Correlations between phenolic content and antioxidant properties in twenty-four plant species of traditional ethnoveterinary use in the Mediterranean area

The Health-Benefits and Phytochemical Profile of Salvia apiana and Salvia farinacea var. Victoria Blue Decoctions

Salvia apiana and Salvia farinacea var. Victoria Blue decoctions were screened for diverse bioactivities, including the ability to counteract oxidative and inflammatory events, as well as to act as cytotoxic and antimicrobial agents. Both extracts showed good activities and that of S. apiana origin was particularly effective regarding the ability to prevent lipid peroxidation and to prevent nitric oxide (NO●) production in lipopolysaccharide (LPS)-activated murine macrophage RAW 264.7 cell line (EC₅₀ = 50 μg/mL). Moreover, it displayed high cytotoxic capacity against hepatocellular carcinoma HepG2, cervical carcinoma HeLa, and breast carcinoma cells MCF-7, but comparatively low effects in porcine liver primary cells, which highlights its selectivity (GI₅₀ = 41–60 μg/mL vs. 362 μg/mL, respectively). Further, it exhibited inhibitory and lethal potential against a panel of Gram-positive and Gram-negative bacteria. It is possible that the bioactive properties of the two Salvia extracts are associated to their phenolic components and, in the particular case of S. apiana, to its richness in phenolic terpenes, namely in rosmanol, hydroxycarnosic acid and a derivative of sageone, which were found in the extract.

Antioxidant Sources from Leaves of Russian Dandelion

Taraxacum kok-saghyz (TKS) is a dandelion species native to Kazakhstan, Uzbekistan and north-west China, considered as a promising alternative source of natural rubber from its roots. The aim of this study was to investigate the possible exploitation of TKS leaves, a rubber byproduct, as a source of phenolic compounds with antioxidant properties for potential applications in forage, nutraceutical and pharmacological fields. Two accessions (TKS016, TKS018) grown under Mediterranean conditions of Sardinia were evaluated at vegetative and flowering stages. The leaves of TKS018 had the highest antioxidant capacity (19.6 mmol trolox equivalent antioxidant capacity 100 g^-1 ), total phenolic (106.4 g gallic acid equivalent kg^-1 ), tannic phenolics (58.5 g gallic acid equivalent kg^-1 ) and total flavonoid contents (22.9 g catechin equivalent kg^-1 ). At both phenological stages, TKS016 showed significantly lower values than TKS018 in 1,1-diphenyl-2-picrylhydrazyl (DPPH), total phenolic and tannic phenolics. Six individual molecules were identified, namely chlorogenic, cryptochlorogenic, caffeic, sinapic, chicoric and 3,4-dimethoxycinnamic acids. Chicoric (8.53-10.68 g kg^-1 DW) and chlorogenic acids (4.18-7.04 g kg^-1 DW) were the most abundant. TKS leaves represent a valuable source of chicoric acid with potential application as antioxidant to be used as herbal medicine and nutrition for production of healthy food/feed.

Comparison of olive leaf, olive oil, palm oil, and omega-3 oil in acute kidney injury induced by sepsis in rats

Background

Hypotension, increased production of reactive oxygen species, and inflammation are all observed in experimental models of sepsis induced by lipopolysaccharide (LPS).

Purpose

The aim of this study was to evaluate the effects of an ethanolic extract of Brazilian olive leaf (Ex), Brazilian olive oil (Olv), Ex + Olv (ExOlv), and palm oil (Pal) in comparison to the effects of omega-3 fish oil (Omg) in a rat model of sepsis-induced acute kidney injury.

Materials

Wistar rats were divided into seven groups (seven per group), which were either untreated (control) or treated with LPS, LPS + Ex, LPS + ExOlv, LPS + Olv, LPS + Omg, or LPS + Pal.

Results

Lower values of creatinine clearance and blood pressure were observed in the LPS-treated group, and these values were not affected by Ex, Olv, ExOlv, Pal, or Omg treatment. Mortality rates were significantly lower in rats exposed to LPS when they were also treated with Ex, ExOlv, Olv, Pal, or Omg. These treatments also decreased oxidative stress and inflammation (Tumor necrosis factor alpha, interleukin-1 beta) and increased interleukin-10 levels and cell proliferation, which were associated with decreased apoptosis in kidney tissue.

Conclusion

Ex and Pal treatments were beneficial in septic rats, since they increased survival rate and did not aggravate inflammation. However, the most effective treatments for septic rats were Olv in comparison to Omg. These natural food substances could enable the development of effective therapeutic interventions to sepsis.

