This study, for the first time, has shown that capsaicin, a novel EPI, not only inhibits the NorA efflux pump of S. aureus but also reduces the invasiveness of S. aureus, thereby reducing its virulence.

The results of this study are suggestive of piperine's involvement in the inhibition of clinically overexpressed mycobacterial putative efflux protein (Rv1258c). Piperine may be useful in augmenting the antimycobacterial activity of rifampicin in a clinical setting.

Additionally, Al metal electrode is stable in open air under ambient condition, which is easier for manufacturing as compared to Li metal. Therefore, AIBs have been considered as a promising candidate for largescale energy storage in the future.However, the research progress in AIBs has been severely limited by developing new electrode and electrolyte. A key challenge is the sluggish Al 3+ ion diffusion in the host materials during electrochemical charge/discharge processes. Monovalent ions, such as Li + and Na + , could be easily inserted into and extracted from the host materials with a simultaneous charge transfer. [9] Owing to the three-electron transfer process in the charge/discharge reactions, the strong bonding between Al 3+ and the host materials would lead to slow diffusion kinetics in the host structures. In recent decades, aqueous electrolytes have been employed in AIBs. However, they deliver low discharge voltages and poor cell efficiencies. [10] Liu et al. developed copper hexacyanoferrate nanoparticles as cathode materials for AIBs in 0.5 m Al 2 (SO 4 ) 3 aqueous electrolyte, exhibiting low potential window of 0.2-1.2 V (vs SCE) and poor capacity retention of 54.9% after 1000 cycles. [9] Very recently, ionic liquid (IL) electrolyte was explored to replace aqueous electrolyte in AIBs. [8,11] For example, Wang et al. designed an AIB using pristine natural graphite flakes as an electrode with AlCl 3 /[EMIm]Cl as an electrolyte, achieving a high specific capacity of 110 mAh g −1 and Coulombic efficiency of 98%. [8] However, the obtained capacity is still far below the theoretical capacity. Therefore, it is urgent to develop new electrode materials with high specific capacity and good cyclability.Tin sulfides have attracted great attention as active materials for Li-ion and Na-ion batteries. [12] Especially, tin monosulfide (SnS, also called herzenbergite) is an important mineral on earth, which is chemically stable in the presence of water and oxygen. In addition, SnS is a typical layered material with a large interlayer spacing of 0.43 nm, which is available for the intercalation of alkali metal ions and compensation of the volume expansion during the charge/discharge process. [13] The layers of SnS are coupled by weak van der Waals forces, which are beneficial for reversible alkali metal ions storage. [14] Moreover, SnS presents excellent electric conductivities of 0.193 S and 0.063 S cm −1 in parallel and perpendicular to the basal plane, respectively. [15] Conventionally, carbonaceous materials and organic binders are widely employed in the fabrication of powder materialbased battery electrodes, which have low volumetric capacities and cannot meet the requirement for flexible energy storage.High-performance flexible batteries are promising energy storage devices for portable and wearable electronics. Currently, the major obstacle to develop flexible batteries is the shortage of flexible electrodes with excellent electrochemical performance. Another challenge is the limited progress in the flexible ...

A newly identified class of compounds derived from a natural amide, piperine, is more potent than the parent molecule in potentiating the activity of ciprofloxacin through the inhibition of the NorA efflux pump. These molecules may prove useful in augmenting the antibacterial activities of fluoroquinolones in a clinical setting.

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AbstractÐInhibitors of drug metabolism have important implications in pharmaco-toxicology and agriculture. We have reported earlier that piperine, a major alkaloid of black and long peppers inhibits both constitutive and inducible cytochrome P450 (CYP)-dependent drug metabolising enzymes. In the present study, an attempt has been made to prepare several novel synthetic analogues so as to relate various modi®cations in the parent molecule to the inhibition of CYP activities. Two types of mono-oxygenase reactions arylhydrocarbon hydroxylase (AHH) and 7-methoxycoumarin-O-demethylase (MOCD) have been studied. Inhibition studies were investigated in rat microsomal fraction prepared from untreated, 3MC-and PB-treated rat liver in vitro. Modi®ca-tions were introduced into the piperine molecule: (i) in the phenyl nucleus, (ii) in the side chain and (iii) in the basic moiety. Thus, 38 compounds have been subjected to such studies, and simultaneously an attempt has also been made to arrive at the structure± activity relationship of synthetic analogues. In general, most of the inhibitory potential of the parent molecule is lost with modi®cation in either of the three components of piperine. Saturation of the side chain resulted in signi®cantly enhanced inhibition of CYP while modi®cations in the phenyl and basic moieties in few analogues oered maximal selectivity in inhibiting either constitutive or inducible CYP activities. Thus few novel analogues as CYP inactivators have been synthesized which may have important consequences in pharmacokinetics and bioavailability of drugs. #

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