Gallic Acid Content Research Articles

Evaluation of gallic acid on membrane damage of Yersinia enterocolitica and its application as a food preservative in pork

This study was aimed to examine the membrane damage mechanism of gallic acid (GA) on Yersinia enterocolitica BNCC 108930, and to explore whether GA can prolong the shelf life of pork. The minimal inhibitory concentration (MIC) of GA against Y. enterocolitica was determined by adopting the broth microdilution method. Second, an investigation was conducted on the morphological and physiological variations of Y. enterocolitica after the GA treatment. Finally, a response surface approach was used to establish the growth inhibition model of GA against Y. enterocolitica in pork. The MIC of GA against Yersinia enterocolitica BNCC 108930 was 2.5 mg/mL. GA affects the membrane integrity of Y. enterocolitica, as demonstrated by a significant decrease in intracellular ATP and pH. The results showed that the number of Y. enterocolitica in pork meat containing 5 mg/g of GA decreased by 2 logarithmic cycles during storage at 4 °C for 3 days. According to the obtained findings, GA could be used as a food preservative to prolong the shelf life of pork.

Fatty acids profile, antioxidant properties, phytosterols, induction period, and sensory characteristics of olein and super olein fractions of date seed oil

Date seed oil was cooled to −20°C, filtered to produce olein fraction (OF, yield 38%), olein was further cooled to −30°C to produce super olein fraction (SOF, yield 22%), kept in amber glass bottles at 25–30°C for 90 days. HPLC analysis showed that phenolic compounds were intensified in olein and super olein of date seed oil. In SOF, concentrations of chromatographic acid, quercetin, gallic acid, caffeic acid, chlorogenic acid, syringic acid, p-coumeric acid, m-coumeric acid, and ferulic acid were 26.11 mg/100 g, 245.61 mg/100 g, 23.72 mg/100 g, 115.19 mg/100 g, 133.42 mg/100 g, 18.74 mg/100 g, 83.25 mg/100 g, 53.47 mg/100 g, and 49.97 mg/100 g. The concentrations of C18:1 in date seed oil, olein, and super olein were 43.64%, 48.91%, and 55.37%, respectively. Total phenolic contents of date seed oil, olein, and super olein were 191, 295, and 343 mg GAE/100 g. At the end of storage, the peroxide value of date seed oil, olein, and super olein was 0.55, 0.71, and 0.85 (MeqO2/kg) with no difference in color, smell, and taste. Practical applications Increased information on nutrition- and health-associated disorders has a great influence on the development of functional foods. Unsaturated fatty acids, carotenoids, phytochemicals, and other bioactive compounds contained in vegetable oils have a large number of health benefits. Traditionally used vegetable oils are subjected to refining, bleaching, and deodorization to produce bland oils that lead to a complete elimination of almost all bioactive compounds. Date seed oil can be used in raw forms, and olein and super olein fractions of date seed oil were first time produced. Olein and super olein fractions had a higher concentration of unsaturated fatty acids, phenolic compounds than date seed oil with no difference in sensory characteristics. Olein and super olein fractions can be used in the development of the large number of functional foods.

Effect of Fermentation on the Bioactive Compounds of the Black Soybean and Their Anti-Alzheimer's Activity.

Black soybean is one of the nutritious crops and is being used in traditional medicines in Asian countries. In the present study, we fermented black soybean and screened against in vitro Alzheimer’s disease (AD) biomarkers such as cholinesterase enzymes, inflammatory factors, oxidative stress, and presence of γ-aminobutyric acid (GABA) levels. Firstly, we fermented black soybean with different lactic acid bacteria (LABs) and selected the Pediococcus acidilactici as the best LAB on the basis of GABA levels in the fermentate. We have found that black soybean fermented with P. acidilactici significantly inhibited the inflammatory factors (proteinase, protein denaturation, and lipoxygenase) and cholinesterase enzymes than non-fermented samples. An increase in the antioxidant capacity (FRAP, ABTS, and DPPH), anthocyanins, phenolics, flavonoids, and GABA content was also observed in fermented samples. Moreover, UHPLC-ESI-QTOF-MS/MS technique identified 38 bioactive components, including polyphenols, amino acids, and fatty acids. Among identified components, eight bioactive compounds were quantified, and an increase in the concentration of daidzein, genistein, glycitein, (+)-catechin, quercetin, and gallic acid was observed in fermented samples. However, the concentration of rutin and soyasaponin was higher in raw samples. These results indicated that fermentation of black soybean with P. acidilactici is a promising approach that can be used to develop functional foods to inhibit/prevent AD and other neurodegenerative diseases.