Allium porrum Extract Decreases Effector Cell Degranulation and Modulates Airway Epithelial Cell Function

Allium genus plants, such as leek (Allium porrum), are rich sources of anti-inflammatory and anti-oxidant secondary metabolites; this is of interest because it demonstrates their suitability as pharmacological alternatives for inflammatory processes, including allergy treatment. The composition of methanolic leek extract (LE) was analyzed by GC-MS and LC-IT/MS, and the total phenolic content and antioxidant capacity were quantified by colorimetric methods. Its pharmacological potential was analyzed in human bronchial epithelial Calu-3 cells, human mast cells LAD2, and humanized rat basophiles RBL-2H3. LE exhibited a cytotoxic effect on Calu-3 cells and HumRBL-2H3 cells only at high concentrations and in a dose-dependent manner. Moreover, LE decreased the degranulation of LAD2 and HumRBL-2H3 cells. LE treatment also significantly prevented alterations in transepithelial electrical resistance values and mRNA levels of glutathione-S-transferase (GST), c-Jun, and NFκB after treatment with H2O2 in ALI-cultured Calu-3 cells. Finally, ALI-cultured Calu-3 cells treated with LE showed lower permeability to Ole e 1 compared to untreated cells. A reduction in IL-6 secretion in ALI-cultured Calu-3 cells treated with LE was also observed. In summary, the results obtained in this work suggest that A. porrum extract may have potential anti-allergic effects due to its antioxidant and anti-inflammatory properties. This study provides several important insights into how LE can protect against allergy.

Efficiency of Tinospora crispa against Culex quinquefasciatus larva

Tinospora crispa stem aqueous extractions for various time durations were determined regarding their total phenolic content and their larvicidal abilities. The results revealed that the total phenolic content in 1-, 3-, 5-, 10-, and 24-h extracts were 8.26, 8.43, 13.57, 12.52, and 12.43 mg/g gallic acid equivalent, respectively. The 5-h extract of T. crispa was evaluated against Culex quinquefasciatus mosquito larva in concentrations 3.125, 6.25, 12.5, and 25 mg/l, by determining the lethal concentration (LC) within 24 h and by histopathological analysis. The 24-h LC₅₀ and LC₉₀ values were 16.95 and 30.12 mg/l, respectively. The histopathological lesions after exposure to 50% of the 24-h LC₅₀ were observed primarily in the midgut of the larva. The lesions observed were for the example epithelial cells lifting from the basement membrane, cell elongation protruding into the lumen, brush border disrupting with absent microvilli, and vesicle appearance. The present study indicated that the aqueous extract of this herb may have a suitable property for a larvicidal natural product and may replace harmful chemical pesticides.

Blood pressure lowering effect of Ficus deltoidea var kunstleri in spontaneously hypertensive rats: possible involvement of renin-angiotensin-aldosterone system, endothelial function and anti-oxidant system

This study investigated the effects of a standardised ethanol and water extract of Ficus deltoidea var. Kunstleri (FDK) on blood pressure, renin-angiotensin-aldosterone system (RAAS), endothelial function and antioxidant system in spontaneously hypertensive rats (SHR). Seven groups of male SHR were administered orally in volumes of 0.5 mL of either FDK at doses of 500, 800, 1000 and 1300 mg kg^- 1, or captopril at 50 mg kg^- 1 or losartan at 10 mg kg^- 1 body weight once daily for 4 weeks or 0.5 mL distilled water. Body weight, systolic blood pressures (SBP) and heart rate (HR) were measured every week. 24-hour urine samples were collected at weeks 0 and 4 for electrolyte analysis. At week 4, sera from rats in the control and 1000 mg kg^- 1 of FDK treated groups were analyzed for electrolytes and components of RAAS, endothelial function and anti-oxidant capacity. SBP at week 4 was significantly lower in all treatment groups, including captopril and losartan, when compared to that of the controls. Compared to the controls, ACE activity and concentrations of angiotensin I, angiotensin II and aldosterone were lower whereas concentrations of angiotensinogen and angiotensin converting enzyme 2 were higher in FDK treated rats. Concentration of eNOS and total anti-oxidant capacity were higher in FDK treated rats. Urine calcium excretion was higher in FDK treated rats. In conclusion, it appears that ethanol and water extract of FDK decreases blood pressure in SHR, which might involve mechanisms that include RAAS, anti-oxidant and endothelial system.

Resin foraging dynamics in Varroa destructor-infested hives: a case of medication of kin?

Social insects have evolved colony behavioral, physiological, and organizational adaptations (social immunity) to reduce the risks of parasitization and/or disease transmission. The collection of resin from various plants and its use in the hive as propolis is a clear example of behavioral defense. For Apis mellifera, an increased propolis content in the hive may correspond to variations in the microbial load of the colony and to a downregulation of an individual bee's immune response. However, many aspects of such antimicrobial mechanism still need to be clarified. Assuming that bacterial and fungal infection mechanisms differ from the action of a parasite, we studied the resin collection dynamics in Varroa destructor-infested honeybee colonies. Comparative experiments involving hives with different mite infestation levels were conducted in order to assess the amount of resin collected and propolis quality within the hive, over a 2-year period (2014 and 2015). Our study demonstrates that when A. mellifera colonies are under stress because of Varroa infestation, an increase in the number of resin foragers is recorded, even if a general intensification of the foraging activity is not observed. A reduction in the total polyphenolic content in propolis produced in infested versus uninfested hives was also noticed. Considering that different propolis types show varying levels of inhibition against a variety of honey bee pathogens in vitro, it would be very important to study the effects against Varroa of two diverse types of propolis: from Varroa-free and from Varroa-infested hives.

