The search for effective coronavirus disease (COVID-19) therapy has attracted a great deal of scientific interest due to its unprecedented health care system overload worldwide. We have carried out a study to investigate the in silico effects of the most abundant pomegranate peel extract constituents on the multi-step process of serious acute respiratory syndrome coronavirus 2 (SARS-CoV-2) internalization in the host cells. Binding affinities and interactions of ellagic acid, gallic acid, punicalagin and punicalin were studied on four selected protein targets with a significant and confirmed role in the process of the entry of virus into a host cell. The protein targets used in this study were: SARS-CoV-2 spike glycoprotein, angiotensin-converting enzyme 2, furin and transmembrane serine protease 2. The results showed that the constituents of pomegranate peel extracts, namely punicalagin and punicalin had very promising potential for significant interactions with the selected protein targets and were therefore deemed good candidates for further in vitro and in vivo evaluation.

Background: Type 2 diabetes mellitus (T2DM) is commonly associated with hyperglycemia, dyslipidemia, oxidative stress and inflammation which are well known cardiovascular risk factors. Pomegranate peel polyphenols have a proven hypolipemic, antioxidant and anti-inflammatory activity. However, there is a lack of clinical studies that would confirm its antioxidant and anti-inflammatory effects in diabetic patients. The potential of pomegranate peel extract (PoPEx) to counteract inflammation and oxidative stress in T2DM patients was investigated. For this purpose, a randomized, double-blind placebo-controlled study involving adult T2DM patients treated with PoPEx or placebo for eight-weeks was conducted. Methods: Patients were randomly divided into two groups: the first group (n = 30) received capsules containing PoPEx 250 mg twice daily, while the placebo group (n = 30) received placebo capsules twice daily. Plasma concentration of inflammatory factors (interleukin 6 (IL-6), tumor necrosis factor α (TNF-α) and high sensitivity C reactive protein (hsCRP)), oxidative stress biomarkers (thiobarbituric acid reactive substances (TBARS), nitrites (NO2 − ), superoxide anion radical (O2 − ), hydrogen peroxide (H2O2), total antioxidant capacity (TAC)), homocysteine and lipid profile were analyzed. Results: The PoPEx treatment showed a significant reduction of inflammatory factors (IL-6, TNF-α, hsCRP), oxidative stress biomarkers (TBARS, NO2 − , O2 − ) and homocysteine, while the TAC was increased. Moreover, a significant improvement in lipid profile was observed in the PoPEx group. Additional analysis showed a significant inverse correlation between the decrements of all measured inflammatory markers and TAC in the PoPEx group. Conclusions: The study demonstrated that eight-week-long PoPEx administration had favorable effects on inflammatory status and oxidative stress biomarkers in diabetic patients.

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The chemical composition of the essential oils of Seseli gracile Waldst. & Kit. from natural habitat (Đerdap Gorge, Serbia) and from cultivated plants (Belgrade, Serbia) were characterized. The essential oils of the root, aerial parts, inflorescence and fruit were analyzed by GC/MS and GC/FID. Monoterpene hydrocarbons were the main compounds in the essential oil of aerial parts (45.2-93.0 %), inflorescences (84.1 and 90.0 %) and fruit (85.0 %). Polyacetylenes (38.8 and 87.6 %) were dominant in the essential oil of root. The cluster analysis revealed that there were significant differences in the chemical composition of the S. gracile oils at different phenological stages. On the other hand, essential oils from the aerial parts from natural and cultivated plants showed quite uniform qualitative composition. The aerial parts essential oil from natural habitat contained higher content of para-cymene (mean values 17.3 vs. 6.5 %) and lower amounts of terpinolene (mean values 23.1 vs. 49.9 %). Also polyacetylene falcarinol was present only in the aerial parts samples from natural habitat. The essential oil of inflorescences from natural habitat contained higher concentration of terpinolene, quite similar amount of para-cymene and lower content of α-pinene.