Enrichment of phenolic compounds from grape (Vitis vinifera L.) pomace extract using a macroporous resin and response surface methodology

A green protocol was proposed for the extraction and separation of high-value phenolic compounds (PCs) from grape (Vitis vinifera L.) pomace. The most important variables for scale-up purposes including extraction time (4–16 h), temperature (40–80 ℃), and solvent-to-feed ratio (8–40 mL.g−1) on the extraction efficiency and yield of PCs were scrutinized by experimental design using Response Surface Methodology (RSM). The yield of PCs was quantified by monitoring the content of gallic acid (GA) and procyanidin B using the HPLC-UV analysis. To obtain an enriched extract, the optimized extract was loaded on a new designed multi-stage continuous flow adsorption column filled with a nonionic acrylic polymeric resin (LXA-10) adsorbent. The adsorption properties, including the adsorption isotherms and kinetics as well as dynamic test in term of breakthrough curve analysis have also been investigated. The optimal extraction condition was attained at 80 °C, 10 h and 20 mL.g−1, and extraction efficiency of 10.67% w/w. After enrichment process, the purity of PCs in the resulting product was reached to 99%, and the yield of product respect to initial grape pomace powdered was 1.91%. These findings may have implications in the development of adjuvant supplement manufacturing with potential effect on improving immune system. Data AvailabilityThe authors confirm that the data used to support the findings of this study are included within the article and its Supplementary material.

Polyphenols in the Waste Water Produced during the Hydrodistillation of ‘Narcea Roses’ Cultivated in the Cibea River Valley (Northern Spain)

The ‘Narcea rose’ is a recently described yet ancient rose cultivar of interest to the perfume industry. Given its excellent adaptation to the conditions of the place where it was rediscovered, the possibilities of its horticultural/industrial production have been under examination for some time. The hydrodistillation process produces a red-to-brownish mixture of water and rose petals that could contain compounds that could be used in other industrial procedures. Their recovery and further utilization would reduce disposal costs and improve the sustainability of relevant industries. This work reports the quantification, by high-performance liquid chromatography (HPLC–MS) and quadrupole time of flight Q-TOF analyses, of the polyphenol content in the waste water. This waste was found to contain high concentrations of quercetin, gallic acid and ellagic acid, as well as smaller concentrations of kaempferol and its derivatives, all of which can influence plant, human and animal health.

Dietary behavior and urinary gallic acid concentration differences among underserved elder racial and ethnic minorities in New York City

PurposeDiet and nutrition are important for cancer prevention. To investigate associations between dietary behavior, demographics, and risk of cancer, we assessed dietary behavior and urinary concentration of gallic acid, a polyphenol with anticancer properties found in various fruits and vegetables, in racial and ethnic minorities.MethodsNinety-one (91) participants were recruited from senior centers in East Harlem, New York City, a racially diverse and underserved community. A National Institute of Health (NIH)—validated dietary survey questionnaire—was used to collect dietary fruits and vegetables consumption data. Demographic and cancer information were also collected. All 91 participants completed the survey and forty-five (45) participants provided urine samples for gallic acid analysis.ResultsGender differences were significantly associated with dietary behavior and urinary gallic acid concentration (UGAC). Female participants had a higher total daily intake of fruits and a significantly higher UGAC compared to male participants (p < 0.05). Age was negatively associated with the serving quantity of French fries/fried potatoes and white potatoes (p < 0.05), while positively associated with the daily intake frequency and daily intake of fruits (p < 0.05). Furthermore, Asian race was associated with higher daily intake frequencies of fruits and vegetable soup (p < 0.05), compared to other races. In a multivariate analysis, a significant association was observed between the serving quantities of fruits and other vegetables and UGAC (p < 0.05) after controlling for demographic characteristics.ConclusionThe observed differences in dietary behavior and UGAC in this study provide limited information on the association between demographic differences and cancer prevalence in elder racial and ethnic minorities. Future research should investigate this association further for potential implications in cancer prevention.

