scholarly journals Morphology, physicochemical properties and antioxidant capacity of bee pollens

2019 ◽  
Vol 37 (No. 1) ◽  
pp. 1-8 ◽  
Author(s):  
Roman Bleha ◽  
Tatiana Shevtsova ◽  
Andrej Sinica ◽  
Vojtech Kruzik ◽  
Jan Brindza
Keyword(s):  
Physicochemical Properties ◽  
Antioxidant Capacity ◽  
Ftir Spectroscopy ◽  
Water Activity ◽  
Antioxidant Properties ◽  
Pollen Grains ◽  
Botanical Origin ◽  
Colour Parameters

Six supposedly unifloral bee pollens of various botanical origins were characterised by morphometry, SEM, CIE L*a*b* colour parameters and FTIR spectroscopy. Botanical origin and homogeneity of bee pollens were verified by colour and morphology of pollen grains. Water activity, moisture and antioxidant capacity of bee pollens were also evaluated. The results were discussed in terms of connection between botanical origin, composition and antioxidant properties of pollen materials.

scholarly journals Relationships Linking the Colour and Elemental Concentrations of Blossom Honeys with Their Antioxidant Activity: A Chemometric Approach

Agriculture ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 702
Author(s):  
Monika Kędzierska-Matysek ◽  
Anna Teter ◽  
Małgorzata Stryjecka ◽  
Piotr Skałecki ◽  
Piotr Domaradzki ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Physicochemical Properties ◽  
Black Locust ◽  
Antioxidant Properties ◽  
Principal Component ◽  
Botanical Origin ◽  
Antioxidant Parameters ◽  
Colour Parameters ◽  
Hue Angle ◽  
Chemometric Approach

The antioxidant activity of honey depends on the botanical origin, which also determines their physicochemical properties. In this study, a multivariate analysis was used to confirm potential relationships between the antioxidant properties and colour parameters, as well as the content of seven elements in five types of artisanal honey (rapeseed, buckwheat, linden, black locust, and multifloral). The type of honey was found to significantly influence most of its physicochemical properties, colour parameters, and the content of potassium, manganese and copper. Antioxidant parameters were shown to be significantly positively correlated with redness and concentrations of copper and manganese, but negatively correlated with the hue angle and lightness. The principal component analysis confirmed that the darkest buckwheat honey had the highest antioxidant activity in combination with its specific colour parameters and content of antioxidant minerals (manganese, copper and zinc). The level of these parameters can be potentially used for the identification of buckwheat honey.

scholarly journals Hybrid Drying of Murraya koenigii Leaves: Energy Consumption, Antioxidant Capacity, Profiling of Volatile Compounds and Quality Studies

Processes ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 240 ◽  
Author(s):  
Choong Oon Choo ◽  
Bee Lin Chua ◽  
Adam Figiel ◽  
Klaudiusz Jałoszyński ◽  
Aneta Wojdyło ◽  
...  
Keyword(s):  
Energy Consumption ◽  
Antioxidant Capacity ◽  
Volatile Compounds ◽  
Water Activity ◽  
Specific Energy ◽  
Activity Analysis ◽  
Drying Methods ◽  
Murraya Koenigii ◽  
Hot Air ◽  
Colour Parameters

This study aims to reduce the amount of specific energy consumed during the drying of fresh Murraya koenigii leaves by comparing four drying methods: (1) convective hot-air drying (CD; 40, 50 and 60 °C); (2) single-stage microwave-vacuum drying (MVD; 6, 9 and 12 W/g); (3) two-stage convective hot-air pre-drying followed by microwave-vacuum finishing–drying (CPD-MVFD; 50 °C, 9 W/g); and (4) freeze-drying as a control in the analysis sections. The drying kinetics were also modelled using thin-layer models. The quality parameters of dried M. koenigii leaves were measured including total polyphenolic content (TPC), antioxidant capacity (ABTS and FRAP), profiling of volatile compounds, colour analysis and water activity analysis. Results showed that CPD-MVFD effectively reduced the specific energy consumption of CD at 50 °C by 67.3% in terms of kilojoules per gram of fresh weight and 48.9% in terms of kilojoules per gram of water. The modified Page model demonstrated excellent fitting to the empirical data obtained. FD showed promising antioxidant activity. The major contributor of antioxidant capacity was TPC. The volatile compounds profiled by gas chromatography-mass spectrometry, namely, β-phellandrene (31%), α-pinene (19.9%), and sabinene (16%) were identified as the major compounds of dried M. koenigii leaves. Colour analysis showed MVD’s high performance in preserving the colour parameters of M. koenigii leaves under all conditions. The colour parameters were correlated to the antioxidant capacity and TPC. Water activity analysis showed that the water activity of M. koenigii leaves for all drying methods indicating that the conditions were microbiologically and shelf-stable. Pearson correlation showed the colour parameters of the leaves had a strong correlation to TPC. Overall, MVD showed promising energy consumption reduction and recovery in TPC and volatile compounds.