Phytochemical screening, antioxidant activity and inhibitory potential of Ficus carica and Olea europaea leaves

It is our interest to screen Oela europaea L and Ficus carica L leaf extract for total phenolic, flavonoid contents and to evaluate their free radical scavenging and Ferric reducing power (FRAP) using 1,1-diphenyl-2-picrylhydrazyl (DPPH). Data shows that Olea europaea and Ficus carica have strong antioxidant potency to scavenge free radical at an optimal phenolic and flavonoid concentration. Results further suggest a strong correlation between antioxidant activities, phenolic and flavonoid contents. Thus, the screening of Ficus carica and Olea europaea leaf extracts for potential antioxidants as source of drugs for several diseases especially oxidative stress and cancers is illustrated.

Polyphenolic composition and antioxidant capacity of legume-based swards are affected by light intensity in a Mediterranean agroforestry system

BACKGROUND

In Mediterranean grazed woodlands, microclimate changes induced by trees influence the growth and development of the understory, although very little is known about its polyphenolic composition in relation to light intensity. We investigated the bioactive compounds and antioxidant capacity of different legume-based swards and variations as a result of full sunlight and partial shade. The research was carried out in a cork oak agrosilvopastoral system in Sardinia.

RESULTS

The highest values of (1,1-diphenyl-2-picrylhydrazyl) (DPPH) reached 7 mmol Trolox equivalent antioxidant capacity 100 g^-1 dry weight (DW), total phenolics 67.1 g gallic acid equivalent kg^-1 DW and total flavonoids 7.5 g catechin equivalent kg^-1 DW. Compared to full sunlight, partial shade reduced DPPH values by 29% and 42%, and the total phenolic content by 23% and 53% in 100% legume mixture and semi-natural pasture, respectively. Twelve phenolic compounds were detected: chlorogenic acid in 80% legume mixture (partial shade) and verbascoside in pure sward of bladder clover (full sunlight) were the most abundant.

CONCLUSION

Light intensity significantly affected antioxidant capacity, composition and levels of phenolic compounds. The results of the present study provide new insights into the effects of light intensity on plant secondary metabolites from legume-based swards, highlighting the important functions provided by agroforestry systems. © 2018 Society of Chemical Industry.

Far Infrared Irradiation Enhances Nutraceutical Compounds and Antioxidant Properties in Angelica gigas Nakai Powder

The aim of this study was to investigate the effect of far infrared irradiation (FIR) on nutraceutical compounds, viz. total phenolic content, total flavonoids, and antioxidant capacity, of Angelica gigas Nakai (AGN). The FIR treatment was applied for 30 min with varied temperatures of 120, 140, 160, 180, 200, 220, and 240 °C. Results showed that FIR increased total phenolic and flavonoid content in AGN at 220 °C. The HPLC results revealed higher quantities of decursin (62.48 mg/g) and decursinol angelate (41.51 mg/g) at 220 °C compared to control (38.70 mg/g, 27.54 mg/g, respectively). The antioxidant capacity of AGN was also increased at 220 °C, as measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and the phosphomolybdenum (PPMD) method. A further increase of the FIR temperature caused a reduction of compound content. In addition, the results also showed a strong correlation between phenolic content and antioxidant properties of AGN powder. These findings will help to further improve the nutraceutical profile of AGN powder by optimizing the FIR conditions.

Enhancement of Bioactivity of Natural Extracts by Non-Thermal High Hydrostatic Pressure Extraction

Natural extracts, like those obtained from medicinal herbs, dietary plants and fruits are being recognized as important sources of bioactive compounds with several functionalities including antioxidant, anticancer, and antimicrobial activities. Plant extracts rich in phenolic antioxidants are currently being successfully used for several pharmaceutical applications and in the development of new foods (i.e., functional foods), in order to enhance the bioactivity of the products and to replace synthetic antioxidants. The extraction method applied in the recovery of the bioactive compounds from natural materials is a key factor to enhance the bioactivity of the extracts. However, most of the extraction techniques have to employ heat, which can easily lead to heat-sensitive compounds losing their biological activity, due to changes caused by temperature. Presently, high hydrostatic pressure (HHP) is being increasingly explored as a cold extraction method of bioactive compounds from natural sources. This non-thermal high hydrostatic pressure extraction (HHPE) technique allows one to reduce the extraction time and increase the extraction of natural beneficial ingredients, in terms of nutritional value and biological activities and thus enhance the bioactivity of the extracts. This review provides an updated and comprehensive overview on the extraction efficiency of HHPE for the production of natural extracts with enhanced bioactivity, based on the extraction yield, total content and individual composition of bioactive compounds, extraction selectivity, and biological activities of the different plant extracts, so far studied by extraction with this technique.

