Reflux Extraction Optimization and Antioxidant Activity of Phenolic Compounds from Pleioblastus amarus (Keng) Shell

Phenols were extracted from the Pleioblastus amarus (Keng) shell (PAS) using ethanol. A Plackett–Burman assessment indicated that the factors affecting polyphenol extraction included the ethanol concentration, extraction temperature, liquid to solid ratio, extraction time, and reflux extraction times; the best extraction parameters were the ethanol concentration of 75%, a 20:1 liquid to solid ratio, and an extraction time of 2.1 h. The number of polyphenols was 7.216 mg/g. Furthermore, the phenol composition analysis showed the presence of p-Coumaric acid (196.88 mg /mL) and rutin (312.9 mg /mL), which were used for the in vitro extraction and determination of the antioxidant activity. According to the A, B, C, and D antioxidant activity assays, the ethyl acetate phase was the strongest with low IC50 values of 0.169 ± 0.01 mg/mL, 0.289 ± 0.01 mg/mL, 0.372 ± 0.01 mg/mL, and 1.029 ± 0.03 mg/mL, respectively, confirming high antioxidant activity. For the n-butanol and petroleum ether phases, antioxidant activity was lower. This study showed that the polyphenol extract from Pleioblastus amarus (Keng) shell displayed excellent antioxidant activity, enhancing its practical application.

Potential Use of Annona Genus Plants Leaf Extracts to Produce Bioactive Transdermal Patches by Supercritical Solvent Impregnation

The objective of the present work was to develop a bioactive transdermal patch functionalized with Annona leaf extracts (ALE) by means of supercritical impregnation technique. The potential of six different Annona leaf extracts (ALE) obtained with the enhanced solvent system formed by carbon dioxide + ethanol/acetone was evaluated taking into account the antioxidant activity, total phenol composition and global extraction yields. For the impregnation of ALE, two drug supporting systems were tested: hydrocolloid sodium carboxymethyl cellulose (NaCMC) and polyester dressings (PD). The effect of the impregnation conditions, including pressure (P), temperature (T), percent of co-solvent (ethanol) and ALE/polymer mass ratio, was determined with regard to the loading and the functional activity of the impregnated samples. The optimal impregnation conditions of ALE were established at 55 °C and 300 bar which led to obtained transdermal patches with antioxidant and antimicrobial capacity. In order to understand the behavior of the process, the homogeneity of the samples in the vessels was also evaluated. The best results were obtained at higher proportions of co-solvent in the system.

The Potential of Virgin Olive Oil from cv. Chondrolia Chalkidikis and Chalkidiki (Greece) to Bear Health Claims according to the European Legislation

The European food legislation authorizes the use of certain health claims based on a scientific basis. This study aimed to evaluate the fatty acid, tocopherol, and polar phenol composition of virgin olive oil (VOO) from cv. Chondrolia Chalkidikis and Chalkidiki regarding the fulfillment of official requirements for the health claims of ‘oleic acid’, ‘vitamin E’, and ‘olive oil polyphenols’. The examination of representative industrial VOOs from 15 olive mills of the Chalkidiki regional unit showed that the two cultivars yield oils contained the necessary concentrations of the responsible bioactive compounds. This evidence was further substantiated by a four harvest study whereby olives from different maturity stages were sampled from three olive groves. Oils were extracted at a laboratory scale and examined for their content in the above-mentioned three categories of constituents. Oils produced at industrial scale from olives harvested on the ‘technological optimum’ stage according to the olive grove proprietor were also analyzed. Extra virgin olive oil of the studied cultivars can safely bear the generic claims for ‘oleic acid’ and ‘vitamin E’. The cultivars present great potential regarding the total hydroxytyrosol and tyrosol content of the extracted oil required to attain the third health claim that may be influenced negatively by manufacturing practices.

Antioxidant and Neuroprotective Activity of Extra Virgin Olive Oil Extracts Obtained from Quercetano Cultivar Trees Grown in Different Areas of the Tuscany Region (Italy)

Neurodegenerative diseases are driven by several mechanisms such as inflammation, abnormal protein aggregation, excitotoxicity, mitochondrial dysfunction and oxidative stress. So far, no therapeutic strategies are available for neurodegenerative diseases and in recent years the research is focusing on bioactive molecules present in food. In particular, extra-virgin olive oil (EVOO) phenols have been associated to neuroprotection. In this study, we investigated the potential antioxidant and neuroprotective activity of two different EVOO extracts obtained from Quercetano cultivar trees grown in two different areas (plain and hill) of the Tuscany region (Italy). The different geographical origin of the orchards influenced phenol composition. Plain extract presented a higher content of phenyl ethyl alcohols, cinnammic acids, oleacein, oleocanthal and flavones; meanwhile, hill extract was richer in lignans. Hill extract was more effective in protecting differentiated SH-SY5Y cells from peroxide stress thanks to a marked upregulation of the antioxidant enzymes heme oxygenase 1, NADPH quinone oxidoreductase 1, thioredoxin Reductase 1 and glutathione reductase. Proteomic analysis revealed that hill extract plays a role in the regulation of proteins involved in neuronal plasticity and activation of neurotrophic factors such as BDNF. In conclusion, these data demonstrate that EVOOs can have important neuroprotective activities, but these effects are strictly related to their specific phenol composition.

