Increase In Total Phenolic Content Research Articles

Methyl jasmonate elicitation improves the growth performance and biosynthesis of antioxidant metabolites in Portulaca oleracea through ROS modulation

The application of elicitors is regarded as one of the most efficient strategies for augmenting secondary metabolite contents in medicinal plants. There are numerous reports documenting the impact of methyl jasmonate (meJA) on plant growth and biosynthesis of secondary metabolites. However, the underlying physiological response of the plants towards meJA elicitation is understudied. Thus, the current study focused on evaluating the influence of meJA on growth performance, reactive oxygen species (ROS)/antioxidants crosstalk, and expression of bioactive metabolites in Portulaca oleracea. The seeds of P. oleracea were sown, and the plants were cultivated in pots in nursery settings. P. oleracea plants were sprayed with meJA (ranging from 0.1 to 1.0 mM) on the 35th day after sowing (DAS). The plants were harvested on the 60th DAS. The P. oleracea plants elicited with 1.0 mM meJA exhibited the highest plant height (PH), number of leaves (LN), root length (RL), fresh (FW-P), and dry weights of whole plants (DW-P). The highest increase in total anthocyanin (TAC), total chlorophyll (Total Chl), and total carotenoid (CAR) were observed in plants elicited with 0.4 mM meJA. Meanwhile, the highest increase in total phenolic content (TPC) occurred in plants elicited with 0.6 mM meJA, whereas the highest increase in total flavonoid (TFC) and ascorbic acid content (AsA) was noted in plants elicited with 0.8 mM meJA. The lowest decrease in the stress indicators, malondialdehyde (MDA) and hydrogen peroxide (H2O2) was observed in plants elicited with 0.6 mM meJA. Pearson's analysis and Partial Least Squares Regression (PLSR) were employed in exploring the relationships among all essential parameters. It was found that the antioxidant metabolites and enzymes, particularly the total soluble sugar (TSS), proline, chlorophyll a/chlorophyll b ratio (Chl a/Chl b), and superoxide dismutase (SOD) served as the most essential factors in influencing the growth performance of P. oleracea by modulating the total antioxidant activity (Total AOX) and acting as ROS scavengers. Moreover, meJA elicitation led to the distinct expression of various bioactive compounds, amplifying the medicinal properties of P. oleracea. Overall, this research indicates that meJA enhances growth performance and boosts the production of metabolites possessing medicinal values in P. oleracea.

Effect of processing techniques on functional, antioxidants, and structural properties of finger millet (Eleusine coracana) flour

This study explored the effect of processing methods including milling (control), soaking, parboiling, popping, and germination on functional, antioxidant, structural, and thermal properties of finger millet (Eleusine coracana) flour. These processing techniques increased the water and oil absorption capacity of finger millet flour with an exception for popping method which lacked oil absorption capacity. Additionally, there was also a decrease in bulk density in processed finger millet flour. Antioxidant properties showed a decrease in the anti-nutrient content of millet, and the popping method came out as the best processing method in terms of increase in total phenol content (11.18 mg/g) and antioxidant capacity (40.19%). The tannin's level also declined sharply in all processed millet. The FTIR showed the structural changes by exploiting the changes in bonds and their intensities. Scanning electron microscopy revealed the morphological changes which are attributed to different processing methods. TGA showed that popped finger millet had the highest thermostability. Based on the parameters tested in this research, the popping method came out to show the best results out of all the processing methods in terms of antioxidant and structural properties.

Studies on the Effects of Fermentation on the Phenolic Profile and Biological Activity of Three Cultivars of Kale.

Fermentation is used not only to preserve food but also to enhance its beneficial effects on human health and achieve functional foods. This study aimed to investigate how different treatments (spontaneous fermentation or fermentation with the use of starter culture) affect phenolic content, antioxidant potential, and cholinesterase inhibitory activity in different kale cultivars: 'Halbhoner Grüner Krauser', 'Scarlet', and 'Nero di Toscana'. Chosen samples were further tested for their protective potential against the Caco-2 cell line. HPLC-MS analysis revealed that the fermentation affected the composition of polyphenolic compounds, leading to an increase in the content of rutin, kaempferol, sinapinic, and protocatechuic acids. In general, kale cultivars demonstrated various antioxidant activities, and fermentation led to an increase in total phenolic content and antioxidant activity. Fermentation boosted anti-cholinesterase activity most profoundly in 'Nero di Toscana'. Extracts of spontaneously fermented 'Scarlet' (SS) and 'Nero di Toscana' (NTS) showed cytoprotective properties, as revealed by the malondialdehyde (MDA), lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) assays. Additionally, strong anti-inflammatory activity of NTS was shown by decreased release of cytokines IL-1β and TNF-α. Collectively, the conducted studies suggest fermented kale cultivars as a potential source for functional foods.

