In Vitro α-Amylase and α-Glucosidase Inhibitory and Antioxidant Activities of the Crude Extract and Solvent Fractions of Hagenia abyssinica Leaves

BACKGROUND

The leaves of Hagenia abyssinica have been used in the management of diabetes mellitus in Ethiopian folk medicine. Thus, this study is aimed at investigating the in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the crude extract and solvent fractions of H. abyssinica leaves.

METHODS

The in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the plant extract were assessed using 3,5-dinitrosalicylic acid (DNSA), p-nitro-phenyl-a-D glucopyranoside (p-NPG), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, respectively. Each value of percent inhibition of α-amylase, α-glucosidase, and DPPH scavenging effect was presented as means ± SEM (n = 3).

RESULTS

The α-amylase inhibitory activity of the crude extract and solvent fractions was found to be concentration-dependent. The strongest activity was exhibited by the crude extract at the highest concentration with a percentage inhibition of 74.52% (IC50, 14.52 μg/ml) followed by water fraction 68.24% (IC50, 16.31 μg/ml), ethyl acetate fraction 61.57% (IC50, 18.73 μg/ml), and chloroform fraction 56.87% (IC50, 21.57 μg/ml) of H. abyssinica leaves. In the α-glucosidase inhibition assay, the maximum activity was exhibited by the aqueous fraction 62.54% (IC50, 11.67 μg/ml) followed by ethyl acetate fraction 54.97% (IC50, 15.89 μg/ml), crude extract 46.79% (IC50, >16.5 μg/ml), and chloroform fraction 36.44% (IC50, >16.5 μg/ml). In the antioxidant assay, the crude extract exhibited the highest antioxidant activity 86.36% (IC50, 10.25 μg/ml) followed by water fraction 78.59% (IC50, 13.86 μg/ml), ethyl acetate fraction 71.58% (IC50, 16.34 μg/ml), and chloroform fraction 63.65% (IC50, 18.83 μg/ml).

CONCLUSION

This study has revealed that H. abyssinica leaves possess noticeable in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities.

Inhibition of enzymes associated with metabolic and neurological disorder by dried pomegranate sheets as a function of pomegranate cultivar and fruit puree

BACKGROUND

Obesity and type 2 diabetes mellitus are the most extended current chronic diseases and also Alzheimer pathology which is a progressive degenerative neurological disorder. Therefore, finding effective enzyme inhibitors responsible for the development of these diseases are essential. Therefore, the aim of this study was to investigate the impact of fruit purée (Cydonia oblonga, Ziziphus jujube and Malus domestica) and pomegranate juice cultivar ('Mollar de Elche' and 'Wonderful') of dried pomegranate sheets (DS) on the inhibition of enzymes associated with metabolic (α-amylase, α-glucosidase, and pancreatic lipase activity), and neurological disorder (acetylcholinesterase and butyrylcholinesterase activity). Quality properties (colour coordinates, texture properties and sensory characteristics) of DS were also studied. In addition, it was researched the effect of storage conditions (4 months at 4 and 20 °C) on phenolic content.

RESULTS

DS from jujube had the highest antioxidant capacity and were characterized by the highest storage stability with respect to phenolic compounds. The α-amylase and α-glucosidase half maximal inhibitory concentration (IC₅₀ , in mg mL^-1 ) inhibition of DS ranged from 107 to 216 and from 55.2 to values indicating no effect, respectively. The inhibition toward pancreatic lipase (IC₅₀  < 5 mg mL^-1 ), acetylcholinesterase (ranged 9.15-22.2%) and butyrylcholinesterase (ranged 20.6-48.6%) was increased with the presence of total flavonoids and hydroxycinnamic acids content (identifying mainly in DS from quinces). It is noteworthy that none of the samples presented off-flavour notes, supporting the high quality of the products.

CONCLUSION

DS can be an innovative supplement to a diet as a snack used in the prevention of neurological changes and disorders of carbohydrate and lipid metabolism. © 2020 Society of Chemical Industry.

Antihypertensive and safety studies of Cydonia oblonga M

Antihypertensive studies on aqueous-methanolic extract prepared from seeds of Cydonia oblonga M. were carried out. The test extract in 200, 400 and 600 mg/kg doses was investigated in normotensive, high cholesterol and glucose fed hypertensive rats through non-invasive blood pressure measuring technique. Acute and sub-chronic toxicity studies were conducted in mice and rats, respectively. The test extract significantly decreased dose dependently the systolic, diastolic and mean arterial pressures. The test extract in 600mg/kg dose produced maximum effect and prevented rise in blood pressure of high cholesterol diet and glucose fed rats as compare to control in 21 days studies. The extract was found safe up to 4g/kg dose in mice. In sub-chronic toxicity study, no significant alteration in blood chemistry of extract treated rats was observed except reduction in the low density cholesterol levels. It is concluded that Cydonia oblonga seeds extract possess antihypertensive effect which supports its use in folklore.