scholarly journals Evaluation of Nanostructured Lipid Carriers Produced with Interesterified Buriti Oil

2020 ◽  
Vol 58 (3) ◽  
pp. 284-294
Author(s):  
Lívia Viana de Castro Reis ◽  
Karina Magna Leão ◽  
Paula Speranza ◽  
Ana Paula Badan Ribeiro ◽  
Gabriela Alves Macedo ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Physicochemical Properties ◽  
Antioxidant Capacity ◽  
High Stability ◽  
Antioxidant Properties ◽  
Structured Lipids ◽  
Nanostructured Lipid Carriers ◽  
Commercial Application ◽  
Wide Range ◽  
Buriti Oil

Research background. Extracted from the pulp of an Amazonian fruit, buriti oil is rich in micronutrients with antioxidant properties and has high biological value. The few studies available indicate that this oil could be used in a wide range of applications; however, there are no studies that work on the improvement in the characteristics of this oilfor commercial application. The enzymatic interesterification is one of the tools available to improve the properties of oils and fats and our recent studies demonstrated that the lipase could specifically act on buriti oil to produce structured lipids rich in oleic acid, while preserving most of minority compounds present in this oil. Still looking for ways to expand applicability of this raw oil, in this recent work, we are interested in studying how is the behavior of this structured oil in nanostructured lipid carriers (NLCs). Experimental approach. Samples were stored at 4 and 25 °C for 30 days and their physicochemical properties were evaluated. Results and conclusions. The results showed that the interesterification formed more unsaturated triacylglycerols (TAGs) and NLCs prepared with interesterified buriti oil presented small droplets than NLCs with original buriti oil. Particles remained stable throughout the storage period and NLCs exhibited complex polymorphism with the presence of three crystalline forms. The ORAC value was approximately 23 % higher in nanolipid carries with structured lipids in comparison with the nano lipid carriers with original buriti oil, and the FRAP value, 16 % higher, demonstrating the influence of interesterification on the antioxidant activity of nanocarriers. Thus, NLCs prepared with interesterified buriti oil exhibit smaller droplets, high stability and antioxidant capacity and have potential for nutritional and biological applications. Novelty and scientific contribution. This research showed that interesterification positively influenced the physicochemical properties of NLCs, producing oils rich in oleic acid, high stability and antioxidant capacity. Therefore, it may be interesting to use these nanocarriers to obtain efficient carrier systems for future applications.

scholarly journals In-Vitro Antioxidant Capacity and Bioactive Compounds Preservation Post-Drying on Berrycacti (Myrtillocactus geometrizans)

2017 ◽  
Vol 6 (4) ◽  
pp. 121 ◽  
Author(s):  
Priscila Desiree Santiago-Mora ◽  
Anaberta Cardador-Martinez ◽  
Carmen Tellez-Perez ◽  
Jose Gerardo Montejano-Gaitan ◽  
Sandra T. Martin del Campo
Keyword(s):  
Antioxidant Capacity ◽  
Shelf Life ◽  
Bioactive Compounds ◽  
Antioxidant Properties ◽  
Added Value ◽  
Drying Methods ◽  
Colour Parameters ◽  
Soluble Phenols ◽  
Instant Controlled Pressure Drop

Berrycactus is a cactus which does not require special agronomic attention, the berries are consumed locally and its commercialization is rather scarce because of the extremely short shelf-life. The significance of the application of any drying methods used to extend the shelf-life on the berrycacti is currently unknown. The aim of this work was to preserve berrycacti (Myrtillocactus geometrizans) and test the bioactive compounds and antioxidant capacity using two distinctive drying methods, freeze-drying (FD) and Instant Controlled Pressure Drop (DIC). Ripe berrycacti was chosen for the drying procedures because the antioxidant capacity and levels of soluble phenols and betalains were at their peak. Colour, phenols, non-extractable polyphenols, tannins, betalains, and antioxidant capacity were considered as factors to determine drying efficacy. Only colour parameters could discriminate between FD and DIC, concluding that both methods are suitable and efficient for preservation of antioxidant properties and retention of bioactive compounds. Both drying methods demonstrated higher in-vitro antioxidant capacity compared to the fresh fruit; highlighting the increase of non-extractable polyphenols and condensed tannins, and good retention of betalains and ascorbic acid after the drying treatments. This research points to use this sustainable crop to provide added value to berrycacti while considering this fruit as functional food due to the antioxidant capacity present even after being processed.