The effect of germinated black lentils on cookie quality by applying ultraviolet radiation and ultrasound technology.

Black lentils contain protein, carbohydrates, dietary fiber, minerals, and vitamins, as well as phytochemicals and various bioactive compounds. Ultraviolet (UV) radiation and ultrasound (US) methods are innovative technologies that can be used to increase the efficiency of the germination process in grains and legumes. To improve the nutritional value and bioactive compounds of the cookies, black lentils germinated by applying UV radiation and US technology were used in the cookie formulation. Before the germination process, UV, US, and their combination (UV+US) were applied, and pretreated and unpretreated germinated black lentil flours were used at a level of 20% in the cookie formulation. The results revealed that pretreatment application increased the total phenolic content and antioxidant activity more than the lentil sample germinated without any treatment. In addition, the pretreatments applied further reduced the amount of phytic acid in black lentils and the lowest phytic acid content was obtained with the UV-US combination. Compared to cookies containing unpretreated germinated black lentil flour, higher L* values and lower a* values were obtained in the cookie samples containing pretreated germinated black lentil flour. Cookies containing all pretreated germinated lentils generally exhibited higher Ca and K content. This study demonstrated that UV radiation and US improved the nutritional value and bioactive components of the germinated black lentil flour and the cookies in which it was used, compared to the black lentils germinated without any treatment. PRACTICAL APPLICATION: Pretreatment of black lentils with UV/US application before germination resulted in a greater increase in total phenolic content and antioxidant activity compared to the control sample. The applied pretreatments caused a further decrease in the amount of phytic acid in black lentil samples. Black lentils germinated with the UV+US combination revealed higher Ca, Fe, K, and Mg content compared to the sample germinated without any treatment.

Linking the humification of organic amendments with size aggregate distribution: Insights into molecular composition using FT-ICR-MS

Soil organic matter (SOM) plays a pivotal role in enhancing physical and biological characteristics of soil. Humic substances constitute a substantial proportion of SOM and their increase can improve crop yields and promote agricultural sustainability. While previous research has primarily assessed the influence that humic acids (HAs) derived from natural water have on soil structure, our study focuses on the impact of HAs on soil aggregation under different fertilizer regimes. During the summer cropping season, maize was cultivated under organic and synthetic fertilizer treatments. The organic fertilizer treatment utilized barley (Hordeum vulgare L.) and hairy vetch (Vicia villosa R.) as an organic amendment five days prior to maize planting. The synthetic treatment included a synthetic fertilizer (NPK) applied at South Korea's recommended rates. The organic treatment resulted in significant improvements in the soil aggregates and stability (mean weight diameter, MWD; p < 0.05) compared to the synthetic fertilizer application. These improvements could be primarily attributed to the increased quantity and quality of HAs in the soil derived from the organic amendment. The amount of extracted HAs in the organic treatment was nearly twice that of the synthetic treatment. Additionally, the organic treatment had a 140 % larger MWD and a 40 % increase in total phenolic content compared to the synthetic treatment. The organic treatment also had an increased macronutrient uptake (p < 0.001), an 11 % increase in aboveground maize biomass, and a 21 % increase in grain yield relative to the synthetic treatment. Thus, the enhancement of HA properties through the incorporation of fresh organic manure can both directly and indirectly increase crop productivity.