Structural Changes in Milled Wood Lignin (MWL) of Chinese Quince (Chaenomeles sinensis) Fruit Subjected to Subcritical Water Treatment

Subcritical water treatment has received considerable attention due to its cost effectiveness and environmentally friendly properties. In this investigation, Chinese quince fruits were submitted to subcritical water treatment (130, 150, and 170 °C), and the influence of treatments on the structure of milled wood lignin (MWL) was evaluated. Structural properties of these lignin samples (UL, L130, L150, and L170) were investigated by high-performance anion exchange chromatography (HPAEC), FT-IR, gel permeation chromatography (GPC), TGA, pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS), 2D-Heteronculear Single Quantum Coherence (HSQC) -NMR, and 31P-NMR. The carbohydrate analysis showed that xylose in the samples increased significantly with higher temperature, and according to molecular weight and thermal analysis, the MWLs of the pretreated residues have higher thermal stability with increased molecular weight. The spectra of 2D-NMR and 31P-NMR demonstrated that the chemical linkages in the MWLs were mainly β-O-4' ether bonds, β-5' and β-β', and the units were principally G- S- H- type with small amounts of ferulic acids; these results are consistent with the results of Py-GC/MS analysis. It is believed that understanding the structural changes in MWL caused by subcritical water treatment will contribute to understanding the mechanism of subcritical water extraction, which in turn will provide a theoretical basis for developing the technology of subcritical water extraction.

Physical and Sensory Properties of Japanese Quince Chips Obtained by Osmotic Dehydration in Fruit Juice Concentrates and Hybrid Drying

Japanese quince has high health value, but due to its taste and texture, it is difficult to eat raw. The use of innovative drying methods to produce dried snack foods from these fruits may be of interest to producers and consumers. The physicochemical and sensory properties of 3 mm slices of Japanese quince fruit (with skin, without seeds) obtained by osmotic pre-treatment in chokeberry and apple juice concentrates, and with the use of convection (convective drying, C-D), freeze-drying (F-D), and convection-microwave-vacuum drying (hybrid) are assessed. The methods of drying osmo-dehydrated slices do not affect the dry matter content. In most dried quince, the water activity is 0.40 or lower. Pre-osmotic dehydration and drying have a significant impact on the mechanical and acoustic properties of quince chips. Sensory attractive chips emit loud acoustic emission (AE) during the breaking test. Chips that are osmo-dehydrated in a mixture of chokeberry juice concentrate and sucrose and dried by a hybrid method are attractive. They have a dark red color given by chokeberry concentrate and a slight sweet (with a slight sour-bitter) taste. The sensory evaluation was useful for determining the quality of the chips in terms of their texture (crispness) tested by mechanical methods. Their sensory ratings (overall desirability as weight of color, taste, crispness, and flavor) are high and similar (from 3.8 to 4.1). The use of innovative drying methods with pre-osmotic treatment allows obtaining dried material with properties comparable to those obtained by the F-D method, but in a much shorter time, i.e., with lower energy and using a simple method.

[Shikimic acid extracted from Chaenomeles speciosa reduces chondrocyte differentiation by inhibiting RBL-2H3 cell degranulation]

Objective To investigate the reducing effects of shikimic acid from the total extract of Chaenomeles speciose on the differentiation of chondrocytes into hypertrophic chondrocytes by inhibiting RBL-2H3 cell degranulation. Methods The chondrocytes were identified by toluidine blue staining and tryptase immunohistochemical staining. The chondrocytes were divided into normal chondrocytes control group, C48/80 activated RBL-2H3 cell culture supernatant treatment group, 3, 10 and 30 μg/mL SA activated RBL-2H3 cell culture supernatant treatment groups. The toxicity of SA and RBL-2H3 cell supernatant were detected by MTT assay. Western blotting was used to detect the expression of collagen type II (Col2) and collagen type X (Col10) in chondrocytes. The levels of matrix metalloproteinase 13 (MMP13), soluble nuclear factor B receptor activated protein ligand (sRANKL) and bone protective factor (OPG) were determined by ELISA, and glycosaminoglycan polysaccharide (GAG) were tested by dimethylmethylene blue (DMB) colorimetry. Results (0~30) μg/mL SA had no significant effects on the growth of chondrocytes. Compared with the C48/80 activated RBI-2H3 cell supernatant treatment group, the expression of Col2 and GAG proteins increased significantly, while the expression of Col10 and MMP13 and the ratio of sRANKL/OPG decreased significantly in the SA treatment groups in a dose-dependent manner. Conclusion SA can effectively reduce the differentiation of chondrocytes into hypertrophic chondrocytes by inhibiting RBL-2H3 cell degranulation.

Biological activity, phytochemical parameters, and potential bioaccessibility of wheat bread enriched with powder and microcapsules made from Saskatoon berry

The aim of the present study was to determine the impact of Saskatoon powder addition on phytochemical parameters, biological activity, and nutritional value of wheat bread. Supplementation increased phenolics content up to 72% in the bread with 6% powder content. This increase was reflected in the improved antioxidative properties of breads, especially after their supplementation with the microencapsulated additives (an increase by 93% in the bread enriched with 6% of powder covered with maltodextrin). The in vitro digestion released the antioxidative compounds, leading to higher bioaccessibility of the breads enriched with the microencapsulated powders. The highest inhibition of activities of cyclooxygenase 1 and -2, as well as amylase and glucosidase was recorded for the breads enriched with the additive microencapsulated with maltodextrin and inulin. Thus, Saskatoon berry powders, especially the microencapsulated ones, may be used as functional components in designing innovative bakery products.

