ABSTRACT Hyoscyamus insanus (family Solanaceae) was traditionally used for treatment of asthma, relieving pain and increasing female body weight. The present project was intended to assess the phytochemicals, total phenolic content, cytotoxic, antioxidant and antidiabetic activities of Hyoscyamus insanus leaves methanolic extract and its special fractions. After extraction, the methanolic extract was sequentially fractionated with n -hexane, chloroform and water followed by phytochemicals analysis of each sample. Brine shrimp lethality bioassay, Folin-Ciocalteu phenol reagent, DPPH, ABTSo+, H2O2 and alpha-amylase inhibition assays were employed for the assessment of cytotoxic property, total phenolic content, antioxidant and anti-diabetic potency of methanolic extract and its fractions. Amino acids and protein, carbohydrates, flavonoids and saponins were found in the methanolic extract and aqueous fraction while chloroform fraction exhibited carbohydrates, flavonoids and saponins. The highest cytotoxic activity (80.6±1.2%) was exhibited by methanolic extract while maximum total phenolic content (21.93±1.17 mg GAE/g) were found in the chloroform fraction. The employed antioxidant assays expressed different results i.e. methanolic extract demonstrated highest; 83.99%, 74.19% and 51.15% free radical scavenging characteristics in ABTS, DPPH and H2O2 assays respectively. The methanolic extract showed significant (53.44%) antidiabetic properties. The correlation of total phenolic content with percentage antioxidant and anti-diabetic capabilities of methanolic extract and its special fractions was observed to be non-significant (P > 0.05). It is concluded that the Hyoscyamus insanus is a potential source of phenolic, cytotoxic, antioxidant and antidiabetic compounds.

Abstract Background: The venom of the krait (Bungarus sindanus), an Elapidae snake, is highly toxic to humans and contains a great amount of acetylcholinesterase (AChE). The enzyme AChE provokes the hydrolysis of substrate acetylcholine (ACh) in the nervous system and terminates nerve impulse. Different inhibitors inactivate AChE and lead to ACh accumulation and disrupted neurotransmission. Methods: The present study was designed to evaluate the effect of palladium(II) complex as antivenom against krait venom AChE using kinetics methods. Results: Statistical analysis showed that krait venom AChE inhibition decreases with the increase of Pd(II) complex (0.025-0.05 µM) and exerted 61% inhibition against the AChE at a fixed concentration (0.5 mM) of ACh. Kinetic analysis using the Lineweaver Burk plot showed that Pd(II) caused a competitive inhibition. The compound Pd(II) complex binds at the active site of the enzyme. It was observed that K m (Michaelis-Menten constant of AChE-ACh into AChE and product) increased from 0.108 to 0.310 mM (45.74 to 318.35%) and V max remained constant with an increase of Pd(II) complex concentrations. In AChE K Iapp was found to increase from 0.0912 to 0.025 µM (29.82-72.58%) and did not affect the V maxapp with an increase of ACh from (0.05-1 mM). K i (inhibitory constant) was estimated to be 0.029µM for snake venom; while the K m was estimated to be 0.4 mM. The calculated IC50 for Pd(II) complex was found to be 0.043 µM at constant ACh concentration (0.5 mM). Conclusions: The results show that the Pd(II) complex can be deliberated as an inhibitor of AChE.