Valorization of agro-wastes by Bacillus altitudinis XYL17 through simultaneous production of xylanase, xylooligosaccharides, and antioxidant compounds

Bacterial strains were isolated from undisturbed regions of Sikkim Himalaya for the production of highly active xylanase and xylooligosaccharides (XOS). Seven bacterial isolates showed xylanase production while fermenting beechwood xylan (BX) and the agrowastes corncob (CC), rice straw (RS), and sugarcane bagasse (SB). Bacillus altitudinis XYL17, isolated from soil at an elevation of 4083 m, produced the highest amount of xylanase. Maximum xylanase production was observed during BX fermentation after 24 h with the an observed activity of 6576.96 ± 82.75 U/mg. CC was observed to be the best agrowaste substrate for xylanase production with an observed activity of 4150.25 ± 94.64 U/mg. Xylopentaose was the most prominent XOS, with a highest observed content of 11.206 ± 0.331 mg/mL in RS hydrolysate. Significant increase of total phenolic content was observed for hydrolysates of B. altitudinis XYL17 fermented agro-wastes as compared to the control, while there was no significant difference (p < 0.05) in phenolic content between the control and fermented BX. The biotechnological potential of the XOS-rich hydrolysate was demonstrated by the observed radical scavenging, HOCl reducing, and myeloperoxidase (MPO) inhibitory activity. MPO inhibitory IC50 of 6.88 mg/mL and 9.4 mg/mL was observed for hydrolysates of SB and CC, respectively. We conclude that B. altitudinis XYL17 can be used for the valorization of agricultural wastes for the simultaneous production of highly efficient xylanase along with XOS and other antioxidant compounds.

Evaluation of modified atmosphere packaging system developed through breathable technology to extend postharvest life of fresh muscadine berries.

Muscadine grapes (Vitis rotundifolia Michx.) are delicate in nature with short shelf life. Postharvest technologies like modified atmosphere packaging (MAP) with reduced oxygen (O2) and elevated carbon dioxide (CO2) could increase the postharvest storage life with better quality. In the current experiment, physical and biochemical quality attributes of black and bronze cultivars of muscadine grapes ('Supreme' and 'Granny Val', respectively) were evaluated in active MAP. Fruit were packed in plastic trays, sealed with impermeable film, and CO2 was introduced into the package. The MAP was created by a rigid microperforated plastic patch coated with a proprietary semipermeable resin, which was applied over a hole in the tray; packages with the same size hole without a patch were the control. Fruit were stored at 4°C for 42 days (6 weeks). MAP resulted in significantly lower decay incidence and better retention of fruit firmness for up to 28 days of storage in both cultivars as well as reducing color changes in 'Supreme' fruit. Although MAP did not affect the biochemical quality of muscadine grapes, total antioxidants increased initially and then decreased during storage, irrespective of packaging treatments. A significant linear increase in total phenolic content was also found during storage, regardless of treatments applied. Overall, the results of the current study demonstrate that MAP can be an affective technology to increase storage duration of muscadines with better retention of physical quality, without affecting the biochemical attributes.

Effects of steam explosion on raspberry leaf structure and the release of water-soluble nutrients and phenolics

Raspberry leaves were subjected to steam explosion at 0.5 and 1.0 MPa for 60–120 s, aiming to disrupt their physical and chemical structure and, consequently, promote the release of phenolic compounds into the leaf aqueous infusion. Under optimal condition of 1.0 MPa for 60 s, steam explosion led to a notable 23 % increase in total phenolic content, a 29 % elevation in ABTS radical scavenging capacity, and a 13 % rise in DPPH radical scavenging capacity of the aqueous infusion. Utilizing UHPLC-Q-TOF-MS/MS and UHPLC-QE-MS/MS techniques, respectively, a total of 39 phenolic compounds were identified from raspberry leaves, and the changes in the contents of the most important 11 species were analyzed following steam explosion. Through correlation analysis and considering the content of each phenolic compound, it was inferred that the heightened antioxidant capacity of the aqueous infusion primarily stemmed from a substantial increase in the release of ellagic acid after steam explosion.

Effect of low intensity direct-current electric field on anti-browning of apple juice: Enzyme inactivation kinetics and juice properties

For the first time, the efficacy of low intensity (1–7 V/cm) direct-current (DC) electric field in preventing browning in apple juice is examined. The results show that applying a 5 V/cm electric field can inactivate 89.24% of polyphenol oxidase (PPO) within 90 min and achieve complete inactivation of peroxidase (POD) within 70 min, maintaining the juice temperature below 30 °C throughout the process. The Weibull model fits the PPO and POD inactivation effectively, suggesting varied responses among isoenzymes. Under the optimal conditions (5 V/cm for 90 min), a 15.89% increase in total phenolic content (TPC) was observed alongside significant improvements in antioxidant activity. Furthermore, this method preserved the natural flavor and lightened the color of the apple juice, enhancing its sensory appeal. These findings indicate that low intensity DC electric field is an innovative and effective choice for preventing juice browning, offering significant potential for application in the food industry.