Plant Extracts Containing Saponins Affects the Stability and Biological Activity of Hempseed Oil Emulsion System

In this study, two saponins-rich plant extracts, viz. Saponaria officinalis and Quillaja saponaria, were used as surfactants in an oil-in-water (O/W) emulsion based on hempseed oil (HSO). This study focused on a low oil phase content of 2% v/v HSO to investigate stable emulsion systems under minimum oil phase conditions. Emulsion stability was characterized by the emulsification index (EI), centrifugation tests, droplet size distribution as well as microscopic imaging. The smallest droplets recorded by dynamic light scattering (droplets size v. number), one day after the preparation of the emulsion, were around 50-120 nm depending the on use of Saponaria and Quillaja as a surfactant and corresponding to critical micelle concentration (CMC) in the range 0-2 g/L. The surface and interfacial tension of the emulsion components were studied as well. The effect of emulsions on environmental bacteria strains was also investigated. It was observed that emulsions with Saponaria officinalis extract exhibited slight toxic activity (the cell metabolic activity reduced to 80%), in contrast to Quillaja emulsion, which induced Pseudomonas fluorescens ATCC 17400 growth. The highest-stability samples were those with doubled CMC concentration. The presented results demonstrate a possible use of oil emulsions based on plant extract rich in saponins for the food industry, biomedical and cosmetics applications, and nanoemulsion preparations.

Osteomeles schwerinae Extract and Its Major Compounds Inhibit Methylglyoxal-Induced Apoptosis in Human Retinal Pigment Epithelial Cells

The accumulation and formation of advanced glycation end products (AGEs) are related to diabetes and age-related disease. Osteomeles schwerinae C. K. Schneid. (Rosaceae, OSSC) is used traditionally for the treatment of various diseases in Asia. Previous studies have shown that OSSC elicits preventive effects in an in vivo model of diabetes. This study was to evaluate the antiapoptotic effects of dried leaves and twigs of OSSC extract and its major compounds in ARPE-19 cells—spontaneously arising human retinal pigment epithelial cells—under diabetic conditions. To examine the effects of an OSSC extract and its active compounds (acetylvitexin, hyperoside and quercitrin) on apoptosis in methylglyoxal (MG, the active precursor in the formation of AGEs)-treated ARPE-19 cells and the mechanism by which these effects occur, apoptosis was measured using flow cytometry analysis. Protein expression levels of phospho-p53 (p-p53), Bax and Bcl-2 were determined by western blot analyses. The OSSC extract inhibited apoptosis in MG-treated ARPE-19 cells in a dose-dependent manner. The major compounds also reduced the rate of apoptosis. Both the extract and major compounds also inhibited the expression of p-p53 and Bax and increased the levels of Bcl-2 that had been previously reduced by MG treatment. The OSSC extract (0.1 μg/mL) and its major compounds (0.01 μM) attenuated apoptosis in ARPE-19 cells under toxic diabetic conditions by downregulating of expression of p-p53 and Bax. OSSC may serve as an alternative therapy to retard the development of diabetic retinopathy.

Inactivation and structural changes of polyphenol oxidase in quince (Cydonia oblonga Miller) juice subjected to ultrasonic treatment

BACKGROUND

Polyphenol oxidase (PPO) is considered a problem in the food industry because it starts browning reactions during fruit and vegetable processing. Ultrasonic treatment is a technology used to inactivate the enzyme; however, the mechanism behind PPO inactivation is still unclear. For this reason, the inactivation, aggregation, and structural changes in PPO from quince juice subjected to ultrasonic treatments were investigated. Different intensities and times of ultrasonic treatment were used. Changes in the activity, aggregation, conformation, and structure of PPO were investigated through different structural analyses.

RESULTS

Compared to untreated juice, the PPO activity in treated juice was reduced to 35% at a high ultrasonic intensity of 400 W for 20 min. The structure of PPO determined from particle size distribution (PSD) analysis showed that ultrasound treatment caused initial dissociation and subsequent aggregation leading to structural modification. The spectra of circular dichroism (CD) analysis of ultrasonic treated PPO protein showed a significant loss of α-helix, and reorganization of secondary structure. Fluorescence analysis showed a significant increase in fluorescence intensity of PPO after ultrasound treatment with evident blue shift, revealing disruption in the tertiary structure.

CONCLUSION

In summary, ultrasonic treatment triggered protein aggregation, distortion of tertiary structure, and loss of α-helix conformation of secondary structure causing inactivation of the PPO enzyme. Hence, ultrasound processing at high intensity and duration could cause the inactivation of the PPO enzyme by inducing aggregation and structural modifications. © 2019 Society of Chemical Industry.

