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An efficient, one‐pot synthesis of 4‐substituted quinazoline derivatives via direct oxidative amination of C(sp3)–H bonds was demonstrated. The nature of the oxidant exhibited a considerable effect on the reaction, and tert‐butyl hydroperoxide in decane emerged as the best option. A variety of C1 sources could be used, affording 4‐substituted quinazolines in good yields. The three‐component reaction proceeded readily without any added catalyst, in which acetic acid from ammonium acetate was essential for the catalytic cycle. This protocol would offer a complementary pathway to previous methods in the synthesis of 4‐substituted quinazoline derivatives. [ABSTRACT FROM AUTHOR]

In 1984, biochemists George Glenner and Caine Wong, in search of ‘a unique amyloid fibril precursor protein in the serum’ of Alzheimer disease (AD) patients, successfully isolated and sequenced the first 24 amino acids of a ‘cerebrovascular amyloid fibril protein β’ that we now know as the amyloid-β (Aβ) peptide. This landmark paper laid the foundation for extensive research in the following decades that ultimately established the role of β-amyloidosis as a player in the pathogenesis of AD. [ABSTRACT FROM AUTHOR]

Due to its hydrophobicity and other unique physicochemical properties, graphene oxide (GO) has been extensively utilized in various biological applications. However, introducing nanomaterials into the biological environment may raise serious risk in terms of nanotoxicity, leading to some unintended changes to the structure and the function of other biomolecules. This study investigates the interaction of GO with the ubiquitin–proteasome system, one of the essential machineries in the cellular metabolism, using a combination of experimental and computational approaches. The experimental results show that GO could adsorb the 20S proteasome, causing a dose-dependent suppression of the proteolytic activity of proteasome. This adverse effect eventually disturbed other important cellular activities relevant to cell cycle and survival. Meanwhile, the molecular dynamics simulations revealed that when 20S proteasome was adsorbed onto the graphene surface, the central gate in the outer ring (α-subunit) for the entry and the exit of the peptide ligand to the protease active site was effectively blocked. These findings of GO induced functional disturbance of 20S proteasome provides a novel perspective to understand the molecular mechanism of GO’s cytotoxicity, which might further promote applications of GO in potential therapies for various cancers due to the abnormal elevation of the relevant proteasome activities. [ABSTRACT FROM AUTHOR]

Optimisation of conditions for gamma-valerolactone (GVL) pretreatment of Australian eucalyptus sawdust for high cellulose biomass and bioethanol production was demonstrated. Pretreatment parameters investigated included GVL concentrations of 35–50% w/w, temperatures of 120–180 °C and reaction durations of 0.5–2.0 h. Optimum conditions were determined using the response surface method (RSM) and central composite face-centred design. Cellulose content increased from 39.9% to a maximum of 89.3% w/w using treatments with 50% GVL at 156 °C for 0.5 h. Temperature had the most significant effect (RSM p < .05) on cellulose content of residual biomass and reducing operational duration of < 0.5 h may be viable according to RSM. PSSF fermentations of optimised pretreated eucalyptus sawdust produced up to 94% theoretical ethanol yield, which corresponded to approximately 181 kg of ethanol per dry ton of eucalyptus sawdust. The compositions of both the residual biomass and pretreatment liquors show that GVL pretreatment is a promising solvent for lignocellulosic biorefining. [ABSTRACT FROM AUTHOR]

Processing urban waste is becoming a major challenge, with the current state and forecasted increase in urbanisation. Finding novel approaches to reduce and recycle this waste, using value-adding applications, is paramount if we are to meet the needs of a growing population. Organic waste is of particular concern, as much of this can be treated and recycled for horticulture practices, but most find their final sink in landfill. With coffee now the second largest commodity worldwide, recycling these nutrient-rich by-products could reduce the amount of organic waste sent to landfill, whilst producing value adding products. Some chemical compounds present in these by-products, such as caffeine, tannins and chlorogenic acid are of ecotoxicological concern and can limit their value-adding applications. The aim of this literature review was to 1) characterise the waste obtained from the coffee industry; 2) outline the current value adding applications; 3) highlight limitations that prevent full utilization of coffee by-products and 4) discuss possible solutions that could maximize by-product utilization and ameliorating their negative environmental impacts. It was concluded that full utilization of these by-products is not always achieved, even though there is evidence to support their potential. This was mainly due to a lack of infrastructure and cross-chain networks between applications. [ABSTRACT FROM AUTHOR]