Energy analysis and quality characteristics of flaxseed oil by using an infrared rotary dryer

An infrared (IR) rotary dryer was designed and fabricated to sterilize flaxseeds under different experimental treatments. The investigations were conducted under varying IR intensities (882, 964, 1050, and 1140 W/m2) and exposure times (6, 9, 12, and 15 min). Data analysis showed the minimum amount of specific energy consumed at 882 W/m2 and 6 min for the studied varieties Sakha 3 and Sakha 6. The highest thermal efficiency belonged to the highest radiation intensity and the lowest exposure time, with values of 77.26 % and 86.17 % for Sakha 3 and Sakha 6, respectively. Different IR intensities caused an increase in oil yield (OY), acid value (AV), and peroxide value (PV). For example, 1050 W/m2 for 15 min showed the highest OY for Sakha 3 (37.37 %), whereas 964 and 1050 W/m2 for 12 min reported the highest activity for Sakha 6 (43.20 and 43.43 %, respectively); 1140 W/m2 was the intensity that recorded the highest content of AV (range of 2.67–3.93 mg KOH/g for Sakha 3 and 3.19–4.22 mg KOH/g for Sakha 6) and PV (range of 4.05–6.91 meq. O2/kg for Sakha 3 and 5.21–5.92 meq. O2/kg for Sakha 6). Moreover, increasing IR intensity caused an increase in total phenolic content. The maximum amount was obtained at 1140 W/m2 for 12 min (153.27 and 154.59 mg GAE/100 g sample for Sakha 3 and 6, respectively) without significant changes at 1050 W/m2 and 12 min. For radical scavenging activity, 1050 W/m2 at 9, 12, and 15 min represented the highest activity for Sakha 3 (range of 30.27%–32.64 %) and Sakha 6 (range of 36.58%–37.37 %). Thus, IR pretreatment at 1050 W/m2 and duration between 12 and 15 min is recommended for Sakha 3 and 6. After the oil extraction and storage period (4 weeks), PV increased in all the investigated oil samples. In general, the heat-treated seeds’ oil will stay stable and maintain quality as long as the seeds are stored before the oil is extracted.

Elicitation as a Process of Enhancing Bioactive Compounds Concentration in Sprouts

During growth, plants produce bioactive compounds—secondary metabolites. Their concentration can be stimulated by the presence of a stressful factor—an elicitor. Since chlorine dioxide is commonly used in water plants to disinfect drinking water, its application as a plant elicitor seems to be very attractive. The aim of this work was to investigate the influence of a new elicitor, ClO2, on the quality of seeds and bioactive compounds of sprouts. Elicitation of radish and broccoli seeds using ClO2 solutions did not significantly reduce their germination percentage (GP remained over 90%). Radish sprouts sprouted from seeds elicited in chlorine dioxide solutions with concentrations up to 800 ppm did not differ statistically significantly in terms of polyphenol content. Sprouts which were grown in the presence of ClO2 contained significantly fewer polyphenolic compounds. Elicitation of broccoli seeds in 800–1000 ppm ClO2 solutions causes an increase in total phenolic content and concentration of ascorbic acid in sprouts. Elicitation in chlorine dioxide solutions not only increased concentrations of selected bioactive compounds but also improved the microbiological quality of sprouts.