Saskatoon Berry Amelanchier alnifolia Regulates Glucose Metabolism and Improves Cardiovascular and Liver Signs of Diet-Induced Metabolic Syndrome in Rats

Saskatoon berry (Amelanchier alnifolia) is a potential functional food containing anthocyanins and flavonols, as well as ellagitannins and phenolic acids. We have determined the potential therapeutic effects of Saskatoon berry in diet-induced metabolic syndrome. Nine- to ten-week-old male Wistar rats were randomly assigned to four groups. Two groups were fed on control diets, either corn starch (C) or high-carbohydrate, high-fat diet (H) respectively, for 16 weeks. Two further groups were fed on C or H diet for 16 weeks with Saskatoon berry powder added to the diet for the final 8 weeks (CSSK, HSSK). After 16 weeks, H rats showed symptoms of metabolic syndrome, including increased body weight, visceral adiposity, systolic blood pressure, cardiac fibrosis, plasma concentrations of triglycerides and non-esterified fatty acids, and plasma activities of alanine transaminase and aspartate transaminase. Saskatoon berry intervention normalised body weight and adiposity, improved glucose tolerance, decreased systolic blood pressure, improved heart and liver structure and function with decreased infiltration of inflammatory cells, and decreased plasma total cholesterol. Further, Saskatoon berry normalised liver expression of hexokinase 1 and glycogen phosphorylase and increased glucose 6-phosphatase relative to H rats. These results suggest that Saskatoon berry regulates glycolysis, gluconeogenesis and glycogenesis to improve metabolic syndrome.

Green Synthesis of Gold Nanoparticles Capped with Procyanidins from Leucosidea sericea as Potential Antidiabetic and Antioxidant Agents

In this study, procyanidins fractions of dimers and trimers (F1-F2) from the Leucosidea sericea total extract (LSTE) were investigated for their chemical constituents. The total extract and the procyanidins were employed in the synthesis of gold nanoparticles (Au NPs) and fully characterized. Au NPs of 6, 24 and 21 nm were obtained using LSTE, F1 and F2 respectively. Zeta potential and in vitro stability studies confirmed the stability of the particles. The enzymatic activity of LSTE, F1, F2 and their corresponding Au NPs showed strong inhibitory alpha-amylase activity where F1 Au NPs demonstrated the highest with IC₅₀ of 1.88 µg/mL. On the other hand, F2 Au NPs displayed the strongest alpha-glucosidase activity at 4.5 µg/mL. F2 and F2 Au NPs also demonstrated the highest antioxidant activity, 1834.0 ± 4.7 μM AAE/g and 1521.9 ± 3.0 μM TE/g respectively. The study revealed not only the ability of procyanidins dimers (F1 and F2) in forming biostable and bioactive Au NPs but also, a significant enhancement of the natural products activities, which could improve the smart delivery in future biomedical applications.

Anti-inflammatory effects of Sarcopoterium spinosum extract

ETHNOPHARMACOLOGICAL RELEVANCE

Sarcopoterium spinosum is a Mediterranean plant, widely used by the Beduin traditional medicine. While its major use is for the treatment of diabetes, there are also documentations for its use as anti-inflammatory agent. This therapeutic potential of Sarcopoterium spinosum was not validated before.

AIM OF THE STUDY

To investigate the anti-inflammatory properties of Sarcopoterium spinosum extract (SSE).

MATERIALS AND METHODS

Experiments were performed on RAW264.7 macrophages and bone marrow-derived macrophages (BMDM) and the effect of SSE on markers of inflammation was investigated. In addition, the effect of SSE on the development of inflammation in adipose-tissue of obese, insulin resistant mice was measured in KK-Ay mice and high fat diet (HFD)-fed mice.

RESULTS

Lipopolysaccharide (LPS) and SSE increased the viability of RAW264.7. In addition, the cells acquired distinct dendritic-like morphology, however, while LPS induced NO production and the mRNA expression of pro-inflammatory cytokines, SSE increased the mRNA expression of anti-inflammatory genes and blocked LPS effects. All three pathways of MAPK were activated by LPS and SSE, as demonstrated by the phosphorylation of ERK, p38 and JNK. NFκB was activated and Akt was phosphorylated by LPS, while SSE blocked this effects. STAT proteins were differently phosphorylated by SSE and LPS. Immunomodulatory effects of SSE were also found in BMDM. In adipose tissue of SSE-treated mice, less crown-like structures were found, and lower expression of pro-inflammatory adipocytokines was observed, although adipocytes hypertrophy was not affected.

CONCLUSIONS

SSE has an immunomodulatory effects that affect macrophage function, and reduces adipose tissue inflammation. Identifying active component and clarifying its mechanism of action might support the development of new anti-inflammatory agent.

Microbiological, antioxidant and lipoxygenase-1 inhibitory activities of fruit extracts of chosen Rosaceae family species

BACKGROUND

Extracts from the Rosaceae family fruits are rich in natural, biologically active polyphenols, but their antibacterial properties are still poorly understood. Therefore, we focused our research on their activity against uropathogenic Escherichia coli strains. This research also concerned the proof of their ability to reduce oxidative stress and modulate the activity of lipoxygenase-1 (LOX-1). It is well-known that plants represent a source of bioactive compounds whose antioxidant activity may be useful in protecting against oxidative damage in cells, which have been linked to the pathogenesis of many oxidative diseases.

