Nanoemulsion and nanoencapsulation of a hydroethanolic extract of Nettle (Urtica dioica) and Wormwood (Artemisia absinthium): comparison of antibacterial and anticancer activity

Introduction: Nanoemulsion and nanoencapsulation are attractive novel methods that can be used for incorporating active plant extracts in food preparations and pharmaceutical formulations. In the current study, we aimed to investigate the anticancer and antibacterial effects of hydroethanolic extracts of Nettle (NE), Wormwood (WE), and the combination of the two plants (CNWE), as well as their nanoemulsion forms (NN, NW, CNNW) and nanoencapsulation forms (CN, CW, and CCNW). Methods: The morphology and structure of the nanoemulsion and nanoencapsulation preparations were assessed utilizing dynamic light scattering (DLS) along with transmission electron microscopy (TEM). The antibacterial activity of the prepared formulations were assessed by determining minimum inhibitory concentration (MIC), zone of inhibition diameter, minimum bactericidal concentration (MBC), along with biofilm growth inhibition against Salmonaella typhimurium and Klebsiella. pneumoniae. The anticancer activity was evaluated via a MTT assay in the colon cancer cell line (HCT116). Results: The nanoemulsion and nanoencapsulation particle size varied between 10 and 50 nm and 60 and 110 nm, respectively. The MIC values were between 11.25 and 95 µg/mL along with MBC values between 11.25 and 190 µg/mL. The highest inhibition of biofilm formation was observed with CCNW against K. pneumoniae (∼78.5%) and S. typhimurium (∼73%). In descending order, the inhibition of biofilm formation was CCNW > CW > CN > CNNW > NN > NW > CNWE > NE > WE against the tested bacteria. The IC50 values for NE, WE, CNWE, NN, NW, CNNW, CN, CW, and CCNW were determined as 250, 170, 560, 380, 312, 370, 250, 420, and 700 µg/mL, respectively. Exposure to a high concentration of NW resulted in a significantly lower HCT116 viability compared to other groups. Taken together, CNNW, and CCNW showed the highest antibacterial and anticancer activitiy. Discussion: Nanoemulsion and nanoencapsulation were effective ways to increase the antibacterial and anticancer activity of the extracts and could be used in the food and pharmaceutical industries.

Beneficial Effects of Algerian Green Alga Ulva lactuca and Its Hydroethanolic Extract on Insulin Resistance and Cholesterol Reverse Transport in High-Fat/Streptozotocin Diabetic Rats

The aim of this study was to evaluate the impact of the green algae Ulva lactuca and its hydroethanolic extract on insulin resistance and cholesterol reverse transport in type 2 diabetic (T2D) rats. Rats had T2D induced by a high-fat diet (HFD) for 5 weeks followed by intraperitoneal injection of streptozotocin. Diabetic rats were divided into three groups and were fed a HFD in the presence or absence of 1% alga (HFD-Alg) or 1% of its hydroethanolic extract (HFD-Ext), for 4 weeks. The control group consumed 20% casein combined with 5% lipids. Hyperglycemia, insulin resistance, hypercholesterolemia, and hypertriglyceridemia were noted in HFD rats vs control rats. Whole alga and its extract decreased these parameters vs the HFD. Moreover, fecal total cholesterol and triacylglycerols levels were lowered in HFD group vs C group, but were increased with HFD-Alg vs HFD. Compared with the Control, the HFD group had decreased lecithin:cholesterol acyltransferase (LCAT) activity, apolipoprotein A-I (ApoA-I), high-density lipoprotein (HDL₃)-phospholipids (PL), and HDL₂-cholesteryl ester (CE) levels, but increased HDL₃-unesterified cholesterol (UC) levels. Furthermore, compared with the HFD group, the HFD-Alg and HFD-Ext groups had increased LCAT activity, ApoA-I, HDL₃-PL, and HDL₂-CE levels and decreased HDL₃-UC levels. In addition, in the HFD-Ext group, LCAT activity and ApoA-1 levels were decreased vs the HFD-Alg whereas HDL₃-UC levels were increased. In conclusion, these results indicate that U. lactuca and its hydroethanolic extract have curative effect on T2D. Therefore, this alga could be considered a functional food supplement for the treatment and prevention of diabetes.

