Levels Of Total Phenolic Compounds Research Articles

Optimization of Microwave-Assisted Extraction of Polyphenols from Lemon Myrtle: Comparison of Modern and Conventional Extraction Techniques Based on Bioactivity and Total Polyphenols in Dry Extracts

The aromatic herb lemon myrtle is a good source of polyphenols, with high antioxidant and antimicrobial capacity. In this study, the green extraction technique microwave-assisted extraction (MAE) was applied and the extraction parameters were optimized using response surface methodology (RSM) to maximize the extraction yield of phenolic compound and antioxidant properties. Then, it was compared with other popular novel and conventional extraction techniques including ultrasound-assisted extraction (UAE) and shaking water bath (SWB) to identify the most effective technique for extraction of phenolic compounds from lemon myrtle. The results showed that the MAE parameters including radiation time, power, and sample to solvent ratio had a significant influence on the extraction yield of phenolic compounds and antioxidant capacity. The optimal MAE conditions were radiation time of 6 min, microwave power of 630 W, and sample to solvent ratio of 6 g/100 mL. Under optimal conditions, MAE dry extract had similar levels of total phenolic compounds (406.67 ± 8.57 mg GAE/g DW), flavonoids (384.57 ± 2.74 mg CE/g DW), proanthocyanidins (336.54 ± 7.09 mg CE/g DW), antioxidant properties, and antibacterial properties against (Staphylococcus lugdunensis and Bacillus cereus) with the other two methods. However, MAE is eight-times quicker and requires six-times less solvent volume as compared to UAE and SWB. Therefore, MAE is recommended for the extraction of polyphenols from lemon myrtle leaf.

Sustainable fermentation approach for biogenic hydrogen productivity from delignified sugarcane bagasse

Improper lignocellulosic wastes management causes severe environmental pollution and health damage. Conversion of such wastes particularly sugarcane bagasse (SCB) onto bioenergy is a sustainable approach due to a continuous depletion of conventional biofuels. The delignification of SCB is necessary to proceed for bio-genic H2 productivity by anaerobic bacteria. The effect of autoclaving, pre-acidification/autoclaving and pre-alkalization/autoclaving of SCB on glucose recovery and subsequently H2 productivity by dark fermentation was comprehensively investigated. Pre-acidified SCB with 1% H2SO4 (v/v) provided H2 productivity of 8.5 ± 0.14 L/kg SCB and maximum H2 production rate (Rm) of 105.9 ± 8.3 mL/h. Those values were dropped to 2.7 ± 0.13 L/kg SCB and 58.3 ± 12.9 mL/h for fermentation of delignified SCB with 2% H2SO4. This was linked to high levels of total phenolic compounds (1775.3 ± 212 mg/L) in the feedstock. Better H2 productivity of 13.9 ± 0.58 L/kg SCB and Rm of 133.9 ± 3.6 mL/h was achieved from fermentation of pre-alkalized SCB with 1%KOH (v/v). 256.8 ± 9.8 U/100 mL of α-amylase, 165.7 ± 7.6 U/100 mL of xylanase, 232.8 ± 6.1 U/100 mL of CM-Cellulase, 176.5 ± 5.0 U/100 mL of polyglacturanase and 0.702 ± 0.013 mg M B. reduced/min. of hydrogenase enzyme was accounted for the batches supplied with delignified SCB by KOH. The Clostridium and Bacillus spp. was dominance and prevalence resulting a higher H2 productivity and yield. A novel strain of Archea and alpha proteobacterium were also identified and detected.