Study of Antioxidant Activity of Garden Blackberries (Rubus fruticosus L.) Extracts Obtained with Different Extraction Solvents

Blackberries are rich in antioxidants due to their high polyphenol and vitamin content, making them an excellent source of health protection. It is well known that good quality juices and fruit extracts can be obtained only from high quality fruits. The aim of this research is to characterize the antioxidant properties of garden blackberries fruits grown in Turia (Romania). Extracts were made from blackberry fruits with four different solvents, and the antioxidant capacity was studied by applying DPPH and FRAP assay. The total phenolic content (with Folin–Ciocâlteu reagent), total anthocyanin content (with the pH differential method), and total flavonoid content (with aluminum chloride colorimetric method) were also measured. The quercetin and gallic acid content were also determined by HPLC-DAD. As the best results were obtained with 90% v/v acidified acetonitrile, the Hansen parameters analysis was performed for the acetonitrile-water solvent mixture as a solvent and cyanidin-3-O-glucoside as a solute.

Chemical, Antioxidant, and Antimicrobial Properties of the Peel and Male Flower By-Products of Four Varieties of Punica granatum L. Cultivated in the Marche Region for Their Use in Cosmetic Products.

We are now seeing an increase in the production of agri-food waste, which is an essential resource for the recovery of bioactive compounds that may be employed as innovative natural ingredients in cosmetics. To date, the approach to cosmetics preservation has seen a significant shift in the search for biological components that give healthier alternatives for customers and help businesses operate in an environmentally friendly manner. To achieve this goal, we studied pomegranate extracts using the peel and, for the first time, extracts from the male flowers of a wide pomegranate variety cultivated in the Marche region, specifically, the Wonderful, Mollar de Elche, Parfianka, and less-studied G1 varieties. We studied the phenol compounds profile, antioxidant capacity, antimicrobial activity, and cell viability of the obtained pomegranate extracts. The identification and quantification of phenol compounds belonging to different classes, such as hydrolysable tannins, hydroxybenzoic acid, hydroxycinnamic acid, dihydroflavonol, gallocatechin, and anthocyanins, were performed using UPLC-ESI-MS/MS. Punicalagin isomers and punicalin resulted in the most abundant polyphenols found in the peel and male flower extracts. Mollar de Elche 2020 peel extract revealed a high concentration of punicalagin A and B (7206.4 mg/kg and 5812.9), while the content of gallic acid revealed high results in the G1 and Parfianka varieties. All extracts were spectrophotometrically analysed to determine their total phenol content (TPC) using the Folin–Ciocalteu method and their antioxidant capacity (AC). In terms of the total phenol obtained by the Folin–Ciocalteu colorimetric method, Mollar de Elche 2020 extracts reported the highest TPC content of 12.341 µmol GAE/g. Results revealed that the Mollar de Elche and Wonderful 2020 peel extracts demonstrated the highest TPC and AC. Furthermore, AC results indicated that the peel extracts displayed higher AC than the male flower extract due to the high punicalagin content detected by UPLC analysis. The antimicrobial activity testing revealed that the Wonderful and G1 2020 peel extracts resulted active against Escherichia coli, while all extracts exhibited promising anticandidal activity. Additionally, the cytocompatibility was evaluated in keratinocytes HaCaT cells by testing concentrations of pomegranate extracts ranging from 0.15 to 5.00 mg/mL. Extracts were non-toxic for the cells in the tested concentration range. The acquired results may help exploit pomegranate agri-food waste products provided by the Marche region’s short supply chain for their use as an antimicrobial and antioxidant booster in the formulation of cosmetic products.

Beware of the Potential Risks for Polygoni Multiflori Caulis-Induced Liver Injury.

