Gunes Ak

Mrs. Gunes Ak


Research Focus & Metrics

Academic Career Length

8Years (2019-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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19 April 2021 in Pharmaceuticals
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Tapan BehlTapan Behl
Tapan Behl
Gabriele RocchettiGabriele Rocchetti
Gabriele Rocchetti
SCSwati Chadha
Swati Chadha
Gökhan ZenginGökhan Zengin
Gökhan Zengin
Simona BungăuSimona Bungău
Simona Bungău
Domenico MontesanoDomenico Montesano
Domenico Montesano
To date, the leading causes of mortality and morbidity worldwide include viral infections, such as Ebola, influenza virus, acquired immunodeficiency syndrome (AIDS), severe acute respiratory syndrome (SARS) and recently COVID-19 disease, caused by the SARS-CoV-2 virus. Currently, we can count on a narrow range of antiviral drugs, especially older generation ones like ribavirin and interferon which are effective against viruses in vitro but can often be ineffective in patients. In addition to these, we have antiviral agents for the treatment of herpes virus, influenza virus, HIV and hepatitis virus. Recently, drugs used in the past especially against ebolavirus, such as remdesivir and favipiravir, have been considered for the treatment of COVID-19 disease. However, even if these drugs represent important tools against viral diseases, they are certainly not sufficient to defend us from the multitude of viruses present in the environment. This represents a huge problem, especially considering the unprecedented global threat due to the advancement of COVID-19, which represents a potential risk to the health and life of millions of people. The demand, therefore, for new and effective antiviral drugs is very high. This review focuses on three fundamental points: (1) presents the main threats to human health, reviewing the most widespread viral diseases in the world, thus describing the scenario caused by the disease in question each time and evaluating the specific therapeutic remedies currently available. (2) It comprehensively describes main phytochemical classes, in particular from plant foods, with proven antiviral activities, the viruses potentially treated with the described phytochemicals. (3) Consideration of the various applications of drug delivery systems in order to improve the bioavailability of these compounds or extracts. A PRISMA flow diagram was used for the inclusion of the works. Taking into consideration the recent dramatic events caused by COVID-19 pandemic, the cry of alarm that denounces critical need for new antiviral drugs is extremely strong. For these reasons, a continuous systematic exploration of plant foods and their phytochemicals is necessary for the development of new antiviral agents capable of saving lives and improving their well-being.

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Viviana di GiacomoViviana di Giacomo
Viviana di Giacomo
Annalisa ChiavaroliAnnalisa Chiavaroli
Annalisa Chiavaroli
Lucia RecinellaLucia Recinella
Lucia Recinella
Giustino OrlandoGiustino Orlando
Giustino Orlando
Amelia CataldiAmelia Cataldi
Amelia Cataldi
Claudio FerranteClaudio Ferrante
Claudio Ferrante
Cannabidiol (CBD) and cannabigerol (CBG) are Cannabis sativa terpenophenols. Although CBD’s effectiveness against neurological diseases has already been demonstrated, nothing is known about CBG. Therefore, a comparison of the effects of these compounds was performed in two experimental models mimicking the oxidative stress and neurotoxicity occurring in neurological diseases. Rat astrocytes were exposed to hydrogen peroxide and cell viability, reactive oxygen species production and apoptosis occurrence were investigated. Cortexes were exposed to K+ 60 mM depolarizing stimulus and serotonin (5-HT) turnover, 3-hydroxykinurenine and kynurenic acid levels were measured. A proteomic analysis and bioinformatics and docking studies were performed. Both compounds exerted antioxidant effects in astrocytes and restored the cortex level of 5-HT depleted by neurotoxic stimuli, whereas sole CBD restored the basal levels of 3-hydroxykinurenine and kynurenic acid. CBG was less effective than CBD in restoring the levels of proteins involved in neurotransmitter exocytosis. Docking analyses predicted the inhibitory effects of these compounds towards the neurokinin B receptor. Conclusion: The results in the in vitro system suggest brain non-neuronal cells as a target in the treatment of oxidative conditions, whereas findings in the ex vivo system and docking analyses imply the potential roles of CBD and CBG as neuroprotective agents.