OBJECTIVES

The study determined the biological activity of methanol (ME) and water (WE) extracts rich in polyphenols from the hawthorn (Crataegus monogyna Jacq.), dog rose (Rosa canina L.), quince (Cydonia oblonga Mill.), and Japanese quince (Chaenomeles speciosa (Sweet) Nakai).

MATERIAL AND METHODS

The antioxidant capacity was evaluated using 1,1diphenyl-2-picrylhydrazyl (DPPH▪) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS+▪) radical scavenging methods. The inhibition of liposome membrane oxidation was studied using the thiobarbituric acid reactive substances assay. Lipoxygenase-1 inhibitory activity was measured using the spectrophotometric method. Bacterial growth was determined by evaluating the number of colony forming units per milliliter (CFU/mL). Hydrophobicity was established with salt aggregation hydrophobicity test (SAT). Swimming and swarming motilities were evaluated using soft-agar plates. Production of curli fimbriae was estimated on CFA agar. The P fimbriae were detected using the hemagglutination of erythrocytes. Adhesion of bacteria to human uroepithelial cells was assessed. The amount of biofilm was determined spectrophotometrically.

RESULTS

We showed that most of these extracts are effective antioxidants and free radical scavengers, possess reasonable potential anti-inflammatory activity, reduce the adhesion of E. coli to uroepithelial cells, and reduce the ability of these bacteria to form biofilm.

CONCLUSIONS

The extracts examined, showing very promising biological properties, seem to be able to join the list of substances that can be used as dietary supplements aimed at preventing, for example, urinary tract infections, or as support of drug treatment in many diseases.

Exploring the metabolomic diversity of plant species across spatial (leaf and stem) components and phylogenic groups

BACKGROUND

Plants have been used as an important source of indispensable bioactive compounds in various cosmetics, foods, and medicines. However, the subsequent functional annotation of these compounds seems arduous because of the largely uncharacterized, vast metabolic repertoire of plant species with known biological phenotypes. Hence, a rapid multi-parallel screening and characterization approach is needed for plant functional metabolites.

RESULTS

Fifty-one species representing three plant families, namely Asteraceae, Fabaceae, and Rosaceae, were subjected to metabolite profiling using gas chromatography time-of-flight mass spectrometry (GC-TOF-MS) and ultrahigh-performance liquid chromatography quadrupole orbitrap ion trap tandem mass spectrometry (UHPLC-Q-orbitrap-MS/MS) as well as multivariate analyses. Partial least squares discriminant analysis (PLS-DA) of the metabolite profiling datasets indicated a distinct clustered pattern for 51 species depending on plant parts (leaves and stems) and relative phylogeny. Examination of their relative metabolite contents showed that the extracts from Fabaceae plants were abundant in amino acids, fatty acids, and genistein compounds. However, the extracts from Rosaceae had higher levels of catechin and ellagic acid derivatives, whereas those from Asteraceae were higher in kaempferol derivatives and organic acids. Regardless of the different families, aromatic amino acids, branch chain amino acids, chlorogenic acid, flavonoids, and phenylpropanoids related to the shikimate pathway were abundant in leaves. Alternatively, certain amino acids (proline, lysine, and arginine) as well as fatty acids levels were higher in stem extracts. Further, we investigated the associated phenotypes, i.e., antioxidant activities, affected by the observed spatial (leaves and stem) and intra-family metabolomic disparity in the plant extracts. Pearson's correlation analysis indicated that ellagic acid, mannitol, catechin, epicatechin, and quercetin derivatives were positively correlated with antioxidant phenotypes, whereas eriodictyol was positively correlated with tyrosinase inhibition activity.

CONCLUSIONS

This work suggests that metabolite profiling, including multi-parallel approaches and integrated bioassays, may help the expeditious characterization of plant-derived metabolites while simultaneously unraveling their chemodiversity.

Bioactive Components and Health Benefits of Saskatoon Berry

In response to the recent rise in numbers of diabetes patients, many treatments have been developed; but currently, oral antihyperglycemic agents and insulin are still the main clinical treatments. Since current drugs have limitations and harmful side effects, research in alternative treatments has been sought. This article reviews recent research updates of Saskatoon berries (SB), covering its background information, its main active ingredients, its structure, and its function. Flavonoid compounds in Saskatoon berries, in particular flavanol, anthocyanin, and proanthocyanin, possess anti-inflammatory, antitumor, and antidiabetes impacts. The current review synthesizes the latest research on the health benefits of Saskatoon berry in a variety of domains. With further research, SB has the potential to help treat and prevent diabetes in the future.

Duchesnea indica extract attenuates oral cancer cells metastatic potential through the inhibition of the matrix metalloproteinase-2 activity by down-regulating the MEK/ERK pathway

BACKGROUND

Duchesnea indica (Andr.) Focke, an herb in folk medicine used extensively in traditional Chinese medicine, has cytostatic properties as well as antioxidant and antimetastasis activities in various cancer cells. However, the effects and underlying mechanisms of Duchesnea indica extracts (DIEs) on human oral squamous cell carcinoma (OSCC) metastases remain unclear.