Effects of Thermal Processing on the Nutritional, Antinutrient, and In Vitro Antioxidant Profile of Monodora myristica (Gaertn.) Dunal Seeds

Proximate, minerals, and anti-nutrient content of raw Monodora myristica seed and Monodora myristica seeds boiled and roasted for 10, 20, and 30 min, respectively were assessed. In addition, the effects of boiling and roasting for 10, 20, and 30 min on the antioxidant properties of Monodora myristica seed extract were evaluated. Results showed that moisture, ash, fat, and crude protein were significantly reduced by boiling and roasting. Acid and neutral detergent fibres were significantly increased by roasting and boiling, with boiling causing a more significant increase than roasting. Processing resulted in significant decrease in magnesium, potassium, phosphorus, zinc, copper, manganese, and iron while calcium levels were unchanged. Total phenolics levels of raw seeds [(21.94 mg/100 g gallic acid equivalent (GAE)] showed a remarkable decrease (18.64 mg/100 g GAE) when the boiling time was increased to 30 min. Free fraction phenolics increased with thermal processing whereas bound phenolics decreased. Boiling was more effective in reducing anti-nutrients than roasting. Extracts of Monodora myristica seeds possess significant 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azinobis( 3-ethylbenzothiazoline-6-sulphonic acid) free radical scavenging properties in a concentration-dependent manner, and this was significantly reduced after thermal processing. Monodora myristica seed extracts could be pharmaceutically exploited for antioxidant properties, and roasting may be preferred to retain the nutrient composition and antioxidant properties of Monodora myristica seeds.

Comparative Study of the in vitro Antioxidant Properties of Methanolic Extracts of Chromolaena odorata and Ageratum conyzoides used in Wound Healing

This study sought to evaluate the potential antioxidative potencies of Chromolaena odorata and Ageratum conyzoides,  commonly used herbs in Nigeria for wound first aid and healing. The antioxidant potentials were evaluated by measuring their abilities to scavenge radicals, reduce oxidised iron and quench the formation of lipid peroxides. The findings showed that the extract of Ageratum conyzoides exhibited significantly higher (p<0.05) antioxidant potential than the extract of Chromolaena odorata. The study, therefore, suggests that Ageratum conyzoides has higher potential for therapeutic value than Chromolaena odorata in terms of antioxidant potential.

Antidiabetic activity, glucose uptake stimulation and α-glucosidase inhibitory effect of Chrysophyllum cainito L. stem bark extract

Background

Chrysophyllum cainito L., a tropical fruit tree, has been used as an alternative medicine for the treatment of diabetic patients in many countries. However, there is very limited scientific rationale for this medical use. The present study aimed to evaluate the antidiabetic activity of the extract from C. cainito stem bark and the possible mechanisms underlying this activity.

Methods

Phytochemistry and in vitro antioxidant capacity of the extract were studied. Hypoglycemic activity of the extract was examined in normal and alloxan-induced diabetic mice. The effect of C. cainito extract on glucose absorption and glucose uptake were conducted using mouse isolated jejunum and abdominal muscle, respectively. Finally, an in vitro effect of C. cainito extract on α-glucosidase activity was evaluated.

Results

C. cainito extract possessed a strong antioxidant activity comparable to the ascorbic acid and butylated hydroxytoluene. The extract at 500 mg/kg significantly reduced the area under curve of blood glucose level in oral glucose tolerance test in normal mice. In alloxan-induced diabetic model, similar to glibenclamide, a single dose of the extract significantly decreased fasting blood glucose level from 387.17 ± 29.84 mg/dl to 125.67 ± 62.09 mg/dl after 6 h of administration. From the isolated jejunum experiment, the extract at any doses used did not inhibit glucose absorption. However, the extract at 50 μg/ml significantly increased the amount of glucose uptake by abdominal muscles in the presence of insulin (P < 0.05). Lastly, it was found that the extract produced stronger inhibition of α-glucosidase activity (IC₅₀ = 1.20 ± 0.09 μg/ml) than acarbose (IC₅₀ = 198.17 ± 4.74 μg/ml).

Conclusion

Direct evidence of antidiabetic activity of C. cainito stem bark with possible modes of action, glucose uptake stimulation and α-glucosidase inhibitory effect, was reported for the first time herein. These data support the potential use of this plant for the treatment of diabetic patients.

In vitro and in vivo studies of Allium sativum extract against deltamethrin-induced oxidative stress in rats brain and kidney

The present study investigated the in vitro and the in vivo antioxidant capacities of Allium sativum (garlic) extract against deltamethrin-induced oxidative damage in rat's brain and kidney. The in vitro result showed that highest extraction yield was achieved with methanol (20.08%). Among the tested extracts, the methanol extract exhibited the highest total phenolic, flavonoids contents and antioxidant activity. The in vivo results showed that deltamethrin treatment caused an increase of the acetylcholinesterase level (AChE) in brain and plasma, the brain and kidney conjugated dienes and lipid peroxidation (LPO) levels as compared to control group. The antioxidant enzymes results showed that deltamethrin treatment induced a significantly decrease (p < 0.01) in brain and kidney antioxidant enzymes as catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) to control group. The co-administration of garlic extract reduced the toxic effects in brain and kidney tissues induced by deltamethrin.

