Investigation of Enzyme Inhibitory Activities, Antioxidant Activities, and Chemical Properties of Pistacia vera Leaves Using LC-QTOF-MS and RP-HPLC.

Since the leaves of some Pistacia species are used in traditional folk medicine for diabetes, this study investigated the in vitro antidiabetic effect (α-glucosidase and α-amylase) of Pistacia vera leaves. Additionally, the current study investigated the antihypercholesterolemic (cholesterol esterase), antiobesity (pancreatic lipase), and antioxidant activities (i.e., total antioxidant capacity, DPPH (2,2-Diphenyl-1-picrylhydrazyl) radical scavenging activity, metal chelating activity, and ferric-reducing antioxidant power) of P. vera leaves. The aqueous-alcoholic leaf extract inhibited α-amylase, α-glucosidase, and pancreatic lipase with the half-maximal inhibitory concentration values of 7.74 ± 0.72, 11.08 ± 3.96, and 168.43 ± 26.10 µg/mL, respectively. It was determined that the crude extract had high DPPH radical scavenging activity, ferric-reducing power, and moderate metal chelating activity. The ethyl acetate (EtOAc) subextract obtained by the liquid-liquid fractionation of the crude extract showed potent α-amylase and α-glucosidase inhibitory activities. The EtOAc subextract (5.794 ± 0.027 g/100 g subextract) was standardized by reversed-phase high-performance liquid chromatography based on ß-pentagalloyl glucose, which showed inhibitory effects on both amylase and glucosidase enzymes. Fifteen compounds, seven of which are organic acid derivatives and eight of which are flavonoids, were identified by liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) analysis in the crude extract of P. vera leaves. Seven of the fifteen phenolic compounds detected in the crude extract by LC-QTOF-MS have both glucosidase and amylase inhibitory effects. As a result, P. vera leaves can be a potential source for compounds with high antioxidant effects that show inhibitory effects on enzymes involved in carbohydrate digestion in the prevention and treatment of diabetes or can be evaluated as a standardized extract.

Profiling the annual change of the neurobiological and antioxidant effects of five Origanum species in correlation with their phytochemical composition.

The ethanol extracts of five Origanum species: O. majorana L., O. onites L., O. syriacum L., O. vulgare subsp. hirtum (Link) Ietsw., and O. vulgare subsp. viride (Boiss.) Hayek, collected annually (each month), were investigated for their cholinesterase inhibition and antioxidant effects. The phytochemical composition of a total of 60 extracts was assessed by HPLC-DAD-ESI/HRMS, revealing the presence of a total of 73 compounds. Possible correlation between the bioactivity and metabolite profiles during 12 months was monitored. Acetylcholinesterase (AChE) inhibitory activity was found to be the highest between April and November (50.29-75.95%, 200 µg/mL), while the highest inhibition towards butyrylcholinesterase (BChE) was observed for the extracts between April and October (71.68-88.97%). Aromadendrin showed good correlation with anti-AChE, anti-BChE and reducing power activities. Furthermore, molecular docking data with aromadendrin, caffeoylarbutin and eriodictyol indicated that caffeoylarbutin had the lowest binding energy against both enzymes.

Theophylline attenuates bleomycin-induced oxidative stress in rats: The role of IL-6, NF-κB, and antioxidant enzymes

Abstract The purpose of this study was to evaluate the antifibrotic and antioxidant roles of theophylline (Theo), a bioactive compound, in bleomycin (BLM)-induced pulmonary fibrosis in Wistar albino rats. Assigned into 4 groups were 32 Wistar albino rats, comprising the control group (administered 0.9% isotonic saline), BLM group (treated with BLM at a dose of 2.5 mg/kg), BLM+Theo group (treated with Theo at a dose of 75 mg/kg + BLM at a dose of 2.5 mg/kg), and Theo group (treated with Theo at a dose of 75 mg/kg). In the BLM group, a significant decrease was observed in the catalase and glutathione peroxidase enzyme activities, and reduced glutathione (GSH) (p < 0.05, p< 0.05, p< 0.001, respectively), while the malondialdehyde (MDA) levels (p< 0.001) were significantly elevated when compared to the control group. However, the MDA levels in the BLM+Theo group were also significantly higher than in the control group (p< 0.01). Similarly, the GSH levels were significantly higher in the BLM+Theo group than in the BLM group (p< 0.05). The results indicated that Theo reduced the BLM-induced activation of nuclear factor-kappaB (NF-κB) and decreased interleukin-6 (IL-6) levels, together with significant amelioration of the immunohistochemical and histopathological architecture in the lung tissues. It was concluded that the administration of Theo had a positive effect on the GSH level, and activation of NF-κB and IL-6 expression, which were significant proinflammatory markers in the BLM-treated rats.

Standardization of Juniperus macrocarpa Sibt. & Sm. and Juniperus excelsa M. Bieb. Extracts with Carbohydrate Digestive Enzyme Inhibitory and Antioxidant Activities.