PURPOSE

In this study, we posit the hypothesis that DIE possesses antimetastatic effects on human OSCC cells.

METHODS

The effects of DIE on cell viability, motility, migration, and invasion were investigated. Gelatin zymography, Western blotting, migration and invasion assays were used to further study the underlying mechanisms involved in the antimetastatic effects of DIE in OSCC cells.

RESULTS

The results from MTT assay revealed that DIE did not affect the cell viability of OSCC cells. Moreover, DIE significantly attenuated OSCC cells' motility, migration, and invasion by reducing the MMP-2 protein expression and MMP-2 activity in a dose-dependent manner. In addition, DIE reduced the phosphorylation of both ERK1/2 and its upstream kinase but had no effect on the phosphorylation of p38 and JNK.

CONCLUSION

DIE triggers the antimetastatic activity in OSCC cells by suppressing the MMP-2 activity via the MEK/ERK signaling pathways. Therefore, these findings are promising for the use of DIE antimetastatic activity in oral cancer metastasis treatment.

Activation of Insulin Signaling in Adipocytes and Myotubes by Sarcopoterium Spinosum Extract

Sarcopoterium spinosum (S. spinosum) is a medicinal plant, traditionally used as an antidiabetic remedy. Previous studies demonstrated its beneficial properties in the treatment of insulin resistance. The aim of this study was to further clarify the effect of S. spinosum extract (SSE) on insulin signaling. Phosphoproteomic analysis, performed in 3T3-L1 adipocytes treated with SSE, revealed the activation of insulin receptor pathways. SSE increased Glut4-facilitated glucose uptake in adipocytes, with an additive effect between SSE and insulin. While the maximal effect of insulin on glucose uptake was found at days 15–16 of differentiation, SSE-induced glucose uptake was found at an earlier stage of differentiation. Inhibition of PI3K and Akt blocked SSE-dependent glucose uptake. Western blot analysis, performed on 3T3-L1 adipocytes and L6 myotubes, showed that in contrast to insulin action, Akt was only marginally phosphorylated by SSE. Furthermore, GSK3β and PRAS40 phosphorylation as well as glucose uptake were increased by the extract. SSE also induced the phosphorylation of ERK similar to insulin. In conclusion, SSE activates insulin signaling, although the upstream event mediating its effects should be further clarified. Identifying the active molecules in SSE may lead to the development of new agents for the treatment of insulin resistance.

Neutralization of cholera toxin by Rosaceae family plant extracts

BACKGROUND

Cholera is one of the most deadly diarrheal diseases that require new treatments. We investigated the neutralization of cholera toxin by five plant extracts obtained from the Rosaceae family that have been traditionally used in Poland to treat diarrhea (of unknown origin).

METHODS

Hot water extracts were prepared from the dried plant materials and lyophilized before phytochemical analysis and assessment of antimicrobial activity using microdilution assays. The ability of the plant extracts to neutralize cholera toxin was analyzed by measurement of cAMP levels in cell cultures, enzyme-linked immunosorbent assay and electrophoresis, as well as flow cytometry and fluorescence microscopy studies of fluorescent-labeled cholera toxins with cultured human fibroblasts.

RESULTS

The antimicrobial assays displayed modest bacteriostatic potentials. We found that the plant extracts modulate the effects of cholera toxin on intracellular cAMP levels. Three plant extracts (Agrimonia eupatoria L., Rubus fruticosus L., Fragaria vesca L.) suppressed the binding of subunit B of cholera toxin to the cell surface and immobilized ganglioside GM1 while two others (Rubus idaeus L., Rosa.canina L.) interfered with the toxin internalization process.

CONCLUSIONS

The traditional application of the Rosaceae plant infusions for diarrhea appears relevant to cholera, slowing the growth of pathogenic bacteria and either inhibiting the binding of cholera toxin to receptors or blocking toxin internalization. The analyzed plant extracts are potential complements to standard antibiotic treatment and Oral Rehydration Therapy for the treatment of cholera.

Preventive effect of purgative manna on neonatal jaundice: A double blind randomized controlled clinical trial

ETHNOPHARMACOLOGICAL RELEVANCE

Cotoneaster nummularioides Pojark manna (Shir-e-Khesht) is popular in Persian medicine. Different effects of some Cotoneaster species manna include antibacterial, antioxidant, anticancer, and hepatoprotective effects, as well as bilirubin serum levels reduction. Cotoneaster species manna is used in many parts of Iran as a laxative and accelerates the passage of meconium. Neonatal jaundice has relatively costly and sometimes invasive therapeutic interventions, which its prevention from becoming severe cases can be a priority in neonatal medicine.

AIM OF THE STUDY

The aim of this study was to evaluate the effectiveness of an herbal product (Purgative Manna, native to Iran and Asian countries) in preventing severe cases of jaundice and reducing total bilirubin levels in neonates.