Phenol Contents and Antioxidant Activity of Sonokeling (Dalbergia latifolia Roxb) Wood

Dalbergia latifolia or sonokeling is a native species of Java, Indonesia, used as an important wood for furniture and building materials, due to the high of durability and beautiful color. This study, therefore, aim to investigate the phenol composition, represented by total phenolic, flavonoid, and flavanol content, as well as antioxidant activity, conducted by DPPH (1, 1-diphenyl-2-picrylhydrazyl) method on Dalbergia latifolia wood. The sample was extracted using ethanol-toluene solvent in a Soxhlet apparatus, and subsequently subjected to column chromatography. This treatment yielded 12 fractions, which were then evaluated for phenol contents and antioxidant activity. The results showed a high antioxidant activity and total phenolic content in Fr.1- Fr.3, while latifolin was detected and characterized by GC-MS and a literature comparison. Therefore, it was established that the antioxidant activity of D. latifolia wood extractives properly correlated with the total phenolic, but not with the total flavonoid and flavanol contents.

Bioactive compounds content of Snake Fruit Peel, Aloe Vera, and Stevia Extracts as Raw Material of Functional Drinks

The objective of the research is to analyze the content of the bioactive compounds of extracts made of snake fruit skin, Aloe vera, and Stevia as materials to make functional drinks. Salacca zalacca (Gaert.) Voss. cultivar has flavonoid, tannin, and a bit of alkaloid on its fruit peel. Aloe vera and Stevia also known to have antioxidant compounds. Aloe vera controls the metabolism of carbohydrates and maintaining homeostasis of glucose. The research methods are divided into steps: 1) the extraction of Snake fruit peel, Aloe vera, and Stevia; 2) the formulation of the functional drink; 3)the evaluation of antioxidant, total phenol, and tannin levels of the formulated extracts. The research used Randomized Group Design (RGD) of two factors, and each factor consists of 4 levels and 2 levels. Factor I=the ratio of snake fruit peel:Aloe vera extract (10:90 (v/v); 30:70 (v/v); 70:30 (v/v); 90:10 (v/v)) and factor II= addition of Stevia filtrate (2%; 4%) (v/v total). The best nutrient of the formulated functional drink is obtained by the composition of 90% snake fruit peel extract, 10% aloe vera, and 4% stevia. The snake fruit peel extract significantly affects the antioxidant activity and total phenol composition, aloe vera extract has an insignificant effect on active compounds, and stevia affects the tannin level of the functional drink.

Vulnerability of subsea permafrost organic matter to degradation after thaw

<p>Subsea permafrost contains a potentially large and vulnerable organic carbon pool that might be or become a source of greenhouse gases to the atmosphere. While organic carbon stocks and vulnerability of terrestrial permafrost are increasingly well constrained, the dynamics of subsea permafrost remain highly uncertain due to limited observational data from these hard-to-access systems. Based on a unique set of drill cores from the near-coastal Laptev Sea, we here assess the vulnerability of subsea permafrost organic matter to degradation after thaw. To that end, we combine biomarker analyses of organic matter above and below the in-situ thaw front with incubation of subsea permafrost material in the laboratory. Biomarker degradation proxies based on the lignin phenol composition of organic matter (acid/aldehyde ratios of syringyl and vanillyl phenols; 3,5-dihydroxybenzoic acid/vanillyl ratio) suggest an overall low degradation state of lignin compared to terrestrial permafrost deposits and marine sediments in the region, and no systematic change across the thaw front. These lignin-based proxies are mostly sensitive to degradation under oxic conditions, i.e. before organic matter burial in subsea permafrost deposits, and less to degradation under anoxic conditions that prevail at the thaw front of subsea permafrost. Lignin phenol proxies will therefore be complemented by other biomarker degradation proxies sensitive to degradation under anoxic conditions, as well as by first data from incubation of subsea permafrost material under cold, anoxic conditions. Together, these data will enhance our understanding of organic matter in subsea permafrost, its vulnerability to degradation after thaw and the potential for greenhouse gas emissions from this system.</p>

Thermal and non-thermal processing of red-fleshed apple: how are (poly)phenol composition and bioavailability affected?

This work fills a gap in the understanding of the effect of processing on the bioavailability of (poly)phenols in fruit products.

Identification of phenolic and alcoholic compounds in wine spirits and their classification by use of multivariate analysis

During the ageing period wine spirits are changing their color, chemical composition and sensory characteristics. These changes should be simply monitored. The aim of this study was to develop partial least squares regression (PLS) models for higher alcohols and phenols in wine spirits as well as to show the feasibility of the NIR spectroscopy combined with chemometric tools to distinguish wine spirits and brandies with different ageing degree. To get the reference values, the usual methods for the analysis of spirits drinks were used. Ethanol, esters, acids, methanol and higher alcohols were studied. Wine spirits and brandies phenol composition was determined by liquid chromatography. Principal component analysis (PCA) was used to classify the wine spirits and brandies according to their phenolic and higher alcohols composition. Moreover, the Partial least squares regression (PLS regression) was used to calibrate and predict expected contents of higher alcohols and phenols in the wine spirits. Success of the classification of samples by ageing based on individual alcohols was 93.8 %, while success of the classification based on individual phenols raised to 100 %. This efficiency of the prediction was evaluated by use of linear discriminator analysis (LDA).

Fabrication of Carbon Paste Electrode Modified with Phenol Imprinted Polyaniline as a Sensor for Phenol Analysis by Potentiometric

A phenol imprinted polymer modified electrode has been prepared by electropolymerization technique in the solution containing aniline as monomer and phenol as a template onto carbon paste electrode surface. A potentiometric method was used to evaluate the performance of the electrodes. Optimization of aniline and phenol composition and a number of polymerization cycles was investigated based on the Nernstian factor. The performance of the electrode sensor is affected by the pH of the analyte solution. Based on the potential response of three different electrodes, it is known that MIP modified electrode has better sensitivity than non-imprinted electrode or bare carbon paste electrode.