Citrus peel essential oils have an impressive range of food and medicinal uses. In the present study we investigated the variation in the yield and chemical composition of the essential oils isolated from fresh, ambient-, and oven-dried peels of three Citrus species namely Citrus reticulata (C. reticulata), Citrus sinensis (C. sinensis) and Citrus paradisii (C. paradisii). The hydro-distilled essential oil content from fresh-, ambient-, and oven-dried peels of C. reticulata, C. sinensis and C. paradisii ranged from 0.30-0.50, 0.24-1.07 and 0.20-0.40 g/100 g, respectively. The maximum amount of the oil was determined in oven-dried while the minimum in fresh peel samples. Using GC and GC/MS, a total of 16-27, 17-24 and 18-40 chemical constituents were identified in the peel essential oils of C. reticulate, C. sinensis and C. paradisii, respectively. The content of limonene, the most prevalent chemical constituent, detected in these essential oils, ranged from 64.1-71.1% (C. reticulata), 66.8-80.9% (C. sinensis) and 50.8-65.5% (C. paradisii). The yield and content of most of the chemical components including limonene (the principal chemical compound detected) of the tested essential oils varied significantly (p < 0.05) with respect to drying treatments and species employed.
This study was carried out to determine the effects of hydroxy propyl methyl cellulose (HPMC) on the flavour compounds
(eugenol and limonene), moisture and oil content in chicken nuggets during frying. Chicken nugget added with 500
ppm eugenol and limonene were coated with HPMC solution (0, 0.75 and 1.5%) and then with a commercial coating
(ADABI, Malaysia). Chicken nuggets were fried at 180o
C for 4 min. Quantity of eugenol and limonene in the substrate
(chicken meat) and coating were measured alongwith the moisture and oil content. The results showed that 0.75 and
1.5% HPMC were not able to retain either eugenol or limonene in both substrate and coating portion of the nuggets
when compared to control except for eugenol in the substrate portion when using 1.5% HPMC. Application of HPMC
also resulted in reduced moisture loss and oil absorption. The reduced moisture loss and oil absorption in the coating
and substrate of the chicken nuggets showed that HPMC was able to form a barrier that restricted the migration of
moisture from the nuggets and absorption of oil into the nuggets. However, only the 1.5% HPMC barrier formed was
able to reduce the loss of eugenol in the nugget substrate. Both 0.75 and 1.5% HPMC was not able to significantly
reduce the loss of limonene during frying.
DNA mismatch repair (MMR) deficiency has been associated with a higher risk of developing colorectal, endometrial, and ovarian cancer, and confers resistance in conventional chemotherapy. In addition to the lack of treatment options that work efficaciously on these MMR-deficient cancer patients, there is a great need to discover new drug leads for this purpose. In this study, we screened through a library of commercial and semisynthetic natural compounds to identify potential synthetic lethal drugs that may selectively target MLH1 mutants using MLH1 isogenic colorectal cancer cell lines and various cancer cell lines with known MLH1 status. We identified a novel diarylpentanoid analogue, 2-benzoyl-6-(2,3-dimethoxybenzylidene)-cyclohexenol, coded as AS13, that demonstrated selective toxicity toward MLH1-deficient cancer cells. Subsequent analysis suggested AS13 induced elevated levels of oxidative stress, resulting in DNA damage where only the proficient MLH1 cells were able to be repaired and hence escaping cellular death. While AS13 is modest in potency and selectivity, this discovery has the potential to lead to further drug development that may offer better treatment options for cancer patients with MLH1 deficiency.
Limonene oxidation products (LOPs) have gained interest on their harmful health effects over time. Recently, studies have shown that the selected LOPs: 4-oxopentanal (4-OPA), 3-isopropenyl-6-oxo-heptanal (IPOH) and 4-acetyl-1-methylcyclohexene (4-AMCH) have sensory irritation effects in mice and inflammatory effects in human lung cells. This study was therefore undertaken to investigate the potential capacity of 4-OPA, IPOH and 4-AMCH to cause cell membrane damage, oxidative stress and inflammation in human bronchial (16HBE14o-) and alveolar (A549) epithelial cell lines. Overall results suggest that 4-OPA, IPOH have cytotoxic effects on human lung cells that might be mediated by ROS: the highest concentration applied of IPOH [500 μM] enhanced ROS generation by 100-fold ± 7.7 (A549) and 230-fold ± 19.9 (16HBE14o-) compared to the baseline. 4-OPA [500 μM] increased ROS levels by 1.4-fold ± 0.3 (A549) and by 127-fold ± 10.5 (16HBE14o-), while treatment with 4-AMCH [500 μM] led to 0.9-fold ± 0.2 (A549) and 49-fold ± 12.8 (16HBE14o-) increase. IPOH [500 μM] caused a decrease in the thiol-state balance (e.g. after 2 h, GSH:GSSG was reduced by 37% compared to the untreated 16HBE14o-cells). 4-OPA [500 μM] decreased the GSH:GSSG by 1.3-fold change in A549 cells and 1.4-fold change in 16HBE14o-cells. No statistically significant decrease in the GSH:GSSG in A549 and 16HBE14o-cell lines was observed for 4-AMCH [500 μM]. In addition, IPOH and 4-OPA [31.2 μM] increased the amount of the inflammatory markers: RANTES, VEGF and EGF. On the other hand, 4-AMCH [31.2 μM] did not show inflammatory effects in A549 or 16HBE14o-cells. The 4-OPA, IPOH and 4-AMCH treatment concentration and time-dependently induce oxidative stress and/or alteration of inflammatory markers on human bronchial and alveolar cell lines.
