This study of selected plants of the Rutaceae family was carried out to investigate their phenolic content, antioxidant activity, and the in vitro inhibitory potential of extracted phenolics towards enzymes relevant for hyperglycemia and hypertension. The phenolic content, antioxidant activity and phenolic extract-mediated inhibitory activities for α-glucosidase and α-amylase were evaluated by spectrophotometry. The content of individual phenolics and the angiotensin I-converting enzyme (ACE) inhibitory activity of the phenolic extracts were evaluated by LC/MS-MS and RP-HPLC methods, respectively. A higher percentage of free phenolic content was seen for all the selected plants of the Rutaceae family (85.43-92.82% of the total phenolic content) than of the bound form (7.18-14.57% of total phenolic content). The major predominant bound phenolic in lemon and red blood orange was hesperidin. The major predominant bound phenolic in pummelo, shamouti and clementine was ferulic acid. The highest ACE and α-glucosidase inhibitory activity of the extracted phenolics from lemon was associated with free phenolic extracts obtained at 30 °C with values of 100% inhibition. Red blood orange free phenolic extract (30 °C) elicited the highest α-amylase inhibition activity (32.3%). In contrast, extracted bound phenolics after acid and base hydrolysis from all selected plants from the Citrus species were shown to induce activation of the ACE and α-amylase enzymes.
The subtropical plant species Cyphostemma digitatum, Vitaceae, is used in central Yemen in traditional medicine, as a culinary herb, and as a source of food flavoring. The contents of vitamin C, vitamin E, and carotenoids and changes caused by common processing were investigated. Carotenoids were determined by reversed phase C30-high-performance liquid chromatography (HPLC) with diode array detection at 470 nm, while tocopherols and tocotrienols were analyzed by using normal phase HPLC with fluorescence detection (excitation, 292 nm; emission, 330 nm). Ascorbic acid was determined spectrophotometrically after reaction with DNP by measuring the absorbance at 520 nm. For the raw material and for the processed commercial food product, both in dried form, reasonable quantities of carotenoids were found in the raw material as follows: lutein, 18.89 +/- 0.73 mg/100 g; zeaxanthin, 9.46 +/- 0.30 mg/100 g; canthaxanthin, 0.21 +/- 0.01 mg/100 g; beta-cryptoxanthin, 0.67 +/- 0.03 mg/100 g; and beta-carotene, 14.60 +/- 0.46 mg/100 g. Household processing reduced the carotenoid contents dramatically; only beta-carotene sustained the processing. Likewise, vitamin C, 49.50 +/- 0.01 mg/100 g in the raw material and 20.30 +/- 0.02 mg/100 g in the processed material, was affected negatively by processing; only 41% was retained after processing. In contrast, the outstanding high content of vitamin E, 82.74 +/- 0.63 mg/100 g in the raw material, was increased by processing to 101.20 +/- 1.38 mg/100 g; it was found in different forms, some of which were rare in other sources.
Oleuropein, the main constituents of leaves and fruits of the olive tree, has been demonstrated to exert various therapeutic and pharmacological properties including antidiabetic effect. However, the effectiveness of oleuropein on glucose homeostasis in intact rat skeletal muscle ex vivo has never been explored. Therefore, our current study was carried out to investigate and confirm the beneficial effect of oleuropein (1.5 mM) on glucose uptake and on parameters relevant to the normal homeostatic mechanisms of glucose regulation in rat skeletal muscle. For this purpose, soleus muscles were incubated for 12 hr without (control) or with oleuropein, in the presence or absence of AMP-activated protein kinase (AMPK) inhibitor, compound C, or wortmannin, an inhibitor of phosphatidylinositol kinase. Oleuropein-stimulated glucose transport, plasmalemmal glucose transporter 4 (GLUT4), and phosphorylation of phosphatidylinositol kinase and AMPK were examined. We observed that oleuropein treatment enhanced glucose transport, GLUT4 translocation, and AMPK phosphorylation. The oleuropein-stimulated glucose uptake and GLUT4 translocation were inhibited by compound C and were not affected by wortmannin. These results suggest that increased glucose uptake induced by oleuropein might be mediated through activation of AMPK and the subsequent increase in GLUT4 translocation in skeletal muscles.
Large carnivores have extensive spatial requirements, with ranges that often span geopolitical borders. Consequently, management of transboundary populations is subject to several political jurisdictions, often with heterogeneity in conservation challenges. In continental Asia there are four threatened leopard subspecies with transboundary populations spanning 23 countries: the Persian Panthera pardus saxicolor, Indochinese P. pardus delacouri, Arabian P. pardus nimr and Amur P. pardus orientalis leopards. We reviewed the status of these subspecies and examined the challenges to, and opportunities for, their conservation. The Amur and Indochinese leopards have the majority (58–100%) of their remaining range in borderlands, and the Persian and Arabian leopards have 23–26% of their remaining ranges in borderlands. Overall, in 18 of 23 countries the majority of the remaining leopard range is in borderlands, and thus in most countries conservation of these subspecies is dependent on transboundary collaboration. However, we found only two transboundary initiatives for Asian leopards. Overall, we highlighted three key transboundary landscapes in regions that are of high importance for the survival of these subspecies. Recent listing of the leopard in the Bonn Convention on the Conservation of Migratory Species of Wild Animals is important, but more international collaboration is needed to conserve these subspecies. We provide a spatial framework with which range countries and international agencies could establish transboundary cooperation for conserving threatened leopards in Asia.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.