Influence of pretreatments combined with extrusion on γ-amino butyric acid, nutritional composition and physicochemical properties of foxtail millet (Setaria italica)

Extrusion processing deals with a compromise between better texture and less nutrition. Therefore, present study was conducted to assess the combine effect of pretreatments (germination, fermentation and sonication) and extrusion on γ-amino butyric acid (GABA), total phenolic content, antioxidant activity and physicochemical properties of foxtail millet. The GABA content significantly (P < 0.05) increased in pretreated extrudates whereas highest content was revealed in germinated millet extrudates (7.24 mg/100 g) followed by germinated-sonicated millet extrudates (6.15mg/100 g) as compared to native millet extrudates and native millet flour. Pretreated extrudates maintained higher total phenolic compounds (TPC) and antioxidant activity than native millet extrudates. Among pretreated extrudates, germinated millet extrudates retained highest level of TPC (30.54 mg GAE/g), DPPH scavenging activity (15.51%) and ABTS (2.97 mg Trolox E/g). Moreover, oleic acid, palmitic acid and linolenic acid were increased, while linoleic acid content decreased in pretreated extrudates. Additionally, pretreated extrudates had higher water absorption and solubility index, while lower bulk density was recorded as compared to native millet extrudates. Extrudates obtained from pretreated millet under optimum conditions improved nutritional, functional and physiochemical characteristic. Therefore, this approach may help food industries to develop gluten free and healthy extrudates by incorporating pretreated foxtail millet in human diet.

Dietary Phytochemical Screening of Spider Plant (Gynandropsis gynandra (L.) Briq.) Accessions From Africa and Asia to Identify Genotypes for Use in Nutraceutical Breeding

Increased public awareness of healthy foods and healthy living, coupled with escalating medicinal costs and recent advances in research and technology, has sparked a paradigm shift to nutraceuticals, which guarantee human health and disease prevention. Spider plant (Gynandropsis gynandra) contains dietary phytochemicals with high nutritional and medicinal properties that can contribute to healthy living. A study was conducted to identify spider plant (Gynandropsis gynandra(L.) Briq.) accessions with superior levels of dietary phytochemicals and anti-oxidative activity for use in nutraceutical breeding. Thirty-three accessions of spider plant, representing a wide genetic diversity based on geographic areas of origin (Asia, East Africa, Southern Africa, and West Africa), were used. Total phenolic acids, tannins, and anthocyanins were extracted and quantified using the Folin-Ciocalteau colorimetric, spectrophotometric, and pH differential methods, respectively. Antioxidant activity was determined using phosphomolybdenum method. Results showed significant variation in levels of total phenolic compounds, tannins, anthocyanins, and antioxidant activity (P&amp;lt; 0.05) amongst the spider plant accessions and regions of origin; ODS-15-037 (464 mg TAE/g DW), ODS-15-053 (270 mg GAE/g DW), and BC-02A (127 mg cyanidin-3-glucoside/g DW) had the highest levels of total tannins, phenolic compounds, and anthocyanins, respectively. Antioxidant activity was high in ODS-15-053 (492.2 mg AAE/100 g DW), NAM 2232 (445.3 mg AAE/100 g DW), and NAM-6 (432.5 mg AAE/100 g DW). On average, West African accessions had significantly high tannin concentrations (239 mg TAE/g DW), while Southern Africa accessions contained significantly high anthocyanin content (58.9 mg cyanidin-3-glucoside/g DW). The superior accessions are potential candidates for use in nutraceutical breeding, while the regions of origin could be used as gene pools for specific phytochemicals for improving dietary supplements of nutraceuticals. The strong antioxidant activity exhibited by spider plant accessions suggests the presence of compounds responsible for scavenging free oxygen or nitrogen radicals. Further studies are recommended to identify the chromosomal regions that contain genes controlling the dietary nutraceuticals in the genetic materials and to determine their association with foliage yield and other phenotypes, which can be utilized in spider plant improvement.