Saffron, Crocus sativus (Iridaceae), is a perennial herb, which earned its popularity as both medicine and spice. It is an inhabitant of different mountainous regions of Asia Minor to Greece, Western Asia, Egypt, and India. The benefits of saffron as an antidepressant are well-documented. Almost 150 volatile and nonvolatile compounds are obtained from the chemical analysis of this plant. Fewer than 50 constituents elucidated and identified so far showed phytochemical characteristics. The major bioactive compounds identified are safranal, crocin, and picrocrocin, which are responsible for its aroma as well as its bitter taste. This review is an attempt to encompass the methods of analysis and pharmacodynamic and pharmacokinetic properties of saffron followed by its efficacious and safe potential.
Epilepsy is a neurological disorder characterized by recurrent seizures resulting from excessive abnormal electrical discharges in the brain. Medicinal plants may play an invaluable role to discover the new antiepileptic drugs. The aim of the present study was to investigate the anticonvulsant activity of α-terpineol isolated from Myristica fragrans Hountt. The α-terpineol showed a significant inhibition of the seizure episodes and spikes in absence seizures model of Genetic Absence Epilepsy Rats from Strasbourg (GAERS) rats by using electroencephalography records. It showed dose-dependent anticonvulsant activity that was comparable to the known antiepileptic drug of diazepam. It showed a rapid onset and relatively short duration of anticonvulsant effects. The present findings suggest that α-terpineol might possess antiepileptic activities against the partial seizures of human because it prevented seizures in well-established genetic absence seizure animal model of GAERS rats.
The essential oils obtained by hydrodistillation from the fresh leaf and stem of Piper porphyrophyllum N.E. Br. were analyzed by GC and GC/MS. Thirty four constituents were identified in the leaf oil, while thirty eight constituents were identified in the stems oil. The most abundant components in the leaf oil included bicyclogermacrene (14.7 %), α-copaene (13.2 %) and β-phellandrene (9.5 %) while sabinene (15.5 %), bicyclogermacrene (12.3 %) and α-copaene (8.1 %) were the main constituents in the stem oil. The evaluation of antibacterial activity by using micro-dilution method revealed that both oils were moderately active against all the Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (Pseudomonas aeruginosa, Pseudomonas putida and Escherichia coli) with minimum inhibitory concentration (MIC) values in the range 125-1000 µg/ml.
This study sets out to investigate the in vitro permeation of ketoprofen from the formulated nanoemulsions through excised rat skin. In vitro permeation of ketoprofen nanoemulsion through rat skin was evaluated in Franz diffusion cells and compared with marketed product (Fastum gel). Limonene which has been reported to be a good enhancer for ketoprofen was selected. Moreover the effects of limonene which was added to the nanoemulsion formulations at levels of 1%, 2%, 3% and on rat skin permeation of ketoprofen were also evaluated. The selected optimized formulation was further studied for skin irritation. Utilization of limonene as a penetration enhancer increased the permeation of ketoprofen from the formulated nanoemulsion with increasing concentrations of limonene. The results obtained showed that nanoemulsion with 3% limonene produced similar and comparable skin permeation of ketoprofen with marketed formulation and the skin irritation study on rats showed the optimized formulation prepared was safe.
Micro-emulsions and sometimes nano-emulsions are well known candidates to deliver drugs locally. However, the poor rheological properties are marginally affecting their acceptance pharmaceutically. This work aimed to modify the poor flow properties of a nano-scaled emulsion comprising palm olein esters as the oil phase and ibuprofen as the active ingredient for topical delivery. Three Carbopol ® resins: 934, 940 and Ultrez 10, were utilized in various concentrations to achieve these goals. Moreover, phosphate buffer and triethanolamine solutions pH 7.4 were used as neutralizing agents to assess their effects on the gel-forming and swelling properties of Carbopol ® 940. The addition of these polymers caused the produced nano-scaled emulsion to show a dramatic droplets enlargement of the dispersed globules, increased intrinsic viscosity, consistent zeta potential and transparent-to-opaque change in appearance. These changes were relatively influenced by the type and the concentration of the resin used. Carbopol ® 940 and triethanolamine appeared to be superior in achieving the proposed tasks compared to other materials. The higher the pH of triethanolamine solution, the stronger the flow-modifying properties of Carbopol ® 940. Transmission electron microscopy confirmed the formation of a well-arranged gel network of Carbopol ® 940, which was the major cause for all realized changes. Later in vitro permeation studies showed a significant decrease in the drug penetration, thus further modification using 10% w/w menthol or limonene as permeation promoters was performed. This resulted in in vitro and in vivo pharmacodynamics properties that are comparably higher than the reference chosen for this study.