The present paper describes environmental and seasonal-related chemical composition variations, vasorelaxant and angiotensin I-converting enzyme (ACE) activities of essential oil from aerial parts of Seseli pallasii BESSER. The composition was analyzed by GC and GC/MS. Monoterpenes were found to be the most abundant chemical class with a-pinene (42.7 -48.2%) as the most prevalent component. Seseli pallasi essential oil relaxed isolated endothelium-intact mesenteric arteries rings precontracted with phenylephrine with IC 50 = 3.10 nl/ml (IC 50 = 2.70 lg/ ml). Also, S. pallasii essential oil was found to exhibit a dose-dependent ACE inhibitory activity with an IC 50 value of 0.33 mg/ml. In silico evaluation of ACE inhibitory activity of the individual components showed that spathulenol exhibited the best binding affinity with ACE, and the lowest binding energy of À7.5 kcal/mol. The results suggested that combination of vasorelaxing and ACE inhibitory effects of the analyzed S. pallasii essential oil might have the potential therapeutic significance in hypertension.

Background/Aim: Due to the numerous beneficial effects of pomegranate that can be explained through its antioxidative effects, the aim of this study was to determine the antioxidant potential of pomegranate peel extract (PoPEx) prepared from pomegranate that was harvested in the southeast region of Herze-govina (Bosnia and Herzegovina), through in vitro and in vivo studies. Methods: In PoPEx total phenols, flavonoids, flavonols, flavan-3-ols and antho-cyanins content was determined, as well as several antioxidative assays, including 2,2 diphenyl-1-picrylhydrazyl assay (DPPH), 2,2'-azino bis(3-ethylbenzothi-azoline-6-sulphonic acid) assay (ABTS), iron (III)-2,4,6-tripyridyl-S-triazine complex assay (FRAP), reduction of copper(II) ions (CUPRAC) assay, Briggs-Rauscher oscillatory reactions, neutralisation of OH radicals and lipid peroxidation assay. In vivo studies were performed by administrating 100 mg/ kg of body weight of PoPEx to the rats by gavage for 7 days, after which the rats were euthanised and prooxidative parameters (thiobabrituric acid reactive substances-TBARS as an index of lipid peroxidation, nitrites-NO 2 , hydrogen peroxide-H 2 O 2 and superoxide anion radical O 2-) were determined in plasma, as well as antioxidative parameters (superoxide dismutase-SOD, reduced gluta-thione-GSH and catalase-CAT) in erythrocyte lysates. Results: High content of phenolic compounds was found in PoPEx, which resulted in high antioxidative potential in all in vitro tests performed. In vivo study showed that PoPEx administration caused a significant decrease in TBARS, NO 2-, as well as an increase in reduced glutathione (p < 0.05) in comparison to the control group, while H 2 O 2 and O 2 * showed a lowering trend and SOD and CAT showed an increasing trend in PoPEx group, but without statistical significance. Conclusion: PoPEx demonstrated high antioxidative capacity measured in vitro and in vivo and can be potentially used as a supplement treatment in the prevention of various inflammatory conditions.

Since the outbreak of the COVID-19 pandemic, it has been obvious that virus infection poses a serious threat to human health on a global scale. Certain plants, particularly those rich in polyphenols, have been found to be effective antiviral agents. The effectiveness of Alchemilla viridiflora Rothm. (Rosaceae) methanol extract to prevent contact between virus spike (S)-glycoprotein and angiotensin-converting enzyme 2 (ACE2) and neuropilin-1 (NRP1) receptors was investigated. In vitro results revealed that the tested samples inhibited 50% of virus-receptor binding interactions in doses of 0.18 and 0.22 mg/mL for NRP1 and ACE2, respectively. Molecular docking studies revealed that the compounds from A. viridiflora ellagitannins class had a higher affinity for binding with S-glycoprotein whilst flavonoid compounds more significantly interacted with the NRP1 receptor. Quercetin 3-(6”-ferulylglucoside) and pentagalloylglucose were two compounds with the highest exhibited interfering potential for selected target receptors, with binding energies of −8.035 (S-glycoprotein) and −7.685 kcal/mol (NRP1), respectively. Furthermore, computational studies on other SARS-CoV-2 strains resulting from mutations in the original wild strain (V483A, N501Y-K417N-E484K, N501Y, N439K, L452R-T478K, K417N, G476S, F456L, E484K) revealed that virus internalization activity was maintained, but with different single compound contributions.