27 October 2021 in Antioxidants
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Adriano MollicaAdriano Mollica
Adriano Mollica
GSGiuseppe Scioli
Giuseppe Scioli
AVAlice Della Valle
Alice Della Valle
ACAngelo Cichelli
Angelo Cichelli
ENEttore Novellino
Ettore Novellino
Azzurra StefanucciAzzurra Stefanucci
Azzurra Stefanucci
Grape pomace is commonly considered a waste product of monovarietal red wine production. Methods: HPLC-DAD analysis was performed to determine the polyphenol and flavonoid contents of all the extracts obtained from Montepulciano d’Abruzzo red wine and grape skins whereas, GC-MS was applied to the determination of fatty acid composition in grape seeds oil. Biological characterization involves antioxidant and antimicrobial assays for all the extracts and seeds oil; Their ability to inhibit α-glucosidase, α-amylase, α-tyrosinase, and ChE enzymes was also detected, together with anti-inflammatory activity on wine, grape skin extracts, and seeds oil by lipoxygenase (5-LOX) and LPS-stimulated macrophage release assays. Data indicate significative polyphenols content (199.31 ± 7.21 mgGAE/g), antioxidant (CUPRAC assay (1036.98 mgTE/g)), enzymatic inhibition (α-tyrosinase: 151.30 ± 1.20 mgKAE/g) and anti-inflammatory activities for wine-organic extract 2, while the antimicrobial activity of grape skin decoction is higher than those reported by wine extracts on three bacterial strains. Interestingly only dealcoholized wine and wine-aqueous extract exerts inhibitory effects on α-glucosidase (20.62 ± 0.23 mmolACAE/g and 19.81 ± 0.03 mmolACAE/g, respectively), while seeds oil is rich in oleic and linoleic acids. These results confirm the strong antioxidant properties of Montepulciano d’Abruzzo grape pomace, suggesting the potential use of this waste product as functional food supplements in the human diet and in cosmeceutics.

26 August 2020 in Applied Sciences
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GAGunes Ak
Gunes Ak
Gökhan ZenginGökhan Zengin
Gökhan Zengin
SISinan Kouadio Ibrahime
Sinan Kouadio Ibrahime
FMFawzi Mohamad Mahomoodally
Fawzi Mohamad Mahomoodally
CPCarene Picot
Carene Picot
Domenico MontesanoDomenico Montesano
Domenico Montesano
Calendula officinalis L., (marigold), well known for its medicinal properties, has been extensively studied for its therapeutic properties. Nonetheless, as far as the literature could establish, no study has attempted to comparatively assess the biological (antioxidant and enzyme inhibitory potential) of the flowers, leaves, and roots of C. officinalis extracted using conventional (maceration and Soxhlet extraction (SE)) and non-conventional extraction (homogenizer (HAE) and ultrasound (UAE) assisted extraction) techniques. The detailed phytochemical profile of each extract along with the concentration of specific bioactive compounds has also been established. Total phenolic content was highest for the flower extracts while flavonoid content was highest in the leaf extracts. Phytochemical profiling showed that the extraction method influenced the phytochemical composition of the extract. Nicotiflorin was identified in the flower extracts only while amentoflavone occurred only in the roots, inferring that the occurrence of bioactive compounds varies within a plant. The flower extracts showed highest antioxidant potential while the roots extracts were potent inhibitors of cholinesterase and tyrosinase. This study provides valuable data on the influence of extraction techniques on the recovery of bioactive compounds from plants. In an endeavor to scale-up extraction from plant considering the more efficient extraction method is of paramount importance. Moreover, the study highlighted the necessity to thoroughly examine the biological activities of various parts of a plant obtained via different extraction protocols.