MATERIALS AND METHODS

This randomized double-blind controlled clinical trial included full-term babies. Four hundred and forty-five (445) eligible neonates were assigned to two groups using the block balanced randomization method; 222 neonates received the Purgative Manna product as drops, and 223 neonates received placebo drops. The neonates received a dose of 5 drops per kilogram of neonatal weight (divided into three doses per day) for three days. The treatment period was three days, and a 24-h (three times) examination was performed to measure the initial outcome of the trial (i.e., the total serum bilirubin level). The secondary outcomes of this trial were the need for hospitalization due to jaundice and/or phototherapy from 4 to 14 days after birth, the frequency of defecation within 24 h, and the triple complications of diarrhoea, dehydration symptoms, and abdominal colic.

RESULTS

In this study, 220 neonates in the Purgative Manna product group and 222 neonates in the placebo group completed their interventions within the predicted period of the study. At the end of study, the total bilirubin level in the Purgative Manna treated group was significantly lower than that of the placebo group. The difference between the mean total bilirubin levels of the two groups was approximately 2.1 mg/dl on the third day after treatment, with an effect size of 0.79 (95% CI: 0.06-0.98). The relative risk for reducing the need for hospitalization or phototherapy in the group treated with Purgative Manna drops was 0.26, compared with the placebo group. The risk of occurrence of severe jaundice or phototherapy in the Purgative Manna group was 75% lower than that of the placebo group. The median frequency of defecation in the intervention group at three time intervals in the first, second and third days after treatment was 1-2 times more than that of the comparison group (p < 0.001).

CONCLUSIONS

Meanwhile, considering the fact that one in every eight neonates who used the product avoided having a severe and high-risk case of jaundice or the need for phototherapy intervention (even through an exchange transfusion), the use of Purgative Manna drops can be recommended; however, further study is necessary.

Effect of processing on quality attributes and phenolic profile of quince dried bar snack

BACKGROUND

Fruit and vegetable processing can often alter and damage antioxidants. Phenolic compounds, which are major antioxidants in these products, can suffer dissociation and changes in their concentration. Quince is an excellent source of antioxidants, with health-improving potential for consumers. The phenolic profile (by ultra-high-performance liquid chromatography-mass spectrometry) and quality attributes (pH, soluble solids, acidity, water activity) were determined for processed quince products (fresh fruit puree, cooked puree and dried bars), in addition to the effect of puree cooking time (5, 10, 15 and 20 min).

RESULTS

Soluble solids in purees averaged 14.4 °Brix and increased to 75 °Brix in bars, as did titratable acidity, reaching 1.5 g malic acid kg^-1 fresh weight after 20 min of cooking at 120 °C. Quercetin, p-coumaric acid and trans-cinnamic acid were predominant in fresh fruit puree. Thermal processing significantly increased the concentration of p-coumaric acid, trans-cinnamic acid, apigenin and quercetin, and decreased gallic acid. This increase was 242%, on average, for all of them when comparing fresh fruit puree with bars on a fresh weight basis, demonstrating their concentration throughout the dehydration process during bar production.

CONCLUSION

Although a minimum puree cooking time of 5 min was sufficient to obtain the highest concentration of most phenolics, p-coumaric acid showed a higher concentration after 20 min of cooking. © 2018 Society of Chemical Industry.

Preliminary evaluation of quince (Cydonia oblonga Mill.) fruit as extraction source of antioxidant phytoconstituents for nutraceutical and functional food applications

BACKGROUND

Quince (Cydonia oblonga) fruits can be considered as starting material for the extraction of health-promoting phytochemicals, to be exploited in food and nutraceuticals. In the present work, liquid chromatography coupled with diode array detection and tandem mass spectrometry analysis allowed the study of the phytochemical composition of quince fruits and to compare it with those of six commercial apple varieties.

RESULTS

The distribution and quantification of secondary metabolites in peel and pulp were studied and compared with six commercial apple varieties. Furthermore the in vitro antioxidant activity was determined by 2,2-diphenyl-2-picrylhydrazyl (DPPH) assay. Quince fruit presented significant amounts of shikimic and quinic acid derivatives, as well as flavonoids and procyanidins. Compared with apple, quince fruit composition was characterized by the presence of 4-caffeoylshikimic acid, 4-caffeoyl quinic acid, quercetin-3,7-diglucoside, kaempferol-3-O-rhamnoside and kaempferol-7-O-glucoside, and the dihydrochalcones were not detectable. The peel showed the highest contents of phenolics, whereas 3-O-caffeoylquinic acid was the most abundant compound in the quince pulp. The Pearson correlation index was calculated considering the quantitative amount of the phenolic constituents and the radical scavenging activity toward DPPH^· both for peel and pulp extracts.

CONCLUSIONS

This study highlighted the presence of significant amounts of valuable secondary metabolites in quince fruit, in particular the procyanidins and caffeoyl esters with shikimic and quinic acid. Notably, owing to the higher content in phenolic compounds and the stronger antioxidant capacity compared with the other fruits considered, the use of C. oblonga as a source of antioxidant can be valuable in nutraceuticals, revealing new possible applications of quince fruit. © 2018 Society of Chemical Industry.