Thymus zygis subsp. zygis an Endemic Portuguese Plant: Phytochemical Profiling, Antioxidant, Anti-Proliferative and Anti-Inflammatory Activities

Thymus zygis subsp. zygis is an endemic Portuguese plant belonging to the Thymus zygis species. Although T. zygis is commonly used as a condiment and as a medicinal herb, a detailed description of the polyphenol composition of hydroethanolic (HE) and aqueous decoction (AD) extracts is not available. In this work, we describe for the first time a detailed phenolic composition of Thymus zygis subsp. zygis HE and AD extracts, together with their antioxidant, anti-proliferative and anti-inflammatory activities. Unlike other Thymus species, T. zygis subsp. zygis extracts contain higher amounts of luteolin-(?)-O-hexoside. However, the major phenolic compound is rosmarinic acid, and high amounts of salvianolic acids K and I were also detected. T. zygis subsp. zygis extracts exhibited significant scavenging activity of ABTS⁺, hydroxyl (^•OH), and nitric oxide (NO) radicals. Regarding the anti-proliferative/cytotoxic effect, tested against Caco-2 and HepG2 cells, the AD extract only slightly reduced cell viability at higher concentrations (IC₅₀ > 600 µg/mL, 48 h exposure), denoting very low toxicity, while the HE extract showed a high anti-proliferative effect, especially at 48 h exposure (IC₅₀ of 85.01 ± 15.10 μg/mL and 82.19 ± 2.46 μg/mL, for Caco-2 and HepG2, respectively). At non-cytotoxic concentrations, both extracts reduced the nitric oxide (NO) release by lipopolysaccharide (LPS)-stimulated RAW 264.7 cells (at 50 μg/mL, HE and AD extracts inhibited NO release in ~89% and 48%, respectively). In conclusion, the results highlight the non-toxic effect of aqueous extracts, both resembling the consumption of antioxidants in foodstuff or in functional food. Furthermore, the HE extract of T. zygis subsp. zygis is a source of promising molecules with antioxidant, anti-inflammatory and anticancer activities, highlighting its potential as a source of bioactive ingredients for nutraceutical and pharmaceutical industries.

Chemical Characterization and Bioactivity of Extracts from Thymus mastichina: A Thymus with a Distinct Salvianolic Acid Composition

Thymus mastichina, also called mastic thyme or Spanish marjoram, is endemic to the Iberian Peninsula, where it is widely used in folk medicine especially for treating digestive and respiratory systems disorders, and as a condiment to season olives. This work describes for the first time the detailed phenolic composition of exhaustive hydroethanolic extracts and aqueous decoctions of Thymus mastichina. Unlike other species of the Thymus genera, Thymus mastichina extracts contain high amounts of salvianolic acid derivatives, with salvianolic acid A isomer being the main derivative. This isomer was identified in extracts from Thymus mastichina for the first time. Also, an undescribed salvianolic acid derivative in Thymus mastichina was identified and its structure was tentatively described. Extracts from Thymus mastichina showed significant scavenging activity of 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical cation, hydroxyl, and nitric oxide radicals. The anti-proliferative effect of both T. mastichina extracts were tested against Caco-2 and HepG2 cells; the hydroethanolic extract showed a high anti-proliferative activity against Caco-2 cells compared to HepG2 cells (at 24 h exposure, the concentration that inhibits 50% of proliferation, IC₅₀, was 71.18 ± 1.05 µg/mL and 264.60 ± 11.78 µg/mL for Caco-2 and HepG2, respectively). Thus, these results make this species a promising candidate for further investigation of its anti-tumoral potential. Therefore, Thymus mastichina can be potentially used as a functional food (used as a decoction or herbal tea) or as a source of bioactive ingredients with antioxidant and anti-proliferative properties.

Effect of Poria cocos hydroethanolic extract on treating adriamycin-induced rat model of nephrotic syndrome

OBJECTIVE

To evaluate the effect of Poria cocos (Schw.) Wolf hydroethanolic extract (PHE) against nephrotic syndrome (NS) in rats and to identify the potential active components from PHE.