Background: Reynoutria multiflora (Thunb.) Moldenke (PM) is a widely-used medicinal plant in China, whose root and stem are included in the Chinese Pharmacopoeia as Polygoni Multiflori Radix (RPM), Polygoni Multiflori Radix Preparata (PMP), and Polygoni Multiflori Caulis (PMC). The hepatotoxicity of RPM and PMP is concerned by the public, while the risk of PMC is ignored. Purpose: Here, we investigate the potential risks for PMC-induced liver injury from clinical, chemical, and animal features. Study design: First, we analyzed the 12-month usage of RPM, PMP, and PMC in Longhua Hospital. Second, we determined the contents of gallic acid, cis-2,3,5,4′-tetrahydroxy-stilbene-2-O-β-D-glucoside (cis-SG), trans-2,3,5,4′-tetrahydroxy-stilbene-2-O-β-D-glucoside (trans-SG), emodin-8-O-β-D-glucoside (EG), physcion-8-O-β-D-glucoside (PG), emodin, and physcion in the water extracts from 15 batches of RPM, PMP, and PMC. Third, we probed the hepatotoxic effect of RPM, PMP, and PMC in mice and explored the mechanism of cis-SG and trans-SG causing the liver injury at the dosages based on our results from the first and second parts. Results: PMC had nearly five times the amount of usage in both outpatient prescriptions and inpatient orders than RPM and PMP. Overall, 68% dosage of PMC was 30 g. The contents of cis-SG, trans-SG, and emodin in PMC water extracts were significantly lower than those in RPM and PMP water extracts. PMC induced milder idiosyncratic liver injury for its lower content of cis-SG and trans-SG than its root counterparts. Conclusion: The potential risks for PMC-induced liver injury should be fully aware of.

Impact of Different Drying Temperatures onIn VitroAntioxidant and Antidiabetic Activities and Phenolic Compounds of Wild Guava Leaves Collected in the Central Highland of Vietnam

Most biologically natural compounds are very sensitive and easily degradable under drying conditions. This study aimed to investigate the effect of drying temperature on the contents of phenolic compounds and in vitro antioxidant and antidiabetic activities of wild guava leaves. Wild guava leaves were dried at 40 °C, 50 °C, 60 °C, 70 °C, and 80 °C, as well as sun drying (SD). The total phenolic and flavonoid contents (TPC and TFC) were measured using the colorimetric method. Antioxidant activity was determined by the 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) and 2,2-azino-bis(3-ethylbenzothazoline-6-sulfonic acid (ABTS) radical scavenging activity assays. In vitro antidiabetic activity was measured by assessing α-glucosidase and α-amylase inhibitory activities. The contents of individual phenolic compounds were determined using ultra-performance liquid chromatography (UPLC). The principal component analysis (PCA) results revealed that hot air drying at different temperatures had significantly different effects on the bioactive compounds and biological properties of guava leaves. Drying at high or low temperatures resulted in a higher degradable rate of bioactive compounds leading to a weakening of the biological properties. Drying at 50 °C resulted in high TPC and TFC as well as the highest in vitro antioxidant and antidiabetic activities. Furthermore, the highest contents of gallic acid, catechin, rutin, quercetin, apigenin, quercitrin, vitexin, and apigenin-7- O-D-glucopyranoside were found in samples dried at 50 °C, whereas the highest contents of chlorogenic acid, epicatechin, and ellagic acid were observed in samples dried at 60 °C. Therefore, drying at 50 °C was the suitable temperature for retaining valuable biological compounds in wild guava leaves.

Impact of kernel development on phenolic profiles and antioxidant activity in Castanea henryi

SummaryThe changes in the phenolic profiles during the kernel development of two varieties of Castanea henryi (‘Jinzhui’ (YS) and ‘Baiyan No.1’ (WS)) were investigated based on content levels and gene expression levels. The results showed that the total phenolic content (TPC) increased during the Castanea henryi development and were mainly dependent on the content variation of gallic acid and (‐)‐epicatechin. Gene C4H positively affected the accumulation of p‐coumaric acid, while gene CHI and F3H positively affected the biosynthesis of (‐)‐epicatechin. Four assays including DPPH, FRAP, ABTS and ORAC were conducted to evaluate the antioxidant quality of Castanea henryi extracts. The results showed that the Castanea henryi developed at S4 (stage 4) possessed the better antioxidant quality. In addition, in both varieties, FRAP and ORAC value were more likely to be influenced by the variation of gallic acid and (‐)‐epicatechin concentrations, respectively. The DPPH value in YS was dependent on the syringic acid and the gallic acid content in WS.

