No abstract

We investigated the efficacy of rosmarinic acid (RA) in preventing lipid peroxidation and increased activity of acetylcholinesterase (AChE) in the brain of streptozotocin-induced diabetic rats. The animals were divided into six groups (n = 8): control, ethanol, RA 10 mg/kg, diabetic, diabetic/ethanol and diabetic/RA 10 mg/kg. After 21 days of treatment with RA, the cerebral structures (striatum, cortex and hippocampus) were removed for experimental assays. The results demonstrated that the treatment with RA (10 mg/kg) significantly reduced the level of lipid peroxidation in hippocampus (28%), cortex (38%) and striatum (47%) of diabetic rats when compared with the control. In addition, it was found that hyperglycaemia caused significant increased in the activity of AChE in hippocampus (58%), cortex (46%) and striatum (30%) in comparison with the control. On the other hand, the treatment with RA reversed this effect to the level of control after 3 weeks. In conclusion, the present findings showed that treatment with RA prevents the lipid peroxidation and consequently the increase in AChE activity in diabetic rats, demonstrating that this compound can modulate cholinergic neurotransmission and prevent damage oxidative in brain in the diabetic state. Thus, we can suggest that RA could be a promising compound in the complementary therapy in diabetes.

Nanotechnology is one of the most recent technologies. It is uncertain whether the production of small-size nanoparticles (NPs) can be achieved through a simple, straightforward, and medicinally active phytochemical route. The present study aimed to develop an easy and justifiable method for the synthesis of Ag, Au, and their Ag/Au bimetallic NPs (BNPs) by using Hippeastrum hybridum (HH) extract, and then to investigate the effects of Ag, Au, and their Ag/Au BNPs as antimicrobial and phytotoxic agents. Ag, Au, and their Ag/Au BNPs were characterized by UV-visible spectroscopy, FT-IR spectroscopy, XRD, EDX, and SEM analysis. XRD analysis conferring to the face of face-centered cubic crystal structure with an average size of 13.3, 10.72, and 8.34 nm of Ag, Au, and Ag/Au BNPs, respectively. SEM showed that Ag, Au, and Ag/Au BNPs had spherical morphologies, with calculated nano measurements of 40, 30, and 20 nm, respectively. The EDX analysis confirmed the composition of elemental Ag signal of the HH-AgNPs with 22.75%, Au signal of the HH-AuNPs with 48.08%, Ag signal with 12%, and Au signal with 38.26% of the Ag/Au BNPs. The Ag/Au BNPs showed an excellent antimicrobial efficacy against Gram-positive Staphylococcus aureus, Actinomycetes meriye, Bacillus cereus, Streptococcus pyogenes, Methicillin-resistant Staphylococcus aureus, Micrococcus luteus, Streptococcus pneumonia, and Gram-negative Klebsiella pneumonia, Escherichia coli, and Serratia marcescens bacterial strains, as well as against three fungal strains (Aspergillus niger, Aspergillus fumigatus, and Aspergillus flavus) compared to HH extract, HH-AgNPs, and HH-AuNPs. However, further investigations are recommended to be able to minimize potential risks of application.

In the present study, we investigated the efficiency of rosmarinic acid (RA) in preventing the alteration of oxidative parameters in the liver and kidney of diabetic rats induced by streptozotocin (STZ). The animals were divided into six groups (n = 8): control, ethanol, RA 10 mg/kg, diabetic, diabetic/ethanol, and diabetic/RA 10 mg/kg. After 3 weeks of treatment, we found that TBARS levels in liver and kidney were significantly increased in the diabetic/saline group and the administration of RA prevented this increase in the liver and kidney (P < 0.05). Diabetes caused a significant decrease in the activity of superoxide dismutase (SOD) and catalase (CAT) in the diabetes/saline group (P < 0.05). However, the treatment with 10 mg/kg RA (antioxidant) prevented this alteration in SOD and CAT activity in the diabetic RA group (P < 0.05). In addition, RA reverses the decrease in ascorbic acid and non-protein-thiol (NPSH) levels in diabetic rats. The treatment with RA also prevented the decrease in the Delta-aminolevulinic acid dehydratase (ALA-D) activity in the liver and kidney of diabetic rats. Furthermore, RA did not have any effect on glycemic levels. These results indicate that RA effectively reduced the oxidative stress induced by STZ, suggesting that RA is a potential candidate for the prevention and treatment of pathological conditions in diabetic models.

Nanotechnology is one of the modern techniques of material science which have received much importance in the last many years. Nanotechnology is concerned with the production of nanoparticles (NPs) with restricted sizes and shapes through a facile, straightforward, and medicinally active phytochemical route. This study aims to develop an easy and justifiable method for the green synthesis of HH AgNPs using Hippeastrum hybridum (HH) extract and then to investigate the effects of HH AgNPs as a free radical scavenger, and an inhibitor of the two enzymes i‐e Alpha‐amylase (α‐amylase) and acetylcholinesterase (AChE). UV‐Vis spectrum at 432 nm with maximum absorbance at 1.98 confirmed the AgNPs formation. Fourier transform infrared spectroscopy (FT‐IR) conformed to the peaks for the functional groups of HH extract and on the surface of HH AgNPs that are involved in the synthesis and stability of the HH AgNPs. The average size of 13.3 nm for AgNPs was calculated using four major peaks at 37.92°, 43.79°, 64.27°, and 77.18° of X‐Rays Diffraction (XRD) analysis. The scanning electron microscope (SEM) analysis confirmed the presence of spherical shaped, monodispersed, and huge density AgNPs with an average 40 nm size of AgNPs. Energy dispersive X‐ray (EDX) confirmed the intense sharp peak at 3.1 keV showing that silver was the main element (22.75%). The HH AgNPs showed an excellent %scavenging of Ferric chloride (75.5 ± 0.014%), Ammonium molybdenum (72.1 ± 0.0021%), DPPH (69.6 ± 0.059%), H2O2 (65 ± 0.001%), and ABTS (68.3 ± 0.07%). Statistical analysis indicated HH AgNPs caused a non‐competitive type of inhibition (Km constant and Vmax decrease) against α‐amylase and AChE. Our results suggest that AgNPs exhibited significant antioxidant, antidiabetic, and antialzheimer activities in a concentration‐dependent manner as compared to AgNO3 and plant extract. However, further investigations are recommended to be able to minimize potential risks of application.