Metabolite profiling and antioxidant capacity of lettuce Lactuca sativa var. longifolia grown in aquaponic system irrigated with shrimp effluents

This paper focuses on the quality of lettuce var. longifolia grown with shrimp effluents from well water (WW), diluted seawater (DSW) and a hydroponic solution (HS). Results evidenced that WW and DSW effluents slightly decreased weight, foliage, and yield (5-9%) in plants compared to HS control. Furthermore, WW-lettuce showed a higher level of total phenolic compounds (~71%), flavonoids (~90%), and antioxidant capacity (0.7-3-folds) than HS-plants, mainly in the soluble fraction. WW-lettuce also showed a higher content of total soluble solids (~16%) and, a lower saturation of color, which correlated significantly (p &lt;0.05) with chlorophyll a. WW-lettuce exhibited the highest concentrations of p-hydroxybenzoic, p-coumaric and ferulic acids, as well as quercetin 3-O-glucoside and quercetin 3-O-ramnoside. Whereas DSW-lettuce showed the highest levels of caffeic acid, isorhamnetin 3-O-glucoside, kaempferol 3-O-glucoside, kaempferol and quercetin. HS-lettuce showed a higher proline content than the lettuces from the other treatments. These results indicate that aquaponic lettuce culture with shrimp effluent from WW could be used as an alternative culture system to reduce land area requirements, decrease or eliminate the discharge and impact of shrimp effluents, and simultaneously improve the functional properties of lettuce.

Changes in the bioactive compounds and antioxidant activity in red-fleshed dragon fruit during its development

Red-fleshed dragon fruit (Hylocereus polyrhizus) is a promising food with a functional appeal. This study investigated the changes in the bioactive compounds and antioxidant activity of the red-fleshed dragon fruit at eight development stages. In general, the levels of total phenolic compounds tested using Folin-Ciocalteu, and Fast Blue BB reagents, betacyanin, betaxanthin, anthocyanins, and antioxidant activity by TEAC, FRAP, and ß-carotene bleaching increased over the fruit development stages, whereas vitamin C content significantly decreased. Six phenolic compounds were identified, including catechin, vanillin, gallic acid, caffeic acid, chlorogenic acid, and ferulic acid. Catechin was the majority compound, followed by vanillin. All these compounds decreased during fruit development; chlorogenic and ferulic acids were only detected 30 days after anthesis. Based on the results, the suitable harvest period of red-fleshed dragon fruit is between 36 and 38 days after anthesis.

Reducing the Negative Effect on White Wine Chromatic Characteristics Due to the Oxygen Exposure during Transportation by the Deoxygenation Process.

In white wine production, a great effort is made to avoid extensive contact with oxygen, which might adversely affect color and aroma. In this work, the impact of bulk transportation on white wine oxygen uptake and the effect of deoxygenation on white wine dissolved oxygen levels, as well on the phenolic composition and chromatic characteristics of white wines stored for nine months, were studied. Transportation increased the white wine dissolved oxygen content (117 and 181% in the wines studied) that increased the free sulfur dioxide loss during storage. Moreover, deoxygenation of white wines reduced the increase in the yellow color of white wines during storage, probably related to the higher levels of free sulfur dioxide that remain in these wines during storage. Furthermore, the amount of wine phenolics also have a decisive influence on wine color characteristics evolution, with increased levels of total phenolic compounds increasing the variation in the b *(measure of yellowness) values of the wines after nine months of storage. Results show the negative impact of bulk transportation on white wine color characteristics; however, wine deoxygenation is a good practice to minimize those aspects, preserving color characteristics.

Edible seeds clustering based on phenolics and antioxidant activity using multivariate analysis

Edible seeds, especially those known by the population as nuts, have their consumption associated with functional appeal. The present study aimed to compare and group nine different seeds, traditional and regional, according to their similarities, in terms of moisture, total phenolic compounds (TPC) and antioxidant activity, through multivariate analyses. All results were submitted to Principal Component Analysis (PCA), Hierarchical Clusters (HCA) and Kohonen's self-organizing maps (ANN/KSOM). The seeds differed in terms of moisture content, TPC and antioxidant activity. The walnut butterfly stood out with the highest levels of TPC and antioxidant activity. In the multivariate analyses application, three groups were formed: i) hazel, baru, Brazil, macadamia, almond and cashew; ii) pequi and marolo; iii) walnut butterfly. It is concluded that the seeds can be separated into three groups, with ANN/KSOMs being the most self-explanatory analysis and that regional seeds are nutritionally similar to those traditionally consumed.