METHODS

The high content compounds were isolated and purified by using column chromatography followed by preparative highperformance liquid chromatography (p-HPLC). Forty male Wistar rats with adriamycin (ADR)-induced NS were randomly divided into 5 groups, 8 in each group: model control group, positive control group (with prednisone treatment), PHE low-dose group, PHE middle-dose group and PHE high-dose group. Another 8 rats were recruited as vehicle control group. All rats received the intragastric administration of corresponding drugs or saline for 30 days. During the experimental period, rats' behavior and appearance were observed and recorded daily, and their body weights were recorded weekly. After treatment, 24-h urine samples were collected to evaluate the urine protein and urine creatinine (Ucr); then the rats were sacrificed to collect carotid blood and to determine the levels of serum total protein (TP), albumin (Alb), globulin (Glo), total cholesterol (TC) and cytokine interlukin-4 (IL-4).

RESULTS

Six acidic components were isolated and identified from the PHE section: pachymic acid, 15α-hydroxydehydrotumulosic acid, trametenolic acid, dehydropachymic acid, 3β-hydroxy-lanosta-7,9(11), 24-trien-21-oic-acid and dehydroeburicoic acid. Compared with the model control group, the urine protein content were significantly decreased in the PHE treatment groups and positive control group (P<0.05), especially PHE middle-dose group (P<0.01). The Ucr values and serum levels of TP, Glo, TC and IL-4 in PHE low- and middle-dose groups were also presented obvious recover tendency as compared with the model control group (P<0.05 or P<0.01). However, positive control group and all PHE groups indicated no significant therapeutic effect on raising Alb value, although PHE low- and middle-dose treatment groups showed better outcomes than positive control group (P>0.05).

CONCLUSIONS

PHE showed an encouraging therapeutic effect against ADR-induced NS in a rat model. PHE might be a group of effective substances for the treatment of NS.

In vitro antioxidant and anti-inflammatory activities of extracts from Potentilla recta and its main ellagitannin, agrimoniin

ETHNOPHARMACOLOGICAL RELEVANCE

Potentilla recta is one of the numerous cinquefoil species growing in Poland. It is used in traditional medicine e.g. in the treatment of skin inflammation.

AIM OF THE STUDY

The purpose of the present study is to evaluate antioxidant and anti-inflammatory activities of extracts and subfractions of the P. recta herb (obtained by using solvents of different polarity) in in vitro systems as well as to examine their chemical composition.

MATERIALS AND METHODS

Antioxidant activities of the extracts, subfractions and agrimoniin were evaluated using DPPH and three other radicals (O2(-), H2O2, and HClO) generated in cell-free systems. Anti-hyaluronidase activity was measured by using the turbidimetric method. Inhibition of lipoxidase activity was measured spectrophotometrically, using linoleic acid as a substrate. The composition of the most active subfraction was determined using the HPLC-DAD-MS(n) method.

RESULTS

All tested samples showed scavenging activity against all the examined reactive species in a concentration-dependent manner. The highest scavenging activity against DPPH, H2O2 and HClO was observed in the ethyl acetate subfraction (PRE3) (SC50 ± SEM [μg/mL]: 25.39 ± 2.49, 1.79 ± 0.25 and 8.52 ± 1.16 respectively). It was only in the xanthine/xanthine oxidase system that the antioxidation potential of the diethyl ether subfraction (PRE2) (SC50 ± SEM [μg/mL]: 6.59 ± 1.33) was higher than that of the subfraction PRE3 (SC50 ± SEM [μg/mL]: 8.57 ± 1.37). Also, in the studies of lipoxidase and hyaluronidase inhibition activity the strongest effect was observed for PRE3, with IC50 [μg/mL] = 86.31 ± 5.46, and 12.99 ± 1.31, respectively. The chromatographic method (HPTLC-DPPH) revealed that the principal substance responsible for the activity, is a tannin like compound. Isolated agrimoniin showed significant reactive oxygen species scavenging activity and significant enzyme inhibition activity (including xanthine oxidase inhibition activity). Agrimoniin exerted the strongest scavenging activity against H2O2 (SC50 ± SEM [μM]: 0.20 ± 0.01). This compound also significantly inhibited the enzymatic activity of lipoxidase (IC50 [μM] = 36.47 ± 1.29), and, particularly, of hyaluronidase (IC50 [μM] = 2.65 ± 0.40).

CONCLUSIONS

The strong scavenging activity against H2O2, and the inhibition of the enzymatic activity of lipoxidase, and particularly, hyaluronidase observed for the tested subfractions and agrimoniin, partly explain the beneficial effects of P. recta in treatment of skin inflammation.