Effect of Copper Sulfate Induction on Phyllanthus tenellus Roxb. Total Phenolic and Flavonoid Content

Aims: Plants need an appropriate amount of nutrients such as copper for growth and development. However, excess of copper may interrupt plant development and cause stress that led to biochemical compounds being synthesized. The influence of a high copper sulfate concentration on phenolic and flavonoid content in Phyllanthus tenellus plants was investigated.&#x0D; Place and Duration of Study: The experiment was conducted in a government compound at MARDI Serdang, Selangor, Malaysia (2° 59' 31.7292'' N 101° 41' 56.706'' E), from April 2021 to Jun 2021.&#x0D; Methodology: The experiment was conducted using a vertical column planting system under a side-netted rain shelter. The plants were subjected to 0.5 M copper sulfate sprayed after 60 days of planting and harvested 0.5, 1.5, 3, 6, 12 and 24 h after sprayed for further analysis. Total phenolic content was calculated as mg gallic acid equivalent and total flavonoid content was measured as quercetin equivalent.&#x0D; Results: Highest total phenolic and flavonoid content was detected after 0.5 hours of copper sulfate application and started to decrease towards 24 hours after sprayed. Treated samples showed a 1.18-fold increase in total phenolic content and 1.4-fold increase in total flavonoid content compared to control untreated samples after 0.5 hours of sprayed. Control samples showed stability in both total phenolic and flavonoid content throughout the harvesting periods. Phenolic is the major secondary metabolites in Phyllanthus tenellus plants.&#x0D; Conclusion: Data revealed that the application of 0.5 M copper sulfate is able to enhance total phenolic and flavonoid content in Phyllanthus tenellus plants. The study suggested that the optimum harvesting time is 0.5 hours after copper sulfate application.

Powder shampoo formulation with antioxidant activity: in vitro perspectives

PurposeThe purpose of the study was to develop a powder shampoo with antioxidant attributes.Design/methodology/approachDry shampoo compositions were formulated containing alpha olefin sulfonate (AOS), sodium cocoyl isethionate (SCI), microcrystalline cellulose, mannitol, carboxymethyl cellulose, maltodextrin and sodium benzoate with or without extract of Cinnamomum zeylanicum bark. Cinnamon extract was chosen for this study owing to its ubiquitously known antioxidant attributes. The formulations were tested for detergency action and antioxidant potential in vitro.FindingsCinnamomum zeylanicum extract exhibited noticeable antioxidant activity in vitro. The authors observed that addition of the bark extract to the shampoo formulation was associated with remarkable increase in total phenolic content, total antioxidant activity and radical scavenging activity without any effect on detergency action.Research limitations/implicationsThis preliminary study provides a powder shampoo formulation which exhibits antioxidant attributes as a result of incorporation of cinnamon bark extract. Clinical efficacy of the formulation remains to be tested.Practical implicationsOwing to the powder format of the shampoo, the formulation can be manufactured with ease and economically. Functionalizing the formulation with enhancement of antioxidant activity by incorporation of cinnamon bark extract may be associated with beneficial clinical outcomes, which remains to be tested.Social implicationsThe proposed formulation may be stored and sold in eco-friendly packing material, thus could pave the way for reducing the burden of plastic consumption by the shampoo industry.Originality/valueThe present work demonstrates that incorporation of cinnamon bark extract to a powder shampoo formulation, containing AOS and SCI as principle surfactants, significantly enhances its antioxidant attributes.

Thermal Stability and Antioxidant Activity of Bioactive Compounds in Bread Enriched with Bee Pollen and Bee Bread.

Bee pollen (BP) and bee bread (BB) are natural food sources containing a wide variety of bioactive compounds, complementing their rich nutritional composition. These bee products are being explored to empower functional foods, with the term functionality being dependent on the bioactive compounds added to the food matrix. However, there is not enough evidence of the effect of heat on these compounds during food processing and production and how it impacts their biological activity. Here, we enriched traditional bread by adding BP and BB at different proportions of 1 to 5% and tested the thermal stability of their bioactive compounds through several spectroscopic and chromatographic analyses. Adding bee pollen and bee bread to bread resulted in a 4 and 5-fold increase in total phenolic content, respectively. While not all the 38 phenolic and phenolamide compounds identified in the raw BP and BB were detected in the processed bread, phenolamides were found to be more resilient to baking and heat treatment than flavonoids. Still, the enriched bread's antioxidant activity improved with the addition of BP and BB. Therefore, incorporating bee products into heat-treated products could enhance the functionality of staple foods and increase the accessibility to these natural products.