Juniperus species growing in Turkey are used for various medicinal purposes in traditional folk medicine. We aimed to evaluate in-vitro antidiabetic (α-glucosidase and α-amylase inhibition assays), antiobesity (pancreatic lipase inhibition assay), and antioxidant (ABTS and DPPH radical scavenging activities, ferric reducing activity, metal chelating activity, and phosphomolybdenum assay) activities of the extracts obtained from branches, leaves, and fruits of Juniperus macrocarpa and Juniperus excelsa. The branch (IC50 = 67.1 ± 1.7 µg/mL) and leaf ethyl acetate extracts (IC50 = 83.4 ± 0.8 µg/mL) of J. macrocarpa exhibited the strongest activity on the α-glucosidase enzyme. Besides that, J. excelsa leaf methanol extract exerted remarkable α-amylase inhibitory activity (IC50 = 950.1 ± 3.5 µg/mL). Only J. macrocarpa branch and J. excelsa leaf ethyl acetate extract slightly inhibited pancreatic lipase enzyme with 2963.3 ± 736.4 and 2343 ± 557.8 µg/mL IC50 values, respectively. The RP-HPLC-DAD analysis results demonstrated that the more active J. macrocarpa extracts are richer in agathisflavone, amentoflavone, and umbelliferone than J. excelsa extracts. With this study, it is concluded that J. macrocarpa branch and leaf ethyl acetate extracts may be a new source of α-glucosidase enzyme inhibitory activity and agathisflavone, amentoflavone can be used in the standardization of the extracts.

Preclinical Study on the Hepatoprotective Effect of Pollen Extract of Pinus brutia Ten. (Red Pine) in Mice and Phenolic Acid Analysis

Objectives: Many agents, including those from herbal sources, have been sought as preventives or cures for hepatotoxicity. The pollen of Pinus brutia Ten., known as red pine (Pinaceae), is used against liver diseases in Anatolian folk medicine. Materials and Methods: In the current study, pollen ethanol extract of P. brutia was investigated for its possible hepatoprotective activity using a mouse model of CCl4-induced hepatotoxicity. Swiss albino mice were divided into five groups, and extract-treated groups were compared with a silymarin-treated group as the reference. The extract was tested at 100, 200, and 300 mg/kg (b.w.). Phenolic acids were analyzed using high-performance column chromatography (HPLC) in the extracts as pollens are usually known to be rich in phenolics. Results: Our data revealed that the extract displayed the best hepatoprotection at a dose of 100 mg/kg when compared with silymarin (Legalon®), the reference drug. HPLC analysis indicated presence of protocatechuic acid (0.176 mg/g extract), p-hydroxybenzoic acid (0.001 mg/g extract), vanillic acid (VA) (0.537 mg/g extract), syringic acid (0.050 mg/g extract), and tr-cinnamic acid (0.310 mg/g extract), while the major phenolic acid was VA. Conclusion: The outcomes of this study allow us to conclude that red pine pollen extract can serve as a promising hepatoprotective agent. Among the phenolic acids analyzed in the pollen extract, vanillic acid as the major one besides some other phenolic acids detected seems to be responsible for its remarkable hepatoprotective effect.

Activity-guided isolation of α-amylase, α-glucosidase, and pancreatic lipase inhibitory compounds from Rhus coriaria L.

The leaves and fruits of Rhus coriaria are traditionally used in Turkey for the treatment of diabetes. The aim of the present study is to determine α-amylase, α-glucosidase, and pancreatic lipase inhibitory activities of R. coriaria leaf and fruit ethanol extracts (80%), and to isolate active compounds against these enzymes. As a result of the activity-guided isolation, the active compounds were determined as the amentoflavone, agathisflavone, and 1,2,3,4,6-penta-O-galloyl-ß-glucopyranose. Agathisflavone, amentoflavone, and penta-O-galloyl-ß-glucopyranose inhibited α-glucosidase with 11.4 ± 0.9, 11.3 ± 0.7, and 4.1 ± 0.1 µM IC50 values, respectively. Furthermore, penta-O-galloyl-ß-glucopyranose inhibited α-amylase with 6.32 ± 0.18 µM IC50 . These three compounds also significantly inhibited (P < 0.05) pancreatic lipase. The results of high-performance liquid chromatography analysis showed that penta-O-galloyl-ß-D-glycopyranose was one of the main compounds in both fruit and leaf extracts. Therefore, it may be considered that R. coriaria fruit and leaf extracts can be standardized on this substance and used in the development of both medicinal products and functional food for diabetes. PRACTICAL APPLICATION: Rhus coriaria (Sumac) is one of the plants that is well known and used around the world as a spice. It is also used against diabetes traditionally. The determination of effective compounds can lead to the standardization and development of both medicinal products and functional foods for diabetes. While the fruits of the plant are used as a spice all around the world, the leaves are generally throw away; therefore, the usage of the leaves to the food and medical industry can lead to beneficial effects on the economy.