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•Naturally derived compounds provide a potential wealth of antiviral agents.•We reviewed the literature on phytochemicals against different human and animal coronaviruses.•Compounds ...showing the greatest potential for drug development are highlighted.•All promising compounds contain a conjugated ring structure.•Most are polyphenols and/or contain a substituted fused ring.
Coronaviruses are responsible for a growing economic, social and mortality burden, as the causative agent of diseases such as severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), avian infectious bronchitis virus (IBV) and COVID-19. However, there is a lack of effective antiviral agents for many coronavirus strains. Naturally existing compounds provide a wealth of chemical diversity, including antiviral activity, and thus may have utility as therapeutic agents against coronaviral infections. The PubMed database was searched for papers including the keywords coronavirus, SARS or MERS, as well as traditional medicine, herbal, remedy or plants, with 55 primary research articles identified. The overwhelming majority of publications focussed on polar compounds. Compounds that show promise for the inhibition of coronavirus in humans include scutellarein, silvestrol, tryptanthrin, saikosaponin B2, quercetin, myricetin, caffeic acid, psoralidin, isobavachalcone, and lectins such as griffithsin. Other compounds such as lycorine may be suitable if a therapeutic level of antiviral activity can be achieved without exceeding toxic plasma concentrations. It was noted that the most promising small molecules identified as coronavirus inhibitors contained a conjugated fused ring structure with the majority being classified as being polyphenols.
Applications of near-infrared spectroscopy for measuring various aspects of grain quality have expanded rapidly in recent years. One application that could be of particular use to growers and ...industry is the detection of insect pests across a range of stored grains. This prospect was first reported over 20 years ago, but the accuracy of this technique does not currently meet FDA standards for the quantification of insect fragments in bulk wheat and flour samples. When considering bulk samples, near-infrared spectroscopy may be suitable for identifying the presence of infestation in samples, followed by flotation testing to provide an accurate quantitative value. Much higher accuracy has been found for the detection of pest species at the single-kernel level. With faster spectrophotometers and kernel sorting systems, single-kernel analysis is likely to be utilised more in the future and could even render bulk analysis of samples redundant. This technology could allow for the detection and identification of pest species in every single kernel of a representative grain sample. The development and application of more sensitive spectrophotometers, such as FT-NIR (Fourier transform near infrared) and more powerful chemometric data analysis techniques are also likely to provide significant improvements, through allowing the minute chemical differences present in bulk infested grains to be accurately detected and quantified.
•NIRS shows good accuracy for detecting insect infestations in individual grains.•Poorer accuracy is found at detecting infestations in bulk samples.•Rapid single kernel characterisation systems may render bulk analysis redundant.•New developments include hyperspectral imaging, FT-NIR and improved data analysis.
Infrared spectroscopy (wavelengths ranging from 750-25,000 nm) offers a rapid means of assessing the chemical composition of a wide range of sample types, both for qualitative and quantitative ...analyses. Its use in the food industry has increased significantly over the past five decades and it is now an accepted analytical technique for the routine analysis of certain analytes. Furthermore, it is commonly used for routine screening and quality control purposes in numerous industry settings, albeit not typically for the analysis of bioactive compounds. Using the Scopus database, a systematic search of literature of the five years between 2016 and 2020 identified 45 studies using near-infrared and 17 studies using mid-infrared spectroscopy for the quantification of bioactive compounds in food products. The most common bioactive compounds assessed were polyphenols, anthocyanins, carotenoids and ascorbic acid. Numerous factors affect the accuracy of the developed model, including the analyte class and concentration, matrix type, instrument geometry, wavelength selection and spectral processing/pre-processing methods. Additionally, only a few studies were validated on independently sourced samples. Nevertheless, the results demonstrate some promise of infrared spectroscopy for the rapid estimation of a wide range of bioactive compounds in food matrices.
Near-infrared spectroscopy (NIRS) is a rapid, noninvasive and cheap method of profiling the chemical composition of a broad range of sample types. Over the past two decades, it has been used in ...numerous entomological applications, ranging from taxonomy and metabolomic profiling to the prediction of insect age and sex. This review provides a perspective on the historical and contemporary applications of NIRS for entomology. Two areas that show particular promise are the detection and identification of insects infesting stored food products, and the rapid, low-cost and non-lethal profiling of cuticular hydrocarbons of individual insects.
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•Behavioural lateralization has not been investigated in Iridomyrmex purpureus.•No evidence of lateralization in passing side following antennation.•However, non-random turning ...behaviour prevented collision in 93% of cases.•This appears to be in response to the other ant’s movement, rather than in-built lateral bias.
Although handedness was previously believed to be rare amongst insects, recent research has suggested strong evidence for behavioural lateralization across several ant species. This study investigated whether workers of the southern meat ant (Iridomyrmex purpureus) showed behavioural lateralization while passing other workers along a trail, after they stop to engage in antennation. Analysis of 275 interactions demonstrated that I. purpureus individuals show non-random turning behaviour following antennation, which helps them avoid subsequent collision in the majority (93%) of cases. Furthermore, their efficiency in passing one another following antennation is only 19% slower compared to the optimal scenario. The non-random turning behaviour does not appear to be due to in-built lateral bias or other factors such as approach angle, but rather in response to the movements of the ant which they are passing.