Impact of Specialty Malts on Wort and Beer Characteristics

Specialty malts are commonly used in brewing to provide flavor, aroma, and color to wort and beer. The use of specialty malts contributes to the variety of beer products; therefore, it is important to understand their effect on the characteristics of wort and beer. This study investigates the impact of various specialty malts on wort and beer properties. A control beer was prepared with 100% base malt, and four beer treatments were prepared with the addition of kilned, roasted, and caramel specialty malts. For each treatment, 20% of the base malt was substituted with the various specialty malts when preparing the wort. The fermentable sugars and free amino nitrogen (FAN) content for each wort were analyzed. Alcohol by volume (ABV), international bitterness units (IBU), diacetyl, and polyphenol content of each prepared beers were subsequently analyzed. Results showed that wort prepared with the addition of roasted and caramel malts contained a lower concentration of fermentable sugars and FAN than wort prepared with the base and kilned malts. Beers prepared with the addition of roasted and caramel malts exhibited the lowest levels of ABV, as well as the lowest levels of diacetyl. These beers also exhibited higher levels of total phenolic compounds compared to the other beer samples. No change was observed in IBU levels as a result of brewing with the different specialty malts. This study illustrates how the use of specialty malts impacts wort and beer properties, providing useful information to aid in the production of quality beer products.

Soybean β-conglycinin and catfish cutaneous mucous p22 glycoproteins deteriorate sporangial cell walls of Pseudoperonospora cubensis and suppress cucumber downy mildew.

Cucumber plants suffer from a serious threatening disease, downy mildew, throughout the growing seasons irrespective of the weather temperature. The causal agent, Pseudoperonospora cubensis, tends to evolve rapidly upon sequential applications of chemical fungicides and generate new progeny possessing tolerance to such fungicides. Glycoproteins represent an environmentally safe alternative for chemically synthetized fungicides and do not trigger fungicide resistance. We studied the antifungal activity of four glycoproteins namely soybean β-conglycinin, chickpea vicilin, duck egg ovomucin and catfish p22 against P. cubensis. Ten commercial fungicides of different chemical groups were used as positive controls of glycoprotein treatments. The results revealed that soybean β-conglycinin and catfish p22 glycoproteins possess significant antifungal activity against P. cubensis. The amount of disease suppression caused by β-conglycinin and p22 was comparable to the highly efficient chemical fungicides containing copper oxychloride, cymoxanil and fosetyl Al as active ingredients. Vicilin and ovomucin were less efficient biocides as they gave moderate suppression of disease severity. However, all tested glycoproteins provided full protection for the newly emerged cucumber leaves. Microscopic examination of glycoprotein-treated leaves inferred the ability of catfish p22 and soybean β-conglycinin to disrupt the integrity of sporangial cell walls of P. cubensis rendering them non-viable compared to untreated ones. Expression levels of total phenolic compounds and the antioxidant enzymes catalase, superoxide dismutase and peroxidase were elevated upon glycoproteins application, which infers their involvement in disease suppression. This report emphasizes the direct and indirect roles of glycoproteins in safe management of cucumber downy mildew disease. © 2021 Society of Chemical Industry.

Vegetative propagation, chemical composition and antioxidant activity of yerba mate genotypes