Influence of Different Defoliation Timings on Quality and Phenolic Composition of the Wines Produced from the Serbian Autochthonous Variety Prokupac (Vitis vinifera L.)

The variety Prokupac is the dominant variety in the vineyards of Southern Serbia, which produces quality wines of characteristic and unique tastes. In the agroecological conditions of the Prokuplje vine district, the influence of manual defoliation on the phenolic profile of the wine produced from the variety Prokupac was examined. Four experimental treatments with different timings of manual defoliation were applied: early defoliation—treatment I, early defoliation—treatment II, late defoliation—treatment III and the control. The phenolic profile of the wine was determined for the three treatments of defoliation and the control treatment. Additionally, a multivariate analysis was applied on the obtained results, together with already published data (grape seeds and skins phenolic profiles). Identification and quantification of the phenolic compounds was performed using ultra-high-performance liquid chromatography (UHPLC) with an ultraviolet multi-diode detector (DAD) and mass detector with three analyzers—triple quadrupole (QQQ). Based on the obtained results, it was determined that there are significant differences between the experimental treatments in the content of individual polyphenols, total polyphenols and the antioxidant capacity. Twenty (20) phenolic compounds were identified in the wine samples of the experimental treatments. Defoliation significantly affected the variations of the contents of phenolic acids and flavonoids. In treatment III, the highest content of gallic acid was obtained, while the treatments with early defoliation did not differ in relation to the control sample. Early defoliation in treatments I and II had an effect on the phenolic composition of the wine by favoring the accumulation of flavonol, while the content of hydroxycinnamic acid and total anthocyanins (TAC) was higher in treatment III. The TAC increases with later defoliation. The wines obtained by the defoliation treatments did not show higher antioxidant activity compared to the control sample. A principal component analysis resulted in clustering of the samples based on the phenolic components characteristic for each group of samples.

Bovine serum albumin with gallic acid: Molecular modeling and physicochemical profiling

Introduction. Gallic acid is a biologically active natural compound with strong antioxidant properties. Gallic acid is highly soluble and stable. It is known to increase the thermal stability of protein. However, its bioavailability is low, but interaction with proteins can solve this problem. Bovine serum albumin can bind various ligands, including polyphenols. The resulting complex of gallic acid and bovine serum albumin can become a promising functional food additive.&#x0D; Study objects and methods. This research featured in silico molecular modeling of gallic acid and bovine serum albumin using the HyperChem program. The methods of infrared spectrometry, potentiometry, and sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) made it possible to describe the physicochemical profile of the complex.&#x0D; Results and discussion. The molecular modeling confirmed that hydrophobic interactions were responsible for the chemical bond between gallic acid and bovine serum albumin. The SDS-PAGE test showed that the protein molecule remained intact. The reducing properties of the complex grew as the concentration of gallic acid increased. At 100 mg/L of gallic acid, the reducing properties were 7.8 ± 1.3 mg/L equivalent of gallic acid. At 200 and 300 mg/L, the values reached 15.90 ± 2.65 and 23.30 ± 5.05 mg/L, respectively. The IR spectrometry revealed a significant difference between the samples with different concentrations of gallic acid.&#x0D; Conclusion. The research managed to predict the properties of the complex of bovine serum albumin and gallic acid during its formation. The resulting complex had the highest reducing properties at 0.69 g of bovine serum albumin and 300 mg of gallic acid. The obtained parameters can be used in the food industry to develop new food additives.

Analysis of Plant Growth and Gallic Acid Content for Cavendish Banana (Musa acuminata) Shoot Culture with Bubble Column Bioreactor

