Antioxidant, Anti-Inflammatory and Attenuating Intracellular Reactive Oxygen Species Activities of Nicotiana tabacum var. Virginia Leaf Extract Phytosomes and Shape Memory Gel Formulation.

Oxidative stress is one of the major causes of skin aging. In this study, the shape memory gels containing phytosomes were developed as a delivery system for Nicotiana tabacum var. Virginia fresh (VFL) and dry (VDL) leaf extracts. The extracts were loaded in the phytosomes by a solvent displacement method. The physical and chemical characteristics and stability of phytosomes were evaluated by dynamic light scattering and phytochemistry, respectively. The in vitro antioxidant activity and intracellular reactive oxygen species reduction of phytosomes and/or extracts were investigated by the DPPH and ABTS radical scavenging assays, FRAP assay, and DCFH-DA fluorescent probe. The cytotoxicity and anti-inflammatory activity of VDL and VFL phytosomes were studied by an MTT and a nitric oxide assay, respectively. Here, we first reported the total phenolic content in the dry leaf extract of N. tabacum var. Virginia was significantly greater than that of the fresh leaf extract. The HPLC analysis results revealed that VDL and VFL extracts contained 4.94 ± 0.04 and 3.13 ± 0.01 µg/mL of chlorogenic acid and 0.89 ± 0.00 and 0.24 ± 0.00 µg/mL of rutin, respectively. The phytosomes of the VDL and VFL extracts displayed stable size, polydispersity index, zeta potential values, and good chemical stability. VDL and VDL phytosomes showed higher phenolic and flavonoid contents which showed stronger DPPH and ABTS radical scavenging effects and reduced the intracellular ROS. The results suggested that the phenolic compounds are the main factor in their antioxidant activity. Both VDL and VFL phytosomes inhibited nitric oxide production induced by LPS, suggesting the anti-inflammatory activity of the phytosomes. The shape memory gel containing VDL and VFL phytosomes had good physical stability in terms of pH and viscosity. The VDL and VFL phytosomes dispersed in the shape memory gels can be considered as a promising therapeutic delivery system for protecting the skin from oxidation and reactive oxygen species.

Phytochemical, Antioxidant, Antihyaluronidase, Antityrosinase, and Antimicrobial Properties of Nicotiana tabacum L. Leaf Extracts.

Nicotiana tabacum L. (tobacco) is an important and valuable crop for the cigarette industry. However, cigarette cessation has been encouraged worldwide. Therefore, this study aimed to investigate the potential of N. tabacum leaf extract use in other industries besides cigarette production, especially cosmeceutical industries, which are of interest for increasing the value and widening the applications of N. tabacum. The leaves of N. tabacum var. Virginia and Turkish were extracted by maceration using 95% v/v ethanol or petroleum ether. The extracts were evaluated for their phytochemical compositions, antioxidant capacity, and anti-aging, antimelanogenic, and antimicrobial activities. The phytochemical screening of the extracts revealed terpenoids, steroids, alkaloids, tannins, and carbohydrates in all of the N. tabacum leaf extracts. The total phenolic content was detected to be the highest in the ethanolic extract of Virginia tobacco leaf, which had the most significantly potent antioxidant and antihyaluronidase activity (P < 0.05). On the contrary, the extracts from the Turkish variety demonstrated the most powerful antimicrobial activity against Staphylococcus aureus. Thus, ethanolic extracts of N. tabacum var. Virginia are suggested as good natural anti-aging ingredients with potent antioxidant and antihyaluronidase effects, whereas the leaf of N. tabacum var. Turkish is suggested as a good source of natural antimicrobial components, particularly for S. aureus inhibition. In summary, in addition to the cigarette industry, N. tabacum leaf could be a source of pharmaceutical and cosmeceutical compounds, particularly natural anti-aging and antimicrobial ingredients.

Formulation and Characterization of Nicotine Microemulsion-Loaded Fast-Dissolving Films for Smoking Cessation.

The present study aimed to develop a nicotine microemulsion (NCT-ME) and incorporate it into a fast-dissolving film. The NCT-ME was prepared by mixing the specified proportions of nicotine (NCT), surfactant, co-solvent, and water. The NCT-ME was measured by its average droplet size, size distribution, zeta potential, and morphology. NCT-ME fast-dissolving films were prepared by the solvent casting technique. The films were characterized by morphology, weight, thickness, disintegration time, and mechanical strength properties and the determined NCT loading efficiency and in vitro drug release. The results showed that almost all NCT-MEs presented droplet sizes of less than 100 nm with a spherical form, narrow size distribution, and zeta potentials of -10.6 to -73.7 mV. There was no difference in weight and thickness between all NCT-ME films, but significant changes in the disintegration times were noticed in NCT40-Smix[PEG-40H(2:1)]10 film. The mechanical properties of films varied with changes in type of surfactant. About 80% of the drug release was observed to be between 3 and 30 min. The drug release kinetics were fitted with the Higuchi matrix model. The NCT40-Smix[P-80(1:1)]10 film showed the highest dissolution rate. It was concluded that the developed ME-loaded fast-dissolving film can increase drug release to a greater extent than the films without ME.

Elucidating Pathway and Anesthetic Mechanism of Action of Clove Oil Nanoformulations in Fish.