AbstractIlex paraguariensis, commonly known as yerba mate, is a tree species native to South America. Its commercial value is due to the manufacturing of teas, with potential also in the pharmacological and cosmetic industries. Vegetative propagation of yerba mate is considered an innovation to the traditional production systems based on sexual propagation. The present study aimed to evaluate the rhizogenic potential and chemical attributes of mini-cuttings from 15 yerba mate genotypes, as well as to verify the correlation between phytochemical and rooting-related variables. Mini-cuttings were collected from a pre-existing mini-clonal hedge and the experimental design was completely randomized, with 15 treatments (genotypes), four replications and 10 mini-cuttings per plot. After 120 days, mini-cuttings were assessed regarding rooting, mortality, callogenesis and leaf retention percentages, percentage of mini-cuttings with both calluses and roots, number of roots and average root length. At the time of collection, subsamples from each plot were used for phytochemical analyses including total phenolic compounds, protein, caffeine and theobromine contents and antioxidant activity. Rooting percentages ranged from 5 to 72.5%, with significant variation among genotypes. Adventitious rooting and phytochemical profile of yerba mate mini-cuttings are genotype-dependent. Leaf retention is a relevant factor in the rooting of yerba mate mini-cuttings and the levels of total phenolic compounds, antioxidants and theobromine present in mini-cuttings are negatively correlated components toIlex paraguariensisadventitious rooting.

Evaluation of effect of different solvent systems on functional and pharmacological properties of fruits and leaves extracts from natal plum

This study appraises functional and pharmacological attributes and phenolic bioactive compounds profile of various solvent (distilled H2O, 50% C2H5OH, 100% n-hexane, 100% ethyl acetate, 100% CH3OH, 100% chloroform) extracts from fruits and leaves of Natal plum (Carissa grandiflora). The antioxidant activity of the extracts was analyzed by the determinations of total flavonoid contents, total phenolic contents, DPPH radical scavenging capacity and ferric reducing antioxidant power assay. Additionally, anti-inflammatory, anti-cancer, anti-bacterial and individual phenolics composition of the tested extracts were also investigated. The experimental results revealed that the highest percent bioactive compounds extract yield (35.01%) was obtained from fruits with 50% distilled water while lowest (7.2%) from leaves with chloroform. The tested fruit extracts exhibited better antioxidant activity as compared to leaves extracts. Total phenolic and total flavonoid contents in various solvents extracts of fruit and leaves varied from 8.7–143.08, 3.1–96.02 GAE (mg/g) and 6.52–62, 3.6–28.84 CE DW (mg/g) while the levels of total individual phenolic compounds, identified by High Performance Liquid Chromatography, were 400–3500 and 600–4500 mg/g, respectively. Pure (100%) methanolic extract from leaves showed highest activity (10.11 mm inhibition zone diameter) against B. subtilis whereas 50% ethanolic extract from fruits was most potent (8.56 mm) against E. coli. In case of anti-inflammatory activity, 100% CH3OH extract from leaves showed better activity followed by 100% ethyl acetate extract. The high anticancer activity was displayed by 100% chloroform extract from fruits (percent inhibition 89.16%; IC50 2.4 ± 0.09) against MCF-7 cell lines in MTT colorimetric assay. The solvents polarity-based differences were observed in terms of quantifiable yield and activities of the extracted bioactive compounds. In the light of present results, methanol and chloroform extracts from fruits and leaves of natal plum can be explored as potential sources of potent bioactive compounds for nutra-pharmaceutical developments.

Pichia galeiformis Induces Resistance in Postharvest Citrus by Activating the Phenylpropanoid Biosynthesis Pathway.

This study aimed to investigate the effect of Pichia galeiformis on disease resistance and elucidate the changes in phenylpropane biosynthesis treated by P. galeiformis in postharvest citrus. The results showed that P. galeiformis reduced the disease incidence and lesion diameters without direct contact with the pathogen Penicillium digitatum. Transcriptome analysis revealed that phenylpropanoid biosynthesis was triggered by P. galeiformis. Genes encoding phenylpropanoid biosynthesis were upregulated, including phenylalanine ammonia-lyase (PAL), 4-coumaroyl-CoA ligase (4CL), cinnamate-4-hydroxylase (C4H), peroxidase (POD), cinnamyl alcohol dehydrogenase (CAD), O-methyltransferase, and hydroxyl cinnamoyl transferase. Moreover, P. galeiformis increased the activity of PAL, 4CL, C4H, POD, polyphenol oxidase, and CAD in citrus pericarp. In addition, P. galeiformis treated citrus displayed higher levels of total phenolic compounds, flavonoid, and lignin and higher amounts of ferulic and sinapic acid. In conclusion, these results suggested that P. galeiformis could induce resistance through modulating the pathway of phenylpropanoid biosynthesis in postharvest citrus.

