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A defatted extract of Polyalthia longifolia var. pendula root bark (PRB) in 50% methanol showed a significant ability to reduce blood pressure. It caused a 22% and 47% fall in mean arterial blood pressure (MABP) in rats at doses of 3 mg/kg and 30 mg/kg, respectively. Compounds purified from this extract include kolavenic acid (3), clerodane (1) and its isomer (2), liriodenine (4), lysicamine (5) and bisclerodane imide (6) and its isomer (7). Of these, only kolavenic acid produced a 22% fall in MABP, at a dose of 30 mg/kg. PRB showed a decrease in blood pressure of normotensive and egg yolk induced hypertensive rats. The LD50 of PRB was determined as 100 mg/kg in mice.

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Somina (herbal preparation) prepared by Hamdard Laboratories (Waqf) Pakistan is a mixture of five different medicinal plants, widely prescribed for the treatment of mental illness. For acute toxicity, the Karber arithmetic method for the calculation of LD50 and Hodge and Sterner toxicity scale was used. In this study, different doses (10, 100, 285, 500, 1000, 5000 and 10,000 mg/kg) of the extract was administered orally to the different groups of rats and mice. Signs of toxicity and possible death of animals were monitored for 24 hrs to calculate the median lethal dose (LD50) of somina. At the end of the study, all the animals in all the dose groups were sacrificed and the internal organ-body was compared with values from the control group. The LD50 was found to be >10,000 mg/kg body weight upon oral administration in mice and rats as no mortality was observed after single dose administration. According to Hodge and Sterner toxicity scale, the obtained value of LD 50 > 10,000 mg/kg classified the Somina as Practically non-toxic herbal medicine.

The comparative effects of coffee robusta and coffee arabica (Qahwa) on different attention and memory related assignments were measured in a double-blind study of 300 healthy young adult women who were randomly assigned to one of three different drinks: Group I (coffee robusta sachet dissolved in 100 ml of hot water): Group II (coffee arabica): and group III (100 ml water only). Cognitive function was assessed by standardized tests. Several monitoring cognitive tests and tasks were specifically chosen and performed to investigate the comparative effects of coffee robusta (CR) and coffee arabica (Qahwa; AC) on sleepiness (sleep and clear headed scale), attention (trail A & B, symbol digit, letter cancellation), general cognitive ability (stroop test) and memory (card test). Data was interpreted by analysis of variance (ANOVA). The present study revealed that coffee robusta has beneficial effects on attention, general cognitive ability and memory. Higher though non-significant cognitive scores were associated with coffee robusta consumption. Although, consumption of coffee arabica (Qahwa) has significant effects (P < 0.05) on sleepiness, attention, general cognitive ability and memory and it significantly improve reaction time and correct responses. Since different tasks were related to the sustained attention and working memory processes, results would suggest that coffee arabica (qahwa) could increase the memory and efficiency of the attentional system might be due to the presence of chlorogenic acids (CGA) which are found in less quantity in coffee robusta. However, more studies using larger samples and different tasks are necessary to better understand the effects of coffee robusta and arabica (Qahwa) on attention and memory.

Towards optimization of the pyrrolizine-5-carboxamide scaffold, a novel series of six derivatives (4a-c and 5a-c) was prepared and evaluated for their anti-inflammatory, analgesic and anticancer activities. The (EZ)-7-cyano-6-((4-hydroxybenzylidene)amino)-N-(p-tolyl)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (4b) and (EZ)-6-((4-chlorobenzylidene)-amino)-7-cyano-N-(p-tolyl)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (5b) bearing the electron donating methyl group showed the highest anti-inflammatory activity while (EZ)-6-((4-chlorobenzylidene)amino)-7-cyano-N-phenyl-2,3-dihydro-1H-pyrrolizine-5-carboxamide (5a) was the most active analgesic agent. Cytotoxicity of the new compounds was evaluated against the MCF-7, A2780 and HT29 cancer cell lines using the MTT assay. Compounds 4b and 5b displayed high anticancer activity with IC50 in the range of 0.30–0.92 μmol L−1 against the three cell lines, while compound (EZ)-N-(4-chlorophenyl)-7-cyano-6-((4-hydroxybenzylidene)-amino)-2,3-dihydro-1H-pyrrolizine-5-carboxamide (4c) was the most active against MCF-7 cells (IC50 = 0.08 μmol L−1). Both the anti-inflammatory and anticancer activities of the new compounds were dependent on the type of substituent on the phenyl rings. Substituents with opposite electronic effects on the two phenyl rings are preferable for high cytotoxicity against the MCF-7 and A2780 cells. COX inhibition was suggested as the molecular mechanism of the anti-inflammatory activity of the new compounds while no clear relationship could be observed between COX inhibition and anticancer activity. Compound 5b, the most active against the three cell lines, induced dose-dependent early apoptosis with 0.1–0.2 % necrosis in MCF-7 cells. New compounds showed promising drug-likeness scores while the docking study revealed high binding affinity to COX-2. Taken together, this study highlighted the significant impact of the substituents on the anti-inflammatory and anticancer activity of pyrrolizine-5-carboxamides, which could help in further optimization to discover good leads for the treatment of cancer and inflammation.

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Hypotensive effects of aloeemodin, aloin A, elgonica dimer A and bisbenzopyran from Aloe barbadensis have been studied. Aloeemodin has emerged as a potent hypotensive agent in current pharmacological investigations and caused 26 %, 52 %, and 79 % falls in mean arterial blood pressure at the corresponding doses of 0.5, 1, and 3 mg/kg in rats. The paper also describes the absolute configuration of elgonica dimer A (1).