Momordica cochinchinensis (Cucurbitaceae) is the richest source of lycopene and β-carotene of all known fruits but the influences of collection sites, variety and environment on carotenoid accumulation is unknown. This study analysed the carotenoid content of 44 M. cochinchinensis aril samples collected from Australia, Thailand and Vietnam using HPLC, UV-visible spectrophotometry and compared with the colorimetry method. The highest lycopene content was observed in samples collected from Ha Noi (7.76 mg/g) of Northern Vietnam and Lam Ha (6.45 mg/g) and Lam Dong (6.64 mg/g) provinces of Central Vietnam. The highest β-carotene content was observed in a sample from Nam Dinh (9.60 mg/g) in Northern Vietnam while a variety from Hoa Binh province in Northern Vietnam had high contents of both lycopene (5.17 mg/g) and β-carotene (5.66 mg/g). Lycopene content was higher in samples collected from low temperatures (<14 °C) and higher elevations whilst β-carotene content was greatest at temperatures between 27 and 33 °C. Crop improvement for increased lycopene and β-carotene requires rapid and accurate methods of quantification. All three analytical methods utilised were in agreement for lycopene quantification. The ( a*/ b*) transformed colour value resulted in more linear relationship for lycopene indicating that colorimetry method could potentially be developed to select lycopene rich fruits in the field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Roles of oxidative stress on Age-related Macular Degeneration (AMD). • Plant carotenoids reduce AMD based on in vitro , in vivo and clinical trials. • Carotenoid benefits determined by treatment duration, body weight and exposure. Age-related macular degeneration (AMD) is a chronic disease leading to blindness in older adults and poses a significant economic burden to the healthcare system. The macula is regularly exposed to light, oxidative and inflammatory stress which play a central role in AMD pathogenesis. Lutein, zeaxanthin and their isomer meso -zeaxanthin are carotenoids from plants accumulating in the human macula that scavenge light, and reduce oxidation and inflammation. This review of relevant cellular, animal and human clinical trials investigated the benefits of the plant carotenoids, as a preventative and therapeutic treatment for AMD. Factors influencing the protective effects of the carotenoids were dependent on dose and treatment duration that could be important for translational applications leading to visual improvement in AMD patients. The application of carotenoid supplementation was discussed to provide non-invasive alternatives for the prevention and treatment of AMD. [ABSTRACT FROM AUTHOR]

The char yield from mycelium fungi can be improved via alkaline deacetylation wherein chitin polymer segments are converted to chitosan moieties. The influence of alkaline deacetylation conditions (e.g., temperature, incubation time and alkali concentration) on the biochemical composition, microstructural and physicochemical characteristics and thermal properties of mycelium fungi is poorly understood. In this paper, we investigated the influence of different alkaline deacetylation conditions on the degree of deacetylation and thermal properties of non-pathogenic Basidiomycota phylum, mycelium fungi, grown in molasses. Particularly, we determined the relationship between the degree of deacetylation and high-temperature char-forming characteristics of deacetylated mycelium. Further, the effect of an oxidizing agent, KMnO 4 , on the thermal stability and char-forming characteristics of alkaline-treated mycelium was investigated. This paper presents a comprehensive investigation of the relationship between the degree of deacetylation and char yields at high temperatures (e.g., >300°C) as well as an in-depth interrogation of the thermal degradation mechanisms governing the thermal stability of alkaline (and KMnO 4) treated mycelium. Research findings from this study have advanced knowledge of the development and design of bio-derived thermal protection materials for fire-threatened infrastructure. [Display omitted] [ABSTRACT FROM AUTHOR]