Melatonin alleviates drought impact on growth and essential oil yield of lemon verbena by enhancing antioxidant responses, mineral balance, and abscisic acid content.

Melatonin has recently emerged as a multifunctional biomolecule with promising aspects in plant stress tolerance. The present study examined the effects of foliar-sprayed melatonin (0, 100, and 200 μM) on growth and essential oil yield attributes of lemon verbena (Lippia citriodora) under water-shortage (mild, moderate and severe). Results revealed that melatonin minimized drought effects on lemon verbena, resulting in improved growth and essential oils yield. Drought impositions gradually and significantly reduced several growth parameters, such as plant height and biomass, whereas melatonin application revived the growth performance of lemon verbena. Melatonin protected the photosynthetic pigments and helped maintain the mineral balance at all levels of drought. Melatonin stimulated the accumulation of proline, soluble sugars and abscisic acid, which were positively correlated with a better preservation of leaf water status in drought-stressed plants. Melatonin also prevented oxidative damages by enhancing the superoxide dismutase, ascorbate peroxidase and catalase activities. Furthermore, increased levels of total phenolic compounds, chicoric acid, caffeic acid and chlorogenic acid, as well as ascorbate and total antioxidant capacity in melatonin-sprayed drought-stressed plants indicated that melatonin helped verbena plants to sustain antioxidant and medicinal properties during drought. Finally, melatonin treatments upheld the concentrations and yield of essential oils in the leaves of lemon verbena regardless of drought severities. These results provided new insights into melatonin-mediated drought tolerance in lemon verbena, and this strategy could be implemented for the successful cultivation of lemon verbena, and perhaps other medicinal plants, in drought-prone areas worldwide.

Antibiotic resistance profile of gram-negative bacteria isolated from dog nasal swab samples, and antibacterial and antioxidant activities of aqueous extracts of Alpinia purpurta (Vieill.) K. Schum (Zingiberaceae)

The indiscriminate use of antibiotics in veterinary medicine and their negligent use among dog owners have contributed to the rise of antibiotic resistance in microorganisms found in pets. In addition, the search for medicinal plants with antibacterial properties has made the evaluation of aqueous extracts of Alpinia purpurata (Vieill.) K. Schum an important issue. Thus, the aim of this work was to determine the antibiotic resistance profile of gram-negative bacteria isolated from nasal swab samples of dogs and assess the antibacterial activity of the aqueous extracts of leaves and rhizomes of A. purpurata. The bacteria identified were tested using the agar disc diffusion assay for the evaluation of antibiotic resistance. A total of 16 isolates were obtained from the 19 samples collected, with a high prevalence of Escherichia coli (n=5). There was a high rate of resistance to ?-lactams, where the highest percentage was seen for amoxicillin (72.5%). Aqueous leaf extracts had high levels of total phenolic compounds (637.47 µg GAE mg-1), differing significantly (p &lt; 0.05) from aqueous rhizome extracts (228.64 µg GAE mg-1). There was no significant difference in EC50 of DPPH values between the aqueous extracts; however, the antioxidant capacity of rhizome extracts had higher values than leaf extracts. The minimum inhibitory concentration (MIC) of leaves and rhizomes for the evaluated bacteria ranged from 9000 to 32,000 µg mL-1. For the minimum bactericidal concentration (MBC), most bacteria showed an MBC over 38,400 µg mL-1 for the rhizome. In conclusion, the bacteria isolated from dog nasal swabs showed a high resistance profile for the antibiotics of the penicillin class. Additionally, the results from the analysis of the aqueous extracts of rhizomes and leaves of A. purpurata showed an antimicrobial effect possibly associated with a high content of total phenolic compounds; these results can create a scope for using these extracts together with conventional antibiotics to control the emergence of antibiotic resistance among microbial species.