Incorporation of jaggery in beetroot jam enhances its antioxidant properties with acceptable sensory and physicochemical profile

With the growing consumer interest in incorporating healthier foods in diet, the market for functional foods is increasing. The present study focused on developing beetroot jam (BJ) using jaggery (non-centrifugal sugar) as a sweetener. Formulation of BJ was carried out by partial replacement of sugar with jaggery and evaluated for sensory attributes (odor, color, spreadability, taste, acid attribute and overall acceptance) using compromised acceptance threshold (CAT) and the hedonic rejection threshold (HRT). The incorporation of jaggery in BJ shifted the acceptances of tatse (CATt = 82.56%), color (CATc = 78.82%), odor (CATo = 73.16%), acid attribute (CATac = 65.01%), overall acceptance (CAToc = 65.61%), and spreadabality (CATs=50.94%). This depreciation, however, did not result in sensory rejection of the jam odor, color, and taste. On the other hand, a sensory rejection started to occur for spreadability, acid attribute, and overall acceptance at jaggery concentrations of 66.92%, 88.1%, and 77.49%, respectively. Physicochemical characterization of BJ for parameters such as color, texture, and rheological properties was carried out. Thermal behaviour of BJ was studied using differential scanning calorimetry (DSC), whereas chemical characterization was performed using Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Assessment of nutraceutical and nutritional properties of BJ revealed that an increase in jaggery proportion resulted in an increase in total phenolic content (TPC) and total flavonoid content (TFC), where BJ100 showed the highest TPC and TFC of 2.58 mg GAE/g and 1.08 mg QE/g, respectively. The increase in the polyphenols in BJ correlated positively with the antioxidant activities evaluated through DPPH, FRAP, and ABTS assays. Lastly, the proximate analysis of BJ was carried out for protein, fat, carbohydrates, sugar, and fibre content.

Postharvest quality evaluation on the hot water-dipped Zingiber officinale rhizomes stored at low-temperature storage

Storing ginger at chilling temperature will reduce its postharvest quality as they are prone to chilling injury (CI). Therefore, a study on hot-water dip treatment in alleviating CI in 'Bentong' ginger rhizome on physical and chemical properties was conducted. Fresh ginger rhizomes were harvested in the 9th month after planting. The fresh and cleaned rhizomes were hot-water treated at 45°C for 0, 5, 10 and 15 mins before being packed in a box and stored at 5°C for 0, 8 and 16 days. There was a significant interaction effect between dipping and storage durations on the physical and chemical properties of the rhizome. Exposed rhizome for 5, 10 and 15 mins was observed to maintain the ho and L* of the rhizome after storage at 5°C. The decreases in h° from yellow to slightly brown also indicated rhizome browning. Rhizome held at 45°C for 5 mins managed to reduce browning as compared to other durations. In addition, dipping for 15 mins resulted in a significant increase in total phenolic content, total flavonoid content and 6-gingerols. While 6-shogaols was maintained at 45°C for 5 mins. Preconditioning by the hot-water treatment could induce chilling tolerance upon storage at chilling temperature.

Inactivation of Alicyclobacillus acidoterrestris vegetative cells and spores induced by atmospheric cold plasma

This study aimed to inactivate Alicyclobacillus acidoterrestris vegetative cells and spores (107–108 CFU/mL) using atmospheric cold plasma (ACP). Alicyclobacillus acidoterrestris vegetative cells decreased by 6.63 and 6.47 log under only ACP treatment of 30 kV for 6 min in saline solution and apple juice, respectively. ACP was less effective against spores, resulting in 2.64 and 2.43 log reductions at the same treatment parameter. However, better inactivation (4.03 log and 3.95 log) was achieved in apple juice and saline solution using ACP at 30 kV combined with mild heat (85 °C) for 6 min. Morphological observation and intracellular substance release revealed severe structural damage to spores induced by ACP. The application of ACP resulted in improved color, reduced pH, and increased levels of total phenolic content and total soluble solids in apple juice. This study offers an effective method for inactivating Alicyclobacillus acidoterrestris in apple juice. Industrial relevanceThe application of atmospheric cold plasma in combination with mild heat to effectively inactivate Alicyclobacillus acidoterrestris in apple juice offers a promising method for ensuring juice product quality. The enhancement of color, reduction in pH, and increase in total phenolic content and total soluble solids further underscore the potential benefits of this technique for enhancing the sensory attributes of apple juice. This study offers a potential approach that may directly contribute to enhancing production practices and product value.