Effect of Pinocembrin Isolated from Mexican Brown Propolis on Diabetic Nephropathy

Propolis is a resinous beehive product that has been used worldwide in traditional medicine to prevent and treat colds, wounds, rheumatism, heart disease and diabetes. Diabetic nephropathy is the final stage of renal complications caused by diabetes and for its treatment there are few alternatives. The present study aimed to determine the chemical composition of three propolis samples collected in Chihuahua, Durango and Zacatecas and to evaluate the effect of pinocembrin in a model of diabetic nephropathy in vivo. Previous research demonstrated that propolis of Chihuahua possesses hypoglycemic and antioxidant activities. Two different schemes were assessed, preventive (before renal damage) and corrective (once renal damage is established). In the preventive scheme, pinocembrin treatment avoids death of the rats, improves lipid profile, glomerular filtration rate, urinary protein, avoid increases in urinary biomarkers, oxidative stress and glomerular basement membrane thickness. Whereas, in the corrective scheme, pinocembrin only improves lipid profile without showing improvement in any other parameters, even pinocembrin exacerbated the damage. In conclusion, pinocembrin ameliorates diabetic nephropathy when there is no kidney damage but when it is already present, pinocembrin accelerates kidney damage.

Characterization of Essential Oils Obtained from Abruzzo Autochthonous Plants: Antioxidant and Antimicrobial Activities Assessment for Food Application

In the present study, the essential oils (EOs) of some officinal plants from Abruzzo territory (Italy) were evaluated for their antimicrobial and antioxidant activities and their volatile fraction chemical characterization. The EOs were extracted from Rosmarinus officinalis, Origanum vulgare, Salvia officinalis, Mentha piperita, Allium sativum, Foeniculum vulgare, Satureja montana, Thymus vulgaris and Coriandrum sativum seeds. The antimicrobial activity was screened against thirteen Gram-positive and Gram-negative strains to determine the Minimal Inhibitory Concentration (MIC). The total phenolic content (TPC) and the antioxidant capacity (AOC) were assessed by means of Folin-Ciocâlteu method, and Trolox Equivalent Antioxidant Capacity with 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid (TEAC/ABTS), Ferric Reducing Antioxidant Power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays respectively. Among the nine EOs tested, T. vulgaris, S. montana, O. vulgare and C. sativum EOs showed MIC values ranging from 0.625 to 5 μL/mL. The AOC and TPC results for these species were also interesting. The major components for these EOs were thymol for T. vulgaris (44%) and O. vulgare (40%), linalool (77%) for C. sativum, and carvacrol for S. montana (54%). The results allowed the study to establish that these EOs are good candidates for potential application as biopreservatives in foods and/or food manufacture environments.

The Influence of the Osmotic Dehydration Process on Physicochemical Properties of Osmotic Solution

The osmotic dehydration (OD) process consists of the removal of water from a material during which the solids from the osmotic solution are transported to the material by osmosis. This process is commonly performed in sucrose and salt solutions. Taking into account that a relatively high consumption of those substances might have a negative effect on human health, attempts have been made to search for alternatives that can be used for osmotic dehydration. One of these is an application of chokeberry juice with proven beneficial properties to human health. This study aimed to evaluate the physicochemical properties of the OD solution (chokeberry juice concentrate) before and after the osmotic dehydration of carrot and zucchini. The total polyphenolics content, antioxidant capacity (ABTS, FRAP), dynamic viscosity, density, and water activity were examined in relation to the juice concentration used for the osmotic solution before and after the OD process. During the osmotic dehydration process, the concentration of the chokeberry juice decreased. Compounds with lower molecular weight and lower antioxidant capacity present in concentrated chokeberry juice had a stronger influence on the exchange of compounds during the OD process in carrot and zucchini. The water activity of the osmotic solution increased after the osmotic dehydration process. It was concluded that the osmotic solution after the OD process might be successfully re-used as a product with high quality for i.e. juice production.

Development of a Rapid and Simple Method to Remove Polyphenols from Plant Extracts

Polyphenols are secondary metabolites of plants, which are responsible for prevention of many diseases. Polyvinylpolypyrrolidone (PVPP) has a high affinity towards polyphenols. This method involves the use of PVPP column to remove polyphenols under centrifugal force. Standards of gallic acid, epigallocatechin gallate, vanillin, and tea extracts (Camellia sinensis) were used in this study. PVPP powder was packed in a syringe with different quantities. The test samples were layered over the PVPP column and subjected to centrifugation. Supernatant was tested for the total phenol content. The presence of phenolic compounds and caffeine was screened by HPLC and measuring the absorbance at 280. The antioxidant capacity of standards and tea extracts was compared with the polyphenol removed fractions using DPPH scavenging assay. No polyphenols were found in polyphenolic standards or tea extracts after PVPP treatment. The method described in the present study to remove polyphenols is simple, inexpensive, rapid, and efficient and can be employed to investigate the contribution of polyphenols present in natural products to their biological activity.