Study on antioxidant activity of crude peanut oils and refined cottonseed oils from Burkina Faso

&lt;abstract&gt; &lt;p&gt;Vegetable oils are among the foodstuffs produced and consumed in abundance by the population in Burkina Faso. These edible oils are nutrient sources for health. However, the oxidation of edible oils is a phenomenon that leads to their degradation. Hence, the objectives of this study were to determine the antioxidants compounds, to evaluate the antioxidant activity of vegetable oils produced in Burkina Faso and to propose good manufacturing practices. Thus, 32 samples of crude peanut oils and refined cottonseed oils were analyzed. α-Tocopherol was determined by High performance liquid chromatography (HPLC), total phenolic compounds and DPPH by spectrophotometry. The α-tocopherol averages are 10.89 and 56.44 mg/100 g for peanut oils and cottonseed oils, respectively (&lt;italic&gt;p&lt;/italic&gt; &amp;lt; 0.05). For total phenolic compounds, the averages are 2.91 and 0.64 mg/100 g of gallic acid equivalent for peanut oils and cottonseed oils, respectively (&lt;italic&gt;p&lt;/italic&gt; &amp;lt; 0.05). The inhibition percentages are respectively 17.97% and 5.58% (&lt;italic&gt;p&lt;/italic&gt; &amp;lt; 0.05) for peanut oils and cottonseed oils. For antioxidant activity, the averages are 0.81 and 0.27 mg trolox/100 g for peanut oils and cottonseed oils, respectively (&lt;italic&gt;p&lt;/italic&gt; &amp;lt; 0.05). Cottonseed oils have the highest levels of α-tocopherol while peanut oils have high levels of total phenolic compounds and antioxidant activity. Vegetable oils contain acceptable levels of α-tocopherol and total phenolic compounds for their oxidative stability and health benefits for the consumer. However, the levels of biomolecules will be higher if production and preservation conditions are improved and controlled. The results could be used for future recommendations about human feeding programs in Burkina Faso.&lt;/p&gt; &lt;/abstract&gt;

Chemical composition and evaluation of antioxidant, antimicrobial and antiproliferative activities of Tuber and Terfezia truffles

Ten truffle species of Tuber and Terfezia genera were chemical characterized, assessing their proximate composition, individual nutrient compounds and some bioactive molecules. The bioactive properties of these species were also evaluated, namely their antioxidant, antimicrobial and cytotoxic potential. Carbohydrates were the main macronutrients present in truffles, followed by proteins. Furthermore, the levels of polyunsaturated fatty acids (PUFA), subsequently presented as a percentage, were higher in truffles (38.2–79.3%) except in Tuber magnatum and Terfezia arenaria, which have a more saturated fatty acids (SFA) profile (70.7% and 53.7%, respectively). Comparing the species, T. magnatum revealed the highest levels of total phenolic compounds (TPC) (290 mg GAE/100 g truffle), as also the best results in the four methods used to evaluate the antioxidant activity. On the other hand, only five extracts obtained from some studied truffle species (Terfezia magnusii, Tuber aestivum, Tuber gennadii, and Tuber melanosporum) showed a slight inhibition of microbial growth, tested against different bacteria. Terfezia and T. gennadii extracts, showed potential to inhibit the cellular growth of NCI-H460, HeLa, HepG2, and MCF-7 cell lines (GI50 concentrations range: 19–78, 33–301, 83–321 and 102–321 µg/mL, respectively), indicating anti-proliferative activity. Nevertheless, T. arenaria revealed some potential hepatotoxicity, inhibiting the growth of PLP2 cells (GI50 concentration of 220 µg/mL), a primary cell culture obtained from porcine liver.