Increase in Total Phenolic Content and Antioxidant Capacity in Wines with Pre- and Post-Fermentation Addition of Melissa officinalis, Salvia officinalis and Cannabis sativa

Herbs are considered substantial sources of antioxidant compounds, playing an important role in medicines, cosmetics, and distillates. Although they have been used in wine since ancient times, especially in Mediterranean regions, there is limited scientific evidence on how the addition of herbs into wine affects its properties. The aim of the present study was to determine the effects of three herbs, Salvia officinalis, Melissa officinalis and Cannabis sativa, with direct extraction in two different conditions: in must (pre-fermentation addition) and in wine (post-fermentation addition) and investigate potential differences between them. Three Greek indigenous grape varieties of Vitis vinifera L. were evaluated (Roditis, Muscat, Fokiano). The extractability of phenolic compounds and the antioxidant capacity of the produced wines were determined by the Folin–Ciocalteu and DPPH methods, respectively. Moreover, HPLC analysis was conducted to identify and quantify rosmarinic acid and caffeic acid, two main components of many Lamiaceae plants. The results indicate that the post-fermentation addition of herbs leads to a significant increase in antioxidant activity and phenolic compounds compared to blank wine. In most cases, the increase is significantly higher in comparison with pre-fermentation addition. Wine, upon the addition of Melissa officinalis, was found to extract the highest amount of total phenols compared to the other two herbs.

Biocontrol of chocolate spot disease of broad bean (Vicia faba L.) caused by Botrytis fabae using biosynthesized reduced graphene oxide/silver nanocomposite

This study was demonstrated to investigate the effects of reduced graphene oxide/silver nanocomposite (rGO/AgNC) on controlling the chocolate spot disease of broad bean (Vicia faba L.) caused by Botrytis fabae. rGO/AgNC was green synthesized using the cell-free supernatant of Escherichia coli D8 in the presence of sunlight and room temperature. rGO/AgNC revealed a broad UV–vis absorption peak at 433 nm. Transmission electron microscopy (TEM) images of rGO/AgNC confirmed the presence of spherical-shaped silver nanoparticles (AgNPs) with an average size of 7–26 nm. Zeta analysis of rGO/AgNC displayed their positive charge (+18.9 mV) and the good dispersion of AgNPs on the surface of rGO. rGO/AgNC had good antifungal activity against B. fabae in a dose-dependent pattern. In vivo, rGO/AgNC-treatment study on faba bean plants showed the biocidal action of rGO/AgNC (150 μg/ml) against B. fabae and completely prevented the pathogen infection. In addition, there was an increase in total phenolic content, peroxidase, and polyphenol oxidase activity, and protein content of rGO/AgNC-treated plants. Plants treated with rGO/AgNC displayed a typical cell morphology in their ultrastructure, including cell membranes and chloroplasts with ellipsoidal shapes and large starch grains. These are all encouraging findings for the use of the biosynthesized rGO/AgNC as a safe and efficient antifungal agent against B. fabae.

The Influence of Bee Bread on Antioxidant Properties, Sensory and Quality Characteristics of Multifloral Honey

The aim of this study was to investigate the influence of bee bread addition on the phenolic content, antioxidant properties, sensory and quality characteristics of the multifloral honey. On the base of results obtained, it was stated that an enrichment of honey with bee bread led to an significant increase in total phenolic content (from 30.75 to 158.96 mg GAE/100 g), total flavonoids content (from 2.77 to 21.15 mg QE/100 g), and phenolic acids content (from 11.02 to 35.47 mg CAE/100 g). Gallic acid was the predominating phenolic acid, while quercetin was the main determined flavonoid. A significant elevation of the phenolic content resulted in an increase in antioxidant capacity of the honey. However, an addition of bee bread to the honey led to the unfavorable changes of its sensory characteristics. The decrease in clarity, and uniformity of color and brightness was detected. In the case of consistency, the decrease in smoothness and meltability was found along with an increase in the feeling of sandiness. The assessment of taste showed a significant increase in acid taste, sharpness, bitterness and durability of the aftertaste, with a decrease in sweetness. The addition of bee bread to the honey caused a significant increase in water-insoluble substances content, free acidity, specific conductivity and proline level. At the same time, a decrease in the content of glucose and fructose was observed.