Comparison of Drying and Quality Characteristics of Pear (Pyrus Communis L.) Using Mid-Infrared-Freeze Drying and Single Stage of Freeze Drying

This article provides results of an experimental investigation of hybrid- (MIR-FD), mid-infrared- (MIR) and freeze drying (FD) on the drying characteristics, energy consumption and quality parameters of pear. Rehydration ratio, color, texture, water activity, phenolic content and antioxidant activity were measured to evaluate the quality of dried pear products. Mid-infrared-freeze drying (MIR-FD) had the higher drying rate, which reduced the drying time by 14.3–42.9 % compared with FD method. Two empirical models were chosen to fit the drying curves and the models had the suitable R2 and RMSE values. Temperature characteristics of MIR and MIR-FD dried pear were determined in terms of interior temperature variation. The MIR-FD pear had darker color, better rehydration capacity, similar water activity, lower hardness (except of MIR-FD70°C) and highest content of chemical composition than single stage of FD products. Above all, the MIR50-60°C-FD was suggested as the best drying method for pear in this study.

Secondary metabolites and metal content dynamics in Teucrium montanum L. and Teucrium chamaedrys L. from habitats with serpentine and calcareous substrate

The purpose of this comparative analysis is the determination of the total quantity of metals (Mg, Ca, K, Ni, Fe, Mn, Zn, Cu, Cr and Pb) in soil samples, above ground plant parts and tea made of plants Teucrium montanum and T. chamaedrys from different serpentine and calcareous habitats as well as of the total quantity of phenolic compounds and antioxidant activity. The obtained results showed that the quantities of certain metals (Mg, Fe, Ni and Mn) in the soil from the serpentine habitats were greater in comparison with other metals (Ca, Zn and Pb) which were more frequently found in the soil from the calcareous habitats. The results demonstrated that the analysed plant samples from the serpentine habitats contained higher quantity of Fe, Ni and Cr as opposed to the plant samples from the calcareous habitats which contained greater quantity of Ca and Zn. Although the studied species accumulate analysed metals in different quantities, depending on the substrate type, they are not hyperaccumulators of these metals. The use of these species from serpentine habitats for tea preparation is safe to a great extent, because in spite of the determined metal absorption by plant organs, the tea does not contain dangerous quantity of heavy metals. The results showed greater total quantity of phenolic compounds and the higher level of antioxidant activity in the plant samples from serpentine habitats in comparison with the samples from calcareous habitats, which is an indicator of one of the mechanisms of adaptation to the serpentine habitat conditions.

Spectrophotometric determination of the total phenolic content, spectral and fluorescence study of the herbal Unani drug Gul-e-Zoofa (Nepeta bracteata Benth)

Objectives

This study quantitatively determined the total phenolic contents in ethanolic and aqueous extracts of Gul-e-Zoofa (flowers of Nepeta bracteata Benth) using a spectrophotometric method. We also performed a spectral study (UV and IR) of the ethanolic extract and a fluorescence study of the powdered drug and successive extracts to identify and characterize the genuine herbal drug, which has not been previously performed.

Methods

The total phenolic content was determined quantitatively using the Folin Ciocalteu reagent, with Gallic acid as the standard. The fluorescence characteristics of the powdered drug and successive extracts with and without chemical treatment during the day and under a UV light were recorded. The UV and IR spectra of the alcoholic extract of Gul-e-Zoofa were recorded using a spectrometer.

Results

The total phenolic contents of the alcoholic and aqueous extracts were found to be 326.28 and 319.14 mg/g of the Gallic acid equivalent (GAE), respectively. The wavelength of the maximum absorption in the UV spectrum was 320 nm, and the characteristic frequencies in the IR spectrum were 3465.31, 3220.07, 2927.3, 2856.1, 1709.07, 1610.19, 1404.5, 1250.2, 1056.42, 823.04, 775.58, 577.81, and 463.10 cm⁻¹. The fluorescence characteristics of the powdered drug were also observed.

Conclusion

This spectral and fluorescence study of the drug will be helpful for confirming the identity and purity of the genuine drug. The total phenolic content will be helpful for developing new drugs and standardizing the drug. The presence of a high total phenolic content shows that the flowers of N. bracteata Benth may possess antioxidant properties, which could lead to a new field of research in the future.

Antioxidant activity, phenolic-flavonoid content and high-performance liquid chromatography profiling of three different variants of Syzygium cumini seeds: A comparative study

BACKGROUND

The medicinally important phytochemicals present in Syzygium cumini seeds probably accounts for its wide use in traditional systems of medicines in India, like Ayurveda, Unani, and Siddha.

AIM

The aim of the study was to determine the antioxidant potential of three different geographical variants of S. cumini seeds and to compare the phenolic profiling to know the effect of geographical variation in phenolic composition.

MATERIALS AND METHODS

Total phenolic and flavonoid content of S. cumini seeds were analyzed. Antioxidant activities in terms of 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), nitric oxide and superoxide radical scavenging assays were performed. The most active fractions were subjected to high-performance liquid chromatography (HPLC) profiling to identify the phenolic composition.

RESULTS

Among all the fractions, 70% methanol fraction of S. cumini seed showed significant antioxidant potential. There existed a linear correlation between phenolic content and antioxidant activity. HPLC profiling of 70% methanol (ME) fractions of all the variants revealed the presence of phenolic compounds with high concentrations of ellagic acid and gallic acid. The differences in phenolic concentration due to geographical changes might be the reason for higher antioxidant potential showed by 70% ME of Trivandrum variant.

