that the highest yield of lipids was obtained by the hexane extraction (34.04%) as compared to supercritical CO2 (30.05%) and screw pressing (27.5%), respectively. The physicochemical properties of oil extracted by different methods are important criteria to select the oil for edible purpose. Supercritical CO2 gurum oil has higher linoleic acid composition in comparison to the screw press gurum oil and hexane gurum oil. Supercritical CO2 gurum oil and hexane gurum oil showed lower free fatty acid values (0.60 and 0.46%, respectively). Supercritical CO2 gurum oil has shown higher amounts of (C18:1‐C18:1‐C18:2)‐TAG. Supercritical CO2 gurum oil has excellent properties, especially in the terms of polyphenol, β‐tocopherol, ergosta‐7, 22‐dein‐3‐ol, and antioxidant activity. Thus, suggesting the supercritical CO2 gurum oil as desired alternative for extracting fats with altitude nutritional value, while keeping bioactive compounds intact. Practical applications: This study is beneficial for extraction of oil from seeds. Supercritical CO2 fluid extraction (SFE) is quite demanding technique on the industrial scale. SFE is a novel method to extract the oil from gurum seed and can be used in various fields such as food and pharmaceutical industries. The presented results revealed that gurum seed oil extracted by SFE could be the desired alternative for extracting fats with altitude nutritional values while keeping intact healthier bioactive compounds for wellbeing of human health. [ABSTRACT FROM AUTHOR]

Seeds from the cucurbitaceae plant family are discarded as the byproducts which generally obtained after extraction of oil during food processing. Recently, found a great deal of interest as cucurbit seeds are found to be rich source of nutrients such as monounsaturated fatty acids, polyunsaturated fatty acids, tocopherols (α‐Tocopherol, β‐Tocopherol, δ‐Tocopherol, γ‐Tocopherol), carotenoids, β‐carotene, phytosterol, proteins, minerals, vitamins, phenolic compounds, and antioxidants. Despite the potential nutritional benefits, the commercial product of cucurbit plants are lacking in the market. Therefore, there is an urgent need to increase production and utilization of cucurbit seed oil for human nutrition. The main purpose of the present review is to sum up the published information on the nutritional potential of cucurbit seed oils to promote industrial production and stimulates further research on commercial use of cucurbit seeds. Practical applications: The aims of this review are to highlight the nutritional values and antioxidant properties of cucurbit seed and their impact on the overall human health. These cucurbit seeds are rich source of vitamins and minerals which are necessary for healthy human diet. In addition to other commercial oils, cucurbits oils are equally important and rich in essential active ingredients. Quite abundance of cucurbit seeds in African continents can pave way to enhance production on the industrial scale which can create employability ranging from farmers to skilled workers. In all, the oil produced from the cucurbit seeds can be applied practically to implement large‐scale production as a part of food industry and dietary supplement industry in paramedical sector. Seeds from the cucurbitaceae plant family are generally discarded as a waste product. The cucurbit seeds are found to be rich in nutrients such as monounsaturated fatty acids, polyunsaturated fatty acids, tocopherols. Therefore these seeds are studied in details to know it's nutritional and antioxidant properties. Although rich source of vitamins and minerals cucurbit seeds are not yet used on the commercial scale for oil production. This review has discussed in depth the properties of cucurbit seeds and their beneficial health effect on human body. In near future several industries, not only limited to food but also pharmaceuticals, will utilize these seeds as a raw material leading to mass production of oils and dietary supplements. [ABSTRACT FROM AUTHOR]

Carvacrol expresses a wide range of biological activities, but the studies of its mechanisms focused on bacteria, mainly involving the destruction of the plasma membrane. In this study, carvacrol exhibited strong activities against several phytopathogenic fungi and demonstrated a novel antifungal mechanism against Lasiodiplodia theobromae. RNA sequencing indicated that many genes of L. theobromae hyphae were predominately induced by carvacrol, particularly those involved in replication and transcription. Hyperchromic, hypsochromic, and bathochromic effects in the UV-visible absorption spectrum were observed following titration of calf thymus DNA (ctDNA) and carvacrol, which indicated the formation of a DNA–carvacrol complex. Circular dichroism (CD) spectroscopy indicated that the response of DNA to carvacrol was similar to that of 4′,6-diamidino-2-phenylindole (DAPI) but different from that of ethidium bromide (EB), implying the ionic bonds between carvacrol and ctDNA. Fluorescence spectrum (FS) analysis indicated that carvacrol quenched the fluorescence of double-stranded DNA (dsDNA) more than single-stranded DNA, indicating that carvacrol mainly bound to dsDNA. A displacement assay showed that carvacrol reduced the fluorescence intensity of the DNA–DAPI complex through competition with DAPI, but this did not occur for DNA–EB. The FS assay revealed that carvacrol bound to the AAA sequence on the minor groove of ds-oligonucleotides. The hydroxyl of carvacrol was verified to bind to ctDNA through a comparative test in which structural analogs of carvacrol, including thymol and 4-ethyl-1,2-dimethyl, were analyzed. The current study indicated carvacrol can destruct plasma membranes and bind to the minor groove of DNA, inhibiting fungal proliferation by disturbing the stability of dsDNA. [ABSTRACT FROM AUTHOR]