Parkinson's disease (PD) is a neurodegenerative movement disorder due to selective loss of dopaminergic neurons of mesencephalic substantia nigra pars compacta (SNC) with debilitating motor symptoms. Current treatments for PD afford symptomatic relief with no prevention of disease progression. Due to the antioxidant and neuroprotective potential of sinapic acid, this study was conducted to evaluate whether this agent could be of benefit in an experimental model of early PD in rat. Unilateral intrastriatal 6-hydroxydopamine (6-OHDA)-lesioned rats were pretreated p.o. with sinapic acid at doses of 10 or 20 mg/kg. One week after surgery, apomorphine caused significant contralateral rotations, a significant reduction in the number of Nissl-stained and tyrosine hydroxylase (TH)-positive neurons and a significant increase of iron reactivity on the left side of SNC. Meanwhile, malondialdehyde (MDA) and nitrite levels in midbrain homogenate significantly increased and activity of superoxide dismutase (SOD) significantly reduced in the 6-OHDA-lesioned group. In addition, sinapic acid at a dose of 20 mg/kg significantly improved turning behavior, prevented loss of SNC dopaminergic neurons, lowered iron reactivity, and attenuated level of MDA and nitrite. These results indicate the neuroprotective potential of sinapic acid against 6-OHDA neurotoxicity that is partially due to the attenuation of oxidative stress and possibly lowering nigral iron level.

La 1-x Zr x NiO 3 perovskite nanocatalysts were synthesized by citrate sol-gel method. The synthesized samples were characterized by using X-ray diffraction (XRD), temperature programmed reduction (TPR), and inductively coupled plasma (ICP) techniques. Surface areas of the compounds were measured by BET method. Morphology study of the nanocatalysts was performed using scanning electron microscopy. The XRD patterns confirmed a well-crystallized structure in doping level up to 0.2 for La 1-x Zr x NiO 3 . The SEM images showed that the synthesized particles were in nanoscale. The TPR analysis revealed that by increasing the amount of Zr in the prepared samples, reduction process became difficult. The catalytic activity of the nanocatalysts was studied in dry reforming of methane (DRM) with CO 2 and the H 2 /CO ratio~1 when doping level was 0.1.

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The estreification of chrysin with α‐Linolenic acid (complex I) and linoleic acid (complex II) poly unsaturated fatty acids resulted to design of new mushroom tyrosinase (MT) inhibitors. Thermodynamic parameters of enzymes, including the melting point (Tm) and ∆G values, were obtained from thermal and chemical denaturation curves. Complexes I and II showed a competitive inhibitory effect on MT with Ki values of 0.45 and 0.29 mM, respectively. The Tm values were calculated as 328.6, 322.4, and 318 K and the ∆G values as 62.8, 52.9, and 47.1 KJ mol−1 for the enzyme alone and its interaction with complexes I and II, respectively. Intrinsic and extrinsic fluorescence techniques showed structural instability of the enzyme in concomitance with a decrease in the regular secondary structure acquired using CD spectrometry. This data clearly prove that the new derivatives show a stronger inhibitory effect than the separate compounds. Molecular docking analysis showed that the best possible interaction condition was achieved for chrysin with n‐6. Practical applications MT is a suitable model in medicine for the investigation of melanogenesis, skin disorders, and hyperpigmentation because of its accessibility and close structural similarity to mammalian tyrosinase. In recent years, the designing of tyrosinase inhibitors from natural substances for prevention of hyperpigmentation in medicine, skin cosmetics, and undesired browning in agriculture and food industry has risen sharply. Many of the pharmaceutical products based on the use of flavonoids and poly unsaturated acids as natural compounds or on their semi‐synthetic derivatives have been interested for investigations because of their usefulness in many pathological conditions such as inflammation, cancer, and skin disorders. The limitation of the flavonoids applications are low bioavailability, permeability, and solubility for the cells. In this study, conjugation of chrysin with n‐3 and n‐6 fatty acids resulted in a stronger inhibitors of MT with a synergic inhibitory effect on its activity.

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The reaction of 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane-2,4-disulfide (Lawesson reagent) with isobutanol, cyclohexylamine and phenylethylamine produced (4-methoxy-phenyl)-phosphonodithioic acid o-isobutyl ester HS 2 P(p-C 6 H 4 OMe) (OCH 2 CH(CH 3) 2) (I), [S 2 P(C 6 H 11 NH)(p-C 6 H 4 OMe) H 3 N + C 6 H 11 ] (II) and [S 2 P(phCH 2 CH 2 NH) (p-C 6 H 4 OMe)H 3 N + CH 2 CH 2 ph] (III), respectively. The reaction of alcohol with Lawesson reagent produced neutral product (I) while that with amines led to an ion pair (II, III). Furthermore, reaction of I, II and III with NiCl 2 .6H 2 O in methanol produced novel complexes: IV, V and VI. The compounds were characterized by 1 H, 13 C and 31 P NMR, IR spectroscopy and elemental analysis. The single crystal X-ray structures of IV and V showed that the nickel complexes are square planar. Compound V formed a three-dimensional supramolecular structure via intermolecular P-O.. .H-N hydrogen bonds. The Xray crystallography of V showed that those three hydrogens of + NH 3 cation produced three hydrogen bonds with different distances. The new compounds were additionally tested in view of their anti-bacterial properties. The ligands containing amine substituents exhibited more activity toward tested bacteria than their alcohol substituents, while the Ni(II) complexes including alcohol substituents exhibited high potential.

A simple, descriptive and interpretable model, based on a quantitative structure-retention relationship (QSRR), was developed using the genetic algorithm-multiple linear regression (GA-MLR) approach for the prediction of the retention indices (RI) of essential oil components. By molecular modeling, three significant descriptors related to the RI values of the essential oils were identified. A data set was selected consisting of the retention indices for 32 essential oil molecules with a range of more than 931 compounds. Then, a suitable set of the molecular descriptors was calculated and the important descriptors were selected with the aid of the genetic algorithm and multiple regression method. A model with a low prediction error and a good correlation coefficient was obtained. This model was used for the prediction of the RI values of some essential oil components which were not used in the modeling procedure.

The water distillated essential oil of Citruslimon collected from Ramsar, Province of Mazandaran, North of Iran collected in December 2013, was analyzed using gas chromatography (GC) and gas chromatography-mass spectroscopy (GC-MS). The yield of oil was 0.23% w/w. Twenty-one components representing 100% of the essential oil were characterized. Limonene (61.4%), b-pinene (13.1%) and g-terpinene (11.3%) were identified as the main constituents in the volatile oil. The antioxidant ability of the oil was examined by free radical scavenging method using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical at different concentration of the oil. The Citruslimon oil exhibited free-radical-scavenging properties with IC50 value of 284.71µg ml -1 .