Cavendish banana (Musa acuminata) is one of the most important fruits in the world. Cavendish shoots tissue culture using bubble column bioreactor can be a solution to produce high yielding plantlet and gallic acid due to the aeration with minimum shear stress. In this study, the average growth rate, presence of gallic acid, and antioxidant activity (IC50) in the bubble column bioreactor (200 mL capacity) with the aeration rates of 1 mL/s and 2 mL/s using Murashige &amp; Skoog half-strength liquid medium supplemented with 0.5 ppm gibberellic acid will be analyzed. The aeration system used was atmospheric air. The leaves and stems were extracted by maceration using 96% ethanol solvent (1:10 (w/v)). A qualitative phenolic test with FeCl3, thin layer chromatography, and antioxidant test with 2,2-diphenyl-1-picrylhydrazyl was carried out. The average growth rate in the bioreactor were 0.22 ± 0.001 g/day (1 mL/s) and 0.21 ± 0.001 g/day (2 mL/s). All the leaf and stem extracts showed positive results for the phenolic test, but the presence of gallic acid could not be detected clearly by thin-layer chromatography. The IC50 values in aeration rates of 1 mL/s and 2 mL/s of the leaves were 41.35 and 79.54 μg/mL, respectively, while the stems were 51.87 and 104.94 μg/mL, respectively. It could be concluded that the growth of the banana plantlet and the production of antioxidants in the bubble column bioreactor was higher in aeration rate of 1 mL/s than 2 mL/s.

A simple and efficient electrochemical sensor for determination of gallic acid based on multi-walled carbon nanotubes with carboxyl functionalization

ABSTRACT We designed a simple and efficient electrochemical sensor for the determination of gallic acid (GA) by modifying the glassy carbon electrode (GCE) with the carboxyl-group functionalized multi-walled carbon nanotubes (MWCNTs-COOH). For this kind of carbon nanomaterial, MWCNTs-COOH possessed good electrical conductivity and enough specific surface area due to the one-dimensional hollow carbon skeleton with high charge transfer efficiency. Moreover, the carboxyl functionalization of MWCNTs-COOH could promote the homogeneous dispersion of multi-walled carbon nanotubes due to the enhanced surface wettability of carboxyl groups, which helped provide larger electrochemical active surface area and more efficient electron transport channels. Based on the above advantages, the fabricated MWCNTs-COOH/GCE sensor showed a low limit of detection of 0.0067 μM in the linear GA concentration range of 0.01-10 μM. In addition, the good reproducibility, repeatability, stability, and selectivity could be obtained at the fabricated sensor.

The modification of pomegranate polyphenol with ultrasound improves mechanical, antioxidant, and antibacterial properties of tuna skin collagen-chitosan film

To produce an edible film with high mechanical and physicochemical properties, Tuna skin collagen-chitosan (TSC-CTS) composite films were prepared by incorporating ultrasound (UT) and pomegranate polyphenols including gallic acid (GA), tannic acid (TA), and ellagic acid (EA), respectively. The tensile strength and the DPPH scavenging activity of the GA-UT-TSC-CTS film (ultrasound frequency of 28 ± 0.5 kHz, power of 100 W/L, sweep frequency cycle of 100 ms, duty ratio of 77% and time of 10 min; GA concentration of 1.0 g/L and reaction time of 10 min) were increased by 47.03% and 24.16 folds, respectively compared to the control (TSC-CTS film). Meanwhile, light transmittance and water vapor permeability of the GA-UT-TSC-CTS film were decreased by 29.26% and 15.70%, respectively. These positive modification results were attributed to the altered structure during the film formation process, which were verified by Fourier transform infrared spectroscopy (FTIR), circular dichroism (CD), X-ray diffraction (XRD), and thermogravimetry results. Moreover, the GA-UT-TSC-CTS film possessed moderate thermal stability and color indexes and improved antibacterial activity. The antibacterial effect of the film against Bacillus subtilis was the highest, followed by Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus. Overall, the combination modification of gallic acid and ultrasound was an efficient modification method to improve the mechanical, antioxidant, and antibacterial properties of edible TSC-CTS films.

Does u.v. light affect the total phenolic compound, anthocyanin, antioxidant capacity, and sensory profiles in wines?