30 August 2022 in Molecules
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HOHaifa A. A. Omer
Haifa A. A. Omer
Giovanni CaprioliGiovanni Caprioli
Giovanni Caprioli
Doaa AboueleneinDoaa Abouelenein
Doaa Abouelenein
Ahmed MustafaAhmed Mustafa
Ahmed Mustafa
AUAbdullahi Ibrahim Uba
Abdullahi Ibrahim Uba
Sakina YagiSakina Yagi
Sakina Yagi
Several species within the genera Cassia or Senna have a treasure of traditional medicines worldwide and can be a promising source of bioactive molecules. The objective of the present study was to evaluate the phenolic content and antioxidant and enzyme inhibition activities of leaf methanolic extracts of C. fistula L., C. grandis L., S. alexandrina Mill., and S. italica Mill. The two Cassia spp. contained higher total polyphenolic content (42.23–49.75 mg GAE/g) than the two Senna spp., and C. fistula had significantly (p ˂ 0.05) the highest concentration. On the other hand, the Senna spp. showed higher total flavonoid content (41.47–59.24 mg rutin equivalent per g of extract) than that found in the two Cassia spp., and S. alexandrina significantly (p ˂ 0.05) accumulated the highest amount. HPLC–MS/MS analysis of 38 selected bioactive compounds showed that the majority of compounds were identified in the four species, but with sharp variations in their concentrations. C. fistula was dominated by epicatechin (8928.75 µg/g), C. grandis by kaempferol-3-glucoside (47,360.04 µg/g), while rutin was the major compound in S. italica (17,285.02 µg/g) and S. alexandrina (6381.85). The methanolic extracts of the two Cassia species exerted significantly (p ˂ 0.05) higher antiradical activity, metal reducing capacity, and total antioxidant activity than that recorded from the two Senna species’ methanolic extracts, and C. fistula displayed significantly (p ˂ 0.05) the highest values. C. grandis significantly (p ˂ 0.05) exhibited the highest metal chelating power. The results of the enzyme inhibition activity showed that the four species possessed anti-AChE activity, and the highest value, but not significantly (p ≥ 0.05) different from those obtained by the two Cassia spp., was exerted by S. alexandrina. The Cassia spp. exhibited significantly (p ˂ 0.05) higher anti-BChE and anti-Tyr properties than the Senna spp., and C. grandise revealed significantly (p ˂ 0.05) the highest values. C. grandise revealed significantly (p ˂ 0.05) the highest α- amylase inhibition, while the four species had more or less the same effect against the α-glucosidase enzyme. Multivariate analysis and in silico studies showed that many of the identified phenols may play key roles as antioxidant and enzyme inhibitory properties. Thus, these Cassia and Senna species could be a promising source of natural bioactive agents with beneficial effects for human health.

6 November 2020 in Antibiotics
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Journal Article
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Claudio FerranteClaudio Ferrante
Claudio Ferrante
Annalisa ChiavaroliAnnalisa Chiavaroli
Annalisa Chiavaroli
Paola AngeliniPaola Angelini
Paola Angelini
RVRoberto Venanzoni
Roberto Venanzoni
Giancarlo Angeles FloresGiancarlo Angeles Flores
Giancarlo Angeles Flores
Giustino OrlandoGiustino Orlando
Giustino Orlando
Prostatitis is an inflammatory condition that is related to multiple infectious agents, including bacteria and fungi. Traditional herbal extracts proved efficacious in controlling clinical symptoms associated with prostatitis. In this context, the aim of the present study was to explore the efficacy of extracts from Solidago virga-aurea, Ononis spinosa, Peumus boldus, Epilobium angustifolium, and Phyllanthus niruri against bacterial (Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus) and fungi strains (Candida albicans; C. tropicalis) involved in prostatitis. Additionally, anti-mycotic effects were tested against multiple species of dermatophytes (Trichophyton rubrum, T. tonsurans, T. erinacei, Arthroderma crocatum, A. quadrifidum, A. gypseum, A. currey, and A. insingulare). Antioxidant effects were also evaluated in isolated rat prostates challenged with lipopolysaccharide (LPS), and phytochemical analyses were conducted to identify and quantify selected phenolic compounds, in the extracts. Finally, a bioinformatics analysis was conducted to predict putative human and microbial enzymes targeted by extracts’ phytocompounds and underlying the observed bio-pharmacological effects. The phytochemical analysis highlighted that rutin levels could be crucial for explaining the highest antibacterial activity of P. boldus extract, especially against E. coli and B. cereus. On the other hand, in the E. angustifolium extract, catechin concentration could partially explain the highest efficacy of this extract in reducing lipid peroxidation, in isolated rat prostates stimulated with LPS. Concluding, the results of the present study showed moderate antimicrobial and anti-inflammatory effects induced by water extracts of S. virga-aurea, P. boldus, E. angustifolium, P. niruri, and O. spinosa that could be related, at least partially, to the phenolic composition of the phytocomplex.