HPLC Screening of Bioactives Compounds and Antioxidant Capacity of Different Hypericum Species

2018 ◽  
Vol 69 (2) ◽  
pp. 305-309 ◽  
Author(s):  
Daniela Gitea ◽  
Simona Vicas ◽  
Manuel Alexandru Gitea ◽  
Sebastian Nemeth ◽  
Delia Mirela Tit ◽  
...  
Keyword(s):  
Antioxidant Capacity ◽  
Methanol Extract ◽  
Antioxidant Properties ◽  
Polyphenolic Compounds ◽  
The Other ◽  
The North ◽  
Western Area ◽  
North Western ◽  
Hypericum Species ◽  
Biological Actions

Our study compares the content in polyphenolic compounds and hypericin, in four species of Hypericum - H. perforatum L., H. maculatum Cr., H. hirsutum L., H. tetrapterum Fr. (syn. Hypericumacutum Mnch.) harvested from spontaneous flora in the north-western area of Transylvania, Romania. These species represent an important source of such compounds with different biological actions. After making the extracts, they were subjected to HPLC-SM analysis. The presence of rutoside in the largest amount (462.82 mg %) in the H. perforatum extract was observed, this containing most of the flavonoid heterosides. For the species H. maculatum, the presence in a much higher amount of the hyperoside (976.36 mg %) is characteristic compared to the other species. Quercetol is the best represented of the flavonoid aglycons, its concentration being the highest in H. hirsutum (659.66 mg %). The hypericin content ranges from 0.2171 g % in the H. tetrapterum extract, to 0.0314 g % in the methanol extract of H. maculatum.The highest antioxidant properties measured by FRAP method were recorded in the case of H. perforatum and H. maculatum.

scholarly journals Variation of the Polyphenolic Composition and Antioxidant Capacity of Freshly Prepared Pomegranate Leaf Infusions over One-Day Storage

Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1187
Author(s):  
Manyou Yu ◽  
Irene Gouvinhas ◽  
Ana Barros
Keyword(s):  
Antioxidant Capacity ◽  
Gallic Acid ◽  
Antioxidant Properties ◽  
Punica Granatum ◽  
Added Value ◽  
Plant Materials ◽  
Polyphenolic Composition ◽  
Punica Granatum L ◽  
Intensive Search ◽  
By Products

In recent decades, an intensive search for natural and novel types of antioxidant polyphenolics has been carried out on numerous plant materials. However, the current literature has very little information on their storage stability in the form of freshly prepared infusions. This study aims to characterize the polyphenolic composition and the antioxidant capacity of pomegranate (Punica granatum L.) leaf infusions over one-day storage (analyzed at 0, 2, 4, 6, 8, and 24 h). Spectrophotometric evaluation demonstrated that the infusion presented no significant changes in the content of total phenols (131.40–133.47 mg gallic acid g−1) and ortho-diphenols (239.91–244.25 mg gallic acid g−1). The infusion also maintained high stability (over 98% and 82%, respectively) for flavonoids (53.30–55.84 mg rutin g−1) and condensed tannins (102.15–124.20 mg epicatechin g−1), with stable (>90%) potent antioxidant capacity (1.5–2.2 mmol Trolox g−1) throughout 0–24 h storage. The main decrease was observed during 0–2 h storage of flavonoids, 8–24 h storage of tannins, and 0–4 h storage of antioxidant capacity. Chromatographic analysis further revealed that 7 decreased and 11 increased compounds were found within 0–24 h storage. The good stability of the total polyphenolics and antioxidant properties might be related to the complex conversion and activity compensation among these compounds. The findings suggest that pomegranate leaf infusion could be of great interest in the valorization of high added-value by-products and in the application of green and functional alternatives in the food-pharma and nutraceutical industries.

scholarly journals Isolation and structural elucidation of dimeric epigallocatechin-3-gallate autoxidation products and their antioxidant capacity

2021 ◽  
Author(s):  
Julian Alfke ◽  
Uta Kampermann ◽  
Svetlana Kalinina ◽  
Melanie Esselen
Keyword(s):  
Antioxidant Capacity ◽  
Antioxidant Properties ◽  
Cd Spectroscopy ◽  
Trolox Equivalent Antioxidant Capacity ◽  
Published Data ◽  
Dietary Polyphenols ◽  
Cellular Effects ◽  
The Impact