Production and antimicrobial activity of trans-resveratrol, trans-arachidin-1 and trans-arachidin-3 from elicited peanut hairy root cultures in shake flasks compared with bioreactors

Obtaining large-scale hairy root cultures is a major challenge to increasing root biomass and secondary metabolite production. Enhanced production of stilbene compounds such as trans-resveratrol, trans-arachidin-1 and trans-arachidin-3 was achieved using an elicitor treatment procedure. Two different hairy root inoculum densities were investigated and compared between shake flask and bioreactor cultures. The lowest growth index was observed using a 20 g/L inoculum size in the bioreactor, which differed significantly from bioreactor of 5 g/L. Increasing the hairy root inoculum size from 5 g/L to 20 g/L in both the shake flask and bioreactor significantly improve antioxidant activity, phenolic content and stilbene compound levels. The highest ABTS and FRAP antioxidant activity, and levels of total phenolic compounds, trans-arachidin-1 and trans-arachidin-3 in the crude extract were demonstrated in shake flask cultures with a 20 g/L inoculum after elicitation for 72 h. The minimum inhibitory concentrations (MICs) of the crude extract to inhibit growth of foodborne microbes, S. aureus, S. typhimurium and E. coli, were 187.5, 250 and 500 μg/mL, respectively. This was due to the ability of the crude extract to disrupt the cell membrane, as observed by scanning electron microscopy (SEM) showing ruptured pores on the S. aureus and S. typhimurium cell surfaces. Moreover, the E. coli cell division process could be inhibited by the crude extract, which promoted an increase in cell size. A DNA nicking assay indicated that a 50 μg/mL concentration of the crude extract caused plasmid DNA damage that might be due to a genotoxic effect of the pro-oxidant activity of the crude extract.

Effect of Roasting and Vacuum Microwave Treatments on Physicochemical and Antioxidant Properties of Oil Extracted from Black Sesame Seeds

Unroasted, roasted (at roasting temperatures of 100, 150 and 200 C and roasting times of 10, 20 and 30 min) and vacuum microwaved (at microwave watt powers of 800, 1440, 2400 and 3600 watts/kg black sesame seeds, for heating times of 10, 20 and 30 min) black sesame seeds were processed to extract oil using a single screw press at a constant pressing temperature of 50 C. The results revealed that different heat pre-treatments significantly affected yield and physiochemical and antioxidant properties of extracted oils. The extracted oil samples exhibited significantly different levels of total phenolic compounds, sesamin, sesamolin, and DPPH• and ABTS•+ scavenging activity. Additionally, it was found that these values of roasted and vacuum microwaved black sesame seed oils were significantly higher than those of unroasted oil. Sesamin, sesamolin, total content of phenolic compounds, and DPPH• and ABTS•+ scavenging activity of extracted black sesame oils increased when the roasting temperature and watt power increased. Black sesame oil obtained from unroasted, roasted and vacuum microwaved dried black sesame seeds contained linoleic and oleic acids as major fatty acids. Black sesame oil extracted from roasting and vacuum microwave treatments for 10 min at higher roasting temperature and microwave watt power had higher total phenolic content leading to a reduction of peroxide value and elevated stability of soybean oil when it was added during storage time at temperature of 65 °C.

Eliciting effect of foliar application of chitosan lactate on the phytochemical properties of Ocimum basilicum L. and Melissa officinalis L.

An increase in the content of secondary metabolites in herbal plants is desirable due to their therapeutic and nutraceutical properties. Therefore, the effects of foliar spray of 100 mg/L or 500 mg/L of chitosan lactate (ChL) on the accumulation of selected phenolics and physiological parameters of basil and lemon balm were investigated. In basil, the concentration of rosmarinic acid (RA) increased after application of 100 mg/L of ChL. In turn, in lemon balm both ChL concentrations increased the accumulation of RA and anthocyanins, while the level of total phenolic compounds (TPC) was elevated only at the dose of 100 mg/L of ChL. Elicitation of basil with 500 mg/L of ChL increased the shoot biomass. Therefore, such an elicitor as ChL can enhance the accumulation of valuable phytochemicals in Lamiaceae species. This simple and non-laborious method can be used for elicitation of herbal plants in production of functional food.