SummaryIn the study, by applying ultraviolet (u.v.) lights (254 nm) for 45 min to red wines from fermented Cabernet Franc, Cabernet Sauvignon, Merlot, and Petit Verdot (Vitis vinifera L.) grapes, we examined the total phenolic compound, total anthocyanin, and antioxidant capacity by four different methods, trans‐resveratrol, (+)‐catechin, gallic acid content, and the change in tasting profiles of the wines after application. According to the results of the research, the u.v.‐C application has caused an increase in all parameters examined. If we talk about averages without distinguishing between varieties, after the application the total phenolic compound content of 3206 increased to 3356 mg gallic acid equivalent (GAE) per L and after u.v.‐C application, the total anthocyanin content increased from 411 to 780 mg L−1, the ABTS [2,2′‐azinobis(3‐ethyl‐benzothiazoline‐6‐sulphonic acid)] value increased from 30 to 33 μmol trolox mL−1, the DPPH ((2,2‐diphenyl‐1‐picrylhydrazyl) level increased from 13 to 16 μmol trolox mL−1, the FRAP (ferric reducing antioxidant power) level increased from 15 to 16 μmol trolox mL−1, and the CUPRAC (cupric reducing antioxidant capacity) level increased from 40 to 45 μmol trolox mL−1. The u.v. application affected trans‐resveratrol the most among the phenolic compounds and an average increase of 12.99% was obtained. The rate of increase after u.v. application was 3.33% in (+)‐catechin and 5.57% in gallic acid. The highest correlation between antioxidant activity measurement methods was measured to be 0.998 between FRAP and DPPH. In addition, u.v.‐C application has had a positive effect on taste‐based sensory profiles. In recent years, the search for a diet with a high antioxidant content has become even more important.

Natural Control of Weed Invasions in Hyper-Arid Arable Farms: Allelopathic Potential Effect of Conocarpus erectus against Common Weeds and Vegetables

Utilization of plant allelopathic potential to control weed infestations provides an effective, cost-efficient, labor-free, and environmentally acceptable alternative to traditional chemical and mechanical methods. Conocarpus erectus, known as buttonwood, belongs to the Combretaceae family with high contents of phytochemicals and antioxidant activity. There have been no studies on the allelopathic potential of C. erectus. The present study (1) examined the allelopathic potential of C. erectus against selected weeds (Chenopodium murale and Amaranthus viridis) and crops (Solanum lycopersicum and Cucumis sativus) via investigating the growth inhibition ability of its aqueous extract, and (2) identified the potential allelochemicals found in this plant. Aqueous extracts were prepared from leaves, roots, and seeds of C. erectus by immersing the dried powder of the examined plant parts in sterile distilled water for 24 h on a shaker set to 180 rpm. The resulting filtrate was considered as 100% solution, and then dilutions were made to various concentrations (75%, 50%, and 25%). C. erectus leaves and seeds showed the highest rate of inhibition at all concentrations against Chenopodium murale and Amaranthus viridis grown in either Petri dishes or pots. Conversely, all the studied extracts did not show any toxic effects against tomato and cucumber plants grown in pots. In Petri dishes, a slight reduction in growth was observed. HPLC analysis of total phenolic contents in C. erectus methanolic extracts showed that leaves have the highest contents of gallic acid, caffeic acid, and ferulic acid (153.963, 69.135, and 39.801 ppm, respectively). The finding of the current study demonstrated that the part of the plant and the concentration of extraction have a significant effect on phytotoxicity. The positive results of this study might be used to develop environmentally-friendly herbicides for agricultural purposes.

Determination of dioecy in Hippophae salicifolia by evaluating gallic acid content through a validated HPTLC method

Determination of dioecy in Hippophae salicifolia by evaluating gallic acid content through a validated HPTLC method

Collagen/zein electrospun films incorporated with gallic acid for tilapia (Oreochromis niloticus) muscle preservation

The aim of this study was to develop a collagen (Col)/zein (ZN) electrospun film encapsulated with different concentrations of gallic acid (GA), using electrospinning, for the preservation of tilapia muscle. The microscopic morphology of all collagen/zein/gallic acid (Col/ZN/GA) electrospun films, which exhibited average diameters ranging from 272 to 384 nm, were smooth and contained no beads. GA was well distributed and incorporated into the protein matrix and formed hydrogen bonds. The addition of GA caused a reduction in hydrophobicity but markedly increased the antioxidant activity of the Col/ZN/GA electrospun films. The preservation assay showed that the Col/ZN/GA electrospun films containing 8% (w/w) gallic acid (GA8) significantly (P＜0.05) halted tilapia muscle quality deterioration and prolonged the shelf life of fish muscle for at least two days. Therefore, the GA8 electrospun films have potential as active food packaging materials to extend shelf life of fresh tilapia muscle and may have good application prospect in the fish filleting industry.