CONCLUSION

70% methanolic fraction of S. cumini can act as a novel source of natural antioxidant.

The correlation between antimutagenic activity and total phenolic content of extracts of 31 plant species with high antioxidant activity

Background

Antimutagenic activity of plant extracts is important in the discovery of new, effective cancer preventing agents. There is increasing evidence that cancer and other mutation-related diseases can be prevented by intake of DNA protective agents. The identification of antimutagenic agents present in plants presents an effective strategy to inhibit pathogenic processes resulting from exposure to mutagenic and/or carcinogenic substances present in the environment. There are no reports on the antimutagenic activities of the plant species investigated in this study. Many mutations related to oxidative stress and DNA damage by reactive oxygen species (ROS) and reactive nitrogen species (RNS) have been identified in numerous human syndromes. Oxidative DNA damage plays a significant role in mutagenesis, cancer, aging and other human pathologies. Since oxidative DNA damage plays a role in the pathogenesis of several chronic degenerative diseases, the decrease of the oxidative stress could be the best possible strategy for prevention of these diseases. Antioxidant compounds can play a preventative role against mutation-related diseases, and thus have potential antimutagenic effects.

Methods

The number of antioxidant compounds present in methanol leaf extracts of 120 plant species was determined using a combination of Thin Layer Chromatography (TLC) and spraying with 2, 2-diphenyl-1-picrylhydrazyl (DPPH). The 31 most promising extracts were selected for further assays. The quantitative antioxidant activity was determined using DPPH free radical scavenging spectrophotometric assay. Total phenolic contents were determined using the Folin-Ciocalteu colorimetric assay. The mutagenicity of 31 selected extracts was determined in the Ames test using Salmonella typhimurium strains TA98 and TA100. The antimutagenicity of the plant extracts against 4-nitroquinoline 1-oxide (4-NQO) was also determined using the Ames test.

Results

Of the 120 plant extracts assayed qualitatively, 117 had some antioxidant activity. The selected 31 extracts contained well defined antioxidant compounds. These species had good DPPH free radical antioxidant activity with EC₅₀ values ranging from 1.20 to 19.06 μg/ml. Some of the plant extracts had higher antioxidant activity than L-ascorbic acid (vitamin C). The total phenolic contents ranged from 5.17 to 18.65 mg GAE (gallic acid equivalent)/g plant extract). The total phenolic content of the plant extracts correlated well with the respective antioxidant activity of the plant extracts. No plant extract with good antioxidant activity had mutagenic activity. Several extracts had antimutagenic activity. The percentage inhibition of 4-NQO ranged from 0.8 to 77% in Salmonella typhimurium TA98 and from 0.8 to 99% in strain TA100. There was a direct correlation between the presence of antioxidant activity and antimutagenic activity of the plant extracts. Although no plant extract had mutagenic activity on its own, some of the plant extracts enhanced the mutagenicity of 4-NQO, a phenomenon referred to as comutagenicity.

Conclusions

Some of the plant extracts investigated in this study had potential antimutagenic activities. The antimutagenic activities may be associated with the presence of antioxidant polyphenols in the extracts. From the results plant extracts were identified that were not mutagenic, not cytotoxic and that may be antimutagenic in the Ames test. For most plant extracts, at the highest concentration used (5 mg/ml), the level of antimutagenicity was below the recommended 45% to conclude whether plants have good antimutagenic activity. However, in most screening studies for antimutagenesis, a 20% decrease in the number of revertants must be obtained in order to score the extract as active. Psoralea pinnata L. had the highest percentage antimutagenicity recorded in this study (76.67 and 99.83% in S. typhimurium TA98 and TA100 respectively) at assayed concentration of 5 mg/ml.

The results indicate that investigating antioxidant activity and the number of antioxidant compounds in plant extracts could be a viable option in searching for antimutagenic compounds in plants.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-016-1437-x) contains supplementary material, which is available to authorized users.

Antioxidant Activity/Capacity Measurement. 3. Reactive Oxygen and Nitrogen Species (ROS/RNS) Scavenging Assays, Oxidative Stress Biomarkers, and Chromatographic/Chemometric Assays

There are many studies in which the antioxidant potential of different foods have been analyzed. However, there are still conflicting results and lack of information as a result of unstandardized assay techniques and differences between the principles of the methods applied. The measurement of antioxidant activity, especially in the case of mixtures, multifunctional or complex multiphase systems, cannot be evaluated satisfactorily using a simple antioxidant test due to the many variables influencing the results. In the literature, there are many antioxidant assays that are used to measure the total antioxidant activity/capacity of food materials. In this review, reactive oxygen and nitrogen species (ROS/RNS) scavenging assays are evaluated with respect to their mechanism, advantages, disadvantages, and potential use in food systems. On the other hand, in vivo antioxidant activity (AOA) assays including oxidative stress biomarkers and cellular-based assays are covered within the scope of this review. Finally, chromatographic and chemometric assays are reviewed, focusing on their benefits especially with respect to their time saving, cost-effective, and sensitive nature.