Clove oil (CO), an essential oil of Syzygium aromaticum, has been reported as an anesthetic for many fish species. However, its insoluble properties require a suitable delivery system for its application. In the present study, nanoformulations of CO as a nanoemulsion (CO-NE), a self-microemulsifying drug-delivery system (CO-SMEDDS), and a self-nanoemulsifying drug-delivery system (CO-SNEDDS) were prepared for delivering CO. Zebrafish were used as a fish model to investigate oil pathways. The result shows fluorescence spots of fluorescence-labeled CO accumulate on the gills, skin, and brain. All CO nanoformulations significantly increased penetration flux compared to CO ethanolic solution. Investigation of the anesthetic mechanism of action using a rat brain γ-aminobutyric acid subtype A (GABAA) receptor-binding test demonstrates that CO and its major compound, eugenol, modulate [3H]muscimol binding. CO-NE exhibited a concentration-dependent binding activity with an EC50 value of 175 µg/mL, significantly higher than CO solution in dimethyl sulfoxide. In conclusion, CO enters the fish through the skin and gills. The anesthetic mechanism of action of CO is based on modulation of [3H] muscimol binding to GABAA receptors. Among three nanoformulations tested, CO-NE is the most effective at increasing permeability and enhancing the receptor-binding activity of the oil.

Extraction of Nicotine from Tobacco Leaves and Development of Fast Dissolving Nicotine Extract Film.

Nicotine (NCT), administered in the form of a fast dissolving oral delivery system, can be a potential alternative to nicotine replacement therapy. NCT was extracted by maceration and acid-base extraction methods from Burley tobacco leaves with different stalk positions and extraction yield and NCT content were further determined. The extract with the highest nicotine content was selected for incorporation into a fast dissolving film formulation. The optimized film was evaluated for its physical and mechanical properties, in vitro disintegration, and drug release profile. The results demonstrated that the extract from the upper part of tobacco leaves using the acid-base extraction method had the highest amount of NCT. NCT fast dissolving film consisting of this extract as the active ingredient and HPMC E15 as a film polymer resulted in a homogeneous translucent film with a light brown color. The addition of NCT significantly affected the film properties in terms of weight, disintegration time, tensile strength, percentage elongation at break, and Young's modulus values. The drug release of NCT fast dissolving film showed a rapid initial release of 80% within three minutes, and its kinetics followed the Higuchi matrix model. The results suggest that these NCT films can be employed in the development of NCT fast dissolving films for clinical use.

Nanoemulsion: A suitable nanodelivery system of clove oil for anesthetizing Nile tilapia.

Clove oil ethanolic solution (CL-EtOH) have always been used for fish anesthesia. However, ethanol causes major side effect of fish hypersensivity. In this study, clove oil loaded nanoemulsion (CLN) was developed in order to enhance water miscibility of clove oil without using ethanol in the preparations. The obtained CLN was characterized in terms of droplet size, size distribution expressed as polydispersity index (PDI), and zeta potential. The anesthetic effect of CLN in comparison with CL-EtOH on Oreochromis niloticus (Nile tilapia) was investigated. The results showed that the best CLN was composed of 20% w/w clove oil and 15% w/w polysorbate 20. This CLN has internal droplet size of 63.2 ± 1.0 nm, PDI of 0.31 ± 0.04, and zeta potential of - 30.3 ± 8.1 mV. GC-MS analysis indicated that eugenol was the main compound in clove oil. It was found that the induction time to anesthesia for Nile tilapia that received this CLN was shorter than that received CL-EtOH at the same eugenol concentration. The results of this study showed the potential of nanoemulsion on water miscible and efficacy enhancing of clove oil without using ethanol. The obtained CLN from this study is a promising formulation for fish aquaculture where fish sedation is required.

Influence of clove oil and eugenol on muscle contraction of silkworm (Bombyx mori).

Clove oil is used in fish anesthesia and expected to have a mechanism via glutamic receptor. The present study explores the activities of clove oil and its major compound, eugenol, in comparison with L-glutamic acid on glutamic receptor of silkworm muscle and fish anesthesia. It was found that clove oil and eugenol had similar effects to L-glutamic acid on inhibition of silkworm muscle contraction after treated with D-glutamic acid and kainic acid. Anesthetic activity of the test samples was investigated in goldfish. The results demonstrated that L-glutamic acid at 20 and 40 mM could induce the fish to stage 3 of anesthesia that the fish exhibited total loss of equilibrium and muscle tone, whereas clove oil and eugenol at 60 ppm could induce the fish to stage 4 of anesthesia that the reflex activity of the fish was lost. These results suggest that clove oil and eugenol have similar functional activities and mechanism to L-glutamic acid on muscle contraction and fish anesthesia.

Anti-inflammatory Effects of Compounds from Polygonum odoratum.

Polygonum odoratum is an edible plant traditionally used as an antidiabetic, antimicrobial, anti-inflammatory, and antitumor agent in Asia. The aim of the study was to evaluate the anti-inflammatory effect of P. odoratum and the isolation and characterization of its main fractions. Extracts of the aerial parts were tested for anti-inflammatory activity as indicated by a change in the cytokine secretion in lipopolysaccharide-stimulated macrophages. After separation of the extract by reversed-phase high-performance liquid chromatography, the anti-inflammatory activity of the fractions was determined. Furthermore, the two main fractions were identified by nuclear magnetic resonance spectroscopy ((1)H- and (13)C-NMR). The ethanolic extract significantly reduced IL-6 secretion (IC50 25 pg/mL). The two main fractions (5 and 7) significantly decreased IL-6 production with an IC(50) of 102 µM (5) and 77 µM (7), respectively, and were identified as scutellarein-7-glucoside (5) and quercitrin (7). Since inflammation plays a major role in various diseases with high prevalence globally, it may be of importance that P. odoratum and its main constituents scutellarein-7-glucoside and quercitrin can be used as either an alternative or complementary treatment. Additionally, both are glycosides and their activity may be enhanced tremendously by deglycosylation by the gut microbiota.