AbstractDietary polyphenols like epigallocatechin-3-gallate (EGCG)—which represents the most abundant flavan-3-ol in green tea—are subject of several studies regarding their bioactivity and health-related properties. On many occasions, cell culture or in vitro experiments form the basis of published data. Although the stability of these compounds is observed to be low, many reported effects are directly related to the parent compounds whereas the impact of EGCG degradation and autoxidation products is not yet understood and merely studied. EGCG autoxidation products like its dimers theasinensin A and D, “P2” and oolongtheanin are yet to be characterized in the same extent as their parental polyphenol. However, to investigate the bioactivity of autoxidation products—which would minimize the discrepancy between in vitro and in vivo data—isolation and structure elucidation techniques are urgently needed. In this study, a new protocol to acquire the dimers theasinensin A and D as well as oolongtheanin is depicted, including a variety of spectroscopic and quadrupole time-of-flight high-resolution mass spectrometric (qTOF-HRMS) data to characterize and assign these isolates. Through nuclear magnetic resonance (NMR) spectroscopy, polarimetry, and especially circular dichroism (CD) spectroscopy after enzymatic hydrolysis the complementary atropisomeric stereochemistry of the isolated theasinensins is illuminated and elucidated. Lastly, a direct comparison between the isolated EGCG autoxidation products and the monomer itself is carried out regarding their antioxidant properties featuring Trolox equivalent antioxidant capacity (TEAC) values. These findings help to characterize these products regarding their cellular effects and—which is of special interest in the flavonoid group—their redox properties.

Evaluation of solid state of rice flours produced by different milling processes using ATR-FTIR spectroscopy

2021 ◽  
Author(s):  
Daitaro Ishikawa ◽  
Jiamin Yang ◽  
Chiaki Ichikawa ◽  
Tomoyuki Fujii
Keyword(s):  
Solid State ◽  
Ir Spectra ◽  
Ftir Spectroscopy ◽  
Water Activity ◽  
Rice Flour ◽  
Milling Process ◽  
Adsorption Properties ◽  
Water Molecules ◽  
Rice Flours ◽  
Changes Of State

ABSTRACT This study evaluated the influence of the milling process on solid state of rice flours according to water activity using ATR-FTIR. A band at 1740 cm−1 attributed to the C=O stretching of lipids was detected for crystalline samples, and it disappeared at a high aw range. The CH band at 2930 cm−1 of crystalline samples gradually shifted to a higher wavenumber with aw. This band of the α-formed and wet-milled samples shifted to higher wavenumbers above 0.8aw. A band due to OH stretching mode in the 3500-3000 cm−1 region did not shift with aw. The result obtained from IR spectra suggests that the parameter K calculated by Guggenheim–Anderson–de Boar model reflected not only the interaction between water molecules but also the changes of state in solids. Consequently, the results from this study provide insights about the adsorption properties of nonideal solids such as rice flour.

Antioxidant Properties and Polyphenol Screening of the Leaves of Native Hungarian Oak (Quercus) Species

2021 ◽  
Vol 17 ◽  
Author(s):  
Tamás Hofmann ◽  
Eszter Visi-Rajczi ◽  
Levente Albert
Keyword(s):  
Antioxidant Capacity ◽  
State Of The Art ◽  
Antioxidant Properties ◽  
Antibacterial Properties ◽  
Flavonoid Glycosides ◽  
Waste Biomass ◽  
Quercus Species ◽  
Tandem Mass Spectrometric ◽  
Liquid Chromatographic ◽  
Phenolic Acid Derivatives

Background: Due to their ecological significance and timber value, Quercus species are especially important in Hungary. Nevertheless, the leaves of these species lack a dedicated utilization field and are considered a waste biomass. Materials and Methods: The present study comprehensively analyses three selected oak species (Q. petraea, Q. pubescens, Q. cerris) native to Hungary to assess their antioxidant capacity (FRAP, ABTS, DPPH) and provide information on their polyphenol pool using state-of-the-art liquid chromatographic/tandem mass spectrometric technique. To the best of our knowledge, no such investigation has yet been conducted for the assigned species. Results: According to the results, the antioxidant capacity of the three species’ leaves are roughly equal. Altogether, 109 compounds have been tentatively identified and described, including phenolic acid derivatives, tannins, flavonoid glycosides, and catechins. Compared to other oak leaf samples and other types of plant tissues, the investigated samples contained a large number (24) of acylated polyphenols. Conclusion: The recent findings on the excellent antioxidant and antibacterial properties of acylated polyphenols suggest that the investigated samples could also be beneficial to human health, requiring further analysis.

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