Uses of plants, animal and mineral substances in Mediterranean ethno-veterinary practices for the care of small ruminants

ETHNO-PHARMACOLOGICAL RELEVANCE

The cultural heritage of Sardinian shepherds is rapidly vanishing and survives in the memory of elderly people. The objective of our study was not only to report the usage of plants and their preparation for administration but also the use of other remedies of different origin arising from traditional ethno-veterinary knowledge, as Sardinian shepherds were used to employ plants, animals, minerals and combinations of several substances to prepare remedies for prophylaxis or therapy on their animals.

MATERIALS AND METHODS

The work was carried out in rural areas of the island of Sardinia (Italy) by interviewing shepherds and filling questionnaires in order to record ethno-veterinary practices traditionally used for animal health care.

RESULTS

Ethno-veterinary remedies traditionally utilised for treatments of small ruminants against ecto-and endo-parasites, gastrointestinal diseases, viral and bacterial diseases, wounds, sprains and bruises were identified. Non herbal remedies outnumbered the herbal ones, as usually plant species were mainly used for the care of cattle and equines. A total of 150 ethno-veterinary uses were documented for the treatment of 33 animal conditions, a detailed account of the formulations and their administration to sheep and goats was provided. Herbal remedies involved the use of twenty two spontaneous species and seven cultivated species.

CONCLUSIONS

This study identifies remedies used in ethno-veterinary practices for small ruminants care in Sardinia, the second major Mediterranean island which has agro-pastoral activities dating back to Neolithic. Moreover, the danger of losing oral traditions, and the increasing attention towards traditional remedies as potential sources of natural products for improving animal health and welfare, support the interest of our survey.

Phenolic Content, Antioxidant and Astroprotective Response to Oxidative Stress of Ethanolic Extracts of Mentha longifolia from Sinai

The aerial parts of Mentha longifolia L. are used as herbal remedies for curing different diseases through traditional Bedouin medicine. The antioxidant activity of the ethanolic extracts of M. longifolia was investigated measuring peroxyl radical-scavenging activity by ORAC assay, with Trolox (a water-soluble analogue of α-tocopherol) employed as reference compound. In addition, the total content of phenolic compounds estimated by the Folin-Ciocalteau method and the identification of the polyphenols using high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS) have been performed. Furthermore, the effect of these extracts on cell viability and intracellular ROS production was assayed using the U373-MG human astrocytoma cell line in a H2O2-induced oxidative stress model. Results showed that the major type of polyphenols found were benzoic acids, cinnamic acids, flavones and flavanones. The total phenolic content was 37.7 mg gallic acid/g sample and the ORAC value was 1.355 μmol TE/mg sample. The data obtained in cellular assays demonstrated that these ethanolic extracts protected H2O2-induced astrocyte damage by increasing cell viability and inhibiting production of intracellular ROS. These results suggest that the investigated extracts obtained from the aerial parts of M. longifolia have antioxidant potential related to their phenol content which have important beneficial health effects, especially in those disease associated with ROS.

In vitro antibacterial, antioxidant and cytotoxic activity of acetone leaf extracts of nine under-investigated Fabaceae tree species leads to potentially useful extracts in animal health and productivity

Background

The Fabaceae family is the second largest family of medicinal plants, containing more than 490 species which are being used as traditional medicine. The aim of this study was to determine the antioxidant and antibacterial activity as well as the cytotoxicity of acetone leaf extracts of nine tree species from the Fabaceae family that have not been investigated well previously for possible use in animal health and production.

Methods

The antibacterial activity was determined by a serial microdilution method against three Gram-positive and three Gram-negative bacteria. Antioxidant activity was determined using free-radical scavenging assays. The safety of the extracts was ascertained using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on Vero African green monkey kidney cells.

Results

Six of the nine acetone extracts had significant antibacterial activity against at least one of the six bacterial species with (MIC 20–80 μg/mL). The Crotalaria capensis extract had the highest activity against Salmonella typhimurium, followed by Indigofera cylindrica with MICs of 20 μg/mL and 40 μg/mL respectively. The Dalbergia nitidula extract had free radical scavenging capacity (IC₅₀ of 9.31 ± 2.14 μg/mL) close to that of the positive control Trolox in the DPPH assay. The Xylia torreana extract also had high activity (IC₅₀ of 14.56 ± 3.96 μg/mL) in the ABTS assay. There was a good correlation between antioxidant activity and total phenolic content (R² values > 0.8). The extracts had weak or no toxicity to Vero cells, compared to the positive control doxorubicin with the LC₅₀ varying from 10.70 ± 3.47 to 131.98 ± 24.87 μg/mL at the concentrations tested.

Conclusion

Extracts of D. nitidula, X. torreana, C. capensis and I. cylindrica had a low cytotoxicity and high antimicrobial and/or antioxidant activity. These species are therefore promising candidates for the development of useful antimicrobial/antioxidant preparations with a low cytotoxicity that may be useful in promoting animal health and productivity.