Characterizations and rheological study of the purified polysaccharide extracted from quince seeds

BACKGROUND

The functional characteristics of hydrocolloids are mainly dependent on their physicochemical properties. Thus, it is essential to characterize the new sources of hydrocolloids.

RESULTS

Quince seed gum (QSG) is a high-molecular-weight polysaccharide (9.61 × 10⁶  g mol^-1 ) composed of 85.04 ± 2.87% carbohydrate (6.39% l-arabinose, 40.43% d-xylose, 5.60% d-galactose, 5.75% d-glucose and 31.11% d-mannose), 13.16 ± 1.73% uronic acid, 5.77 ± 0.83% moisture, 2.78 ± 0.21% protein, 5.64 ± 0.21% ash, and 0.75 ± 0.09% fat. Our findings indicated that this gum could be introduced as a value-added by-product in the food and pharmaceutical industries. Carbon-13 nuclear magnetic resonance and Fourier transform infrared spectroscopy suggested a highly substituted xylan structure for QSG. In the dilute regime, an increase in the ion concentration was accompanied by a decrease in intrinsic viscosity of QSG. When the salt concentration increased from 0 to 50 mmol L^-1 , the consistency coefficient (as a measure of apparent viscosity) declined. On the other hand, with further increasing of salt concentration, the consistency coefficient (as a measure of apparent viscosity) values increased. Similarly, the G' and G″ values for 10 and 50 mmol L^-1 calcium chloride concentrations were less than in control samples.

CONCLUSION

The rheological behavior of the QSG studied in this paper can provide insight into its potential application in food and pharmaceutical industries. © 2018 Society of Chemical Industry.

Phytochemical composition of smoothies combining pomegranate juice (Punica granatum L) and Mediterranean minor crop purées (Ficus carica, Cydonia oblonga, and Ziziphus jujube)

BACKGROUND

Daily intake of fruits and vegetables as suggested by the World Health Organization is lower than the recommended dietary intake (RDI). A good option to increase the intake of fruit and vegetables is the consumption of smoothies. This work evaluated the effect of adding fig, jujube or quince purée to pomegranate juice (cultivars 'Wonderful' and 'Mollar de Elche') in preparing smoothies at two ratios of purée:juice (40:60 and 60:40) on the composition of minerals, sugars, organic acids, vitamin C, antioxidant activity and polyphenols.

RESULTS

Smoothies composition was mainly affected by the addition of the fruit purée. Twenty-eight polyphenolic compounds were found in the pomegranate smoothies (quadrupole time-of-flight liquid chromatography-mass spectrometry). The highest total content of polyphenolic compounds (ultra-performance liquid chromatography with photodiode array and fluorescence detection) was found in smoothies with quince purée, 501 mg 100 g^-1 fresh weight (FW), followed by jujube and figs, with 374 and 320 mg 100 g^-1 FW, respectively. Fig smoothies were rich in anthocyanins, while the jujube ones had high content of flavonols and vitamin C; finally, the quince smoothies were rich in hydroxycinnamic acids.

CONCLUSION

A positive effect of the addition of minor crops (fig, jujube and quince) was observed on the nutritional and functionality of the novel pomegranate smoothies. Moreover, the addition of jujube contributed to an enrichment of the final smoothies in vitamin C and organic acids, while an increase of pectin content was found in fig and quince pomegranate based smoothies. Therefore, the blend of minor Mediterranean crop purées with pomegranate juice to produce smoothies is a good strategy to promote the consumption of these healthy but underutilized fruits. © 2018 Society of Chemical Industry.

Effect of Pentacyclic Triterpenoids-Rich Callus Extract of Chaenomeles japonica (Thunb.) Lindl. ex Spach on Viability, Morphology, and Proliferation of Normal Human Skin Fibroblasts

The effect of the well-characterized callus extract of Chaenomeles japonica on viability, morphology, and proliferation of normal human skin fibroblasts was investigated. The phytochemical analysis was performed using the ultra-high performance liquid chromatography method. The total phenolic, phenolic acid, and flavonoid contents were determined spectrophotometrically. The antioxidant activity was investigated using the DPPH (1,1-Diphenyl-1-picrylhydrazyl Radical Scavenging), FRAP (Ferric Reducing Antioxidant Power), and CUPRAC (CUPric Reducing Antioxidant Capacity) assays. The callus growth index during passages was high as well as the content of pentacyclic triterpenoids. The microscopic observations of the fibroblast viability, morphology and the evaluation of the proliferation ratio (xCELLigence system) proved that the influence of callus extract on the fibroblasts was dose-dependent. The evaluated level of fibroblasts proliferation rate after 72 h of incubation with callus extract at concentration 12.5 µg L⁻¹ was the highest compared to all the analyzed ligands. Moreover, callus extract administrated for 72 h caused a significant increase in the proliferation rate in comparison with the control group (5.7 ± 0.1 vs. 4.4 ± 0.9; p < 0.01). The preliminary studies carried out may suggest that the callus extract rich in triterpenoids may be a potential source of cosmetic ingredients with a beneficial effect on human skin.