Chocolate-coated confectionery, including fruits and nuts, is an increasingly popular snack food. Non-destructive discrimination of the core composition could be useful for quality assurance ...purposes, such as ensuring the absence of peanuts in a batch of chocolate-coated sultanas. This study investigated the optimum pre-processing methods and discrimination algorithms for identifying chocolate-coated peanuts and sultanas from their near-infrared (NIR) spectra. The best-performing results were found using partial least squares discriminant analysis (PLS-DA) and principal component analysis with linear discriminant analysis (PCA-LDA), which both demonstrated 100% classification accuracy when applied to the validation set. Principal component analysis with support vector machine (PCA-SVM) showed slightly poorer results, particularly when using non-optimal pre-processing techniques. In general, the most accurate results were found when using either the unprocessed or SNV-processed spectral data. This work supports the prospect of using near-infrared spectroscopy for the quality assurance in the manufacture or wholesale of panned chocolate goods.
•A review of Alzheimer’s disease pathophysiology focused on oxidative stress.•Plant derived antioxidants show potential as novel adjuvant therapeutics.•Combination natural polyphenolics and ...pharmaceuticals may provide synergistic benefits.•Future in vitro and in vivo studies needed to investigate biochemistry and mechanism of action of polyphenolics.•Clinical trials required to determine efficacy of polyphenolic antioxidant agents.
The aim of this research was to review the literature on Alzheimer’s disease (AD) with a focus on polyphenolics as antioxidant therapeutics.
This review included a search of the literature up to and including September 2019 in PubMed and MEDLINE databases using search terms that included: Alzheimer’s Disease, Aβ peptide, tau, oxidative stress, redox, oxidation, therapeutic, antioxidant, natural therapy, polyphenol. Any review articles, case studies, research reports and articles in English were identified and subsequently interrogated. Citations within relevant articles were also examined for consideration in this review.
Alzheimer’s disease is a neurodegenerative disorder that is clinically characterised by the progressive deterioration of cognitive functions and drastic changes in behaviour and personality. Due to the significant presence of oxidative damage associated with abnormal Aβ accumulation and neurofibrillary tangle deposition in AD patients’ brains, antioxidant drug therapy has been investigated as potential AD treatment. In particular, naturally occurring compounds, such as plant polyphenols, have been suggested to have potential neuroprotective effects against AD due to their diverse array of physiological actions, which includes potent antioxidant effects.
The impact of oxidative stress and various mechanisms of pathogenesis in AD pathophysiology was demonstrated along with the therapeutic potential of emergent antioxidant drugs to address such mechanism of oxidation.
This proof-of-concept study aimed to investigate the potential of using near infrared (NIR) spectroscopy to discriminate between genera of Gonipterini weevil. NIR spectra (10,000–4,000 cm−1) were ...collected from 15 Gonipterini specimens, comprising three genera and five species. Principal component analysis (PCA) highlighted the inter-specific variation in NIR spectra, with separation observed between most species across the first two principal components. Partial least squares discriminant analysis (PLS-DA) could be used to differentiate between the genera (78% accuracy), although support vector machine (SVM) modelling gave improved accuracy (91%). The results support the prospect of NIR spectroscopy for the rapid discrimination between Gonipterini genera.
Non-destructively identifying the centre composition of panned chocolate goods may be useful in quality assurance settings. However, no studies to date have investigated this topic. In this study, ...near infrared spectra (1000–2500 nm) were collected from chocolate-coated peanuts and chocolate-coated sultanas (n = 170 of each) in order to investigate the prospect of non-invasively detecting the composition of the centre. Principal component analysis confirmed that the spectra of these samples were distinct from one another. The partial least squares discriminant analysis (PLS-DA) model showed a high level of separation between chocolate-coated peanuts and sultanas in the training set (R2 = 0.95; RPD = 4.4). Discrimination between peanut and sultana samples from an independent test set was also possible, although with slightly less distinct separation between the sample types. A soft independent modelling by class analogy model was also able to differentiate between the two sample types, albeit with higher levels of misclassification compared to PLS-DA. Incorporating samples from different manufacturers may be useful for improving the broader applicability of the model.
Leaf water content (LWC) is a crucial physiological parameter that plays a limiting role in the efficiency of photosynthesis and biomass production in many plants. This study investigated the use of ...diffuse reflectance near-infrared spectroscopy (NIRS) for the rapid prediction of the gravimetric LWC in eucalypt leaves from Eucalyptus and Corymbia genera. The best-performing model for LWC gave a R2pred of 0.85 and RMSEP of 2.32% for an independent test set, indicating that the handheld NIR instrument could predict the LWC with a high level of accuracy. The use of support vector regression gave slightly more accurate results compared with partial least squares regression. Prediction models were also developed for leaf thickness, although these were somewhat less accurate (R2pred of 0.58; RMSEP of 2.7 µm). Nevertheless, the results suggest that handheld NIR instruments may be useful for in-field screening of LWC and leaf thickness in Australian eucalypt species. As an example of its use, the NIR method was applied for rapid analysis of the LWC and leaf thickness of every leaf found on an E. populnea sapling.
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