Antioxidant capacity and phenolic content of different solvent extracts from banana (Musa paradisiaca) and mustai (Rivea hypocrateriformis)

In the present study, chloroform, acetone, and methanol extracts from stem and flower of banana (Musa paradisiaca) and leaves, stem, and flowers of mustai (Rivea hypocrateriformis) were evaluated for their in vitro antioxidant activity using ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picryl-hydrazyl (DPPH^•), 2,2′azinobis (3-ethylbenzothiozoline-6-sulfonic acid) diammonium salt (ABTS^•+), iron chelation, and antihemolytic activity. Among the solvents used, methanol gave the maximum yield in banana, whereas in night glory acetone was reported to having higher extractive value. The total phenolic content was also higher in these extracts. The antioxidant potential of the extracts was well established with their DPPH^• and ABTS^•+ radical scavenging activities and ferric reducing antioxidant capacity. The potential of multiple antioxidant activity of samples can be further evidenced by inhibition of reactive oxygen mediated erythrocyte cell lysis and metal ion chelating activity. However, this is the first report on the antioxidant property of mustai and this plant is having excellent antioxidant potential over banana. In conclusion, the results implied that the leaves, stem, and flowers of banana, and mustai could be considered as health supplements and nutraceuticals/functional foods.     

Homologous recombination of a flanking repeat gene cluster is a mechanism for a common contiguous gene deletion syndrome

Smith-Magenis syndrome (SMS), caused by del(17)p11.2, represents one of the most frequently observed human microdeletion syndromes. We have identified three copies of a low-copy-number repeat (SMS-REPs) located within and flanking the SMS common deletion region and show that SMS-REP represents a repeated gene cluster. We have isolated a corresponding cDNA clone that identifies a novel junction fragment from 29 unrelated SMS patients and a different-sized junction fragment from a patient with dup(17)p11.2. Our results suggest that homologous recombination of a flanking repeat gene cluster is a mechanism for this common microdeletion syndrome.     

Silver nanoparticles distributed into polyaniline bridged silica network: A functional nanocatalyst having synergistic influence for catalysis

A novel organic–inorganic hybrid nanocatalyst, Ag nanoparticles supported poly[N-(3-Trimethoxy silyl)propyl]aniline (Ag@PTMSPA), was prepared by a simple one-step method. X-ray diffraction analysis, field emission transmission electron microscopy and X-ray photo electron spectroscopy reveal the coexistence of Ag nanoparticles (average size ∼ 10 nm) and PTMSPA in Ag@PTMSPA. N₂ adsorption–desorption experiments provide the textural properties of the catalyst, such as surface area (86.6 m²/g), pore volume (1.3 × 10^− 1 cm³/g) and pore size (4.2 nm). UV–visible spectroscopy was used to follow the kinetics of reduction of 4-nitrophenol (4-NP) by sodium borohydride (NaBH₄) in the presence of Ag@PTMSPA catalyst.     

Synthesis of Amido‐N‐imidazolium Salts and their Applications as Ligands in Suzuki–Miyaura Reactions: Coupling of Hetero‐ aromatic Halides and the Synthesis of Milrinone and Irbesartan

A new catalytic system based on palladium‐amido‐N‐heterocyclic carbenes for Suzuki–Miyaura coupling reactions of heteroaryl bromides is described. A variety of sterically bulky, amido‐N‐imidazolium salts were synthesized in high yields from the corresponding anilines. This catalytic system effectively promoted Suzuki–Miyaura couplings of heteroaryl bromides and chlorides with a range of boronic acids to give the corresponding aryl compounds in high yield. The yield was increased with increasing steric bulkiness of the substituted group. Especially, 1‐(2,6‐diisopropylphenyl)‐3‐N‐(2,4,6‐tri‐tert‐butylphenylacetamido)imidazolium bromide ( 4bc ) exhibited 850,000 TON in the coupling reaction of 2‐bromopyridine and phenylboronic acid. In addition, pharmaceutical compounds such as milrinone and irbesartan were synthesized via Suzuki–Miyaura coupling using sterically bulky, amido‐N‐imidazolium salt ( 4bc ) as a ligand.     

Antioxidant activity of lettuce tree (Pisonia morindifolia R.Br.) and tamarind tree (Tamarindus indica L.) and their efficacy in peanut oil stability

Different solvent extracts of lettuce tree (Pisonia morindifolia R. Br.) and tamarind tree (Tamarindus indica L.) were tested for antioxidant activities. The extracts exhibited effective reducing power and higher radical scavenging efficacy against DPPH and hydroxyl radicals. They also showed metal chelating ability and inhibited peroxidation in the β-carotene/linoleic acid emulsion system. The extracts contained considerable levels of vitamin C, vitamin E, total phenolics, tannins, and total flavonoids estimated through standard spectrophotometric methods. As the acetone and methanol extracts of lettuce and tamarind tree recorded pronounced activities, their protective effects in stabilizing peanut oil were tested in terms of their peroxide value, free fatty acid contents, and p-anisidine values in comparison with the synthetic antioxidants butylated hydroxyanisole and butylated hydroxytoluene. Additionally, the antioxidant activity of the extract-treated oil samples and their phenolic contents were monitored to obtain a complete perspective of the influence of the phenolic compounds in oil stability. Results indicated that the selected leafy vegetables, besides acting as good sources of antioxidants, may serve as substitute for synthetic antioxidants in the stabilization of peanut oil.     

Lead-free 0201 manufacturing, assembly and reliability test results

The trend towards smaller, faster and cheaper electronic devices has led to an increase in the use of 0201 (L  0.02 in.; W  0.01 in.) and even smaller sized passive components. The size advantages of the 0201 component make it a popular choice among design engineers but not among manufacturing engineers. From a manufacturing perspective, the size of the 0201 package poses significant challenges to the printed circuit board (PCB) assembly process. The many challenges with 0201 assembly can be attributed to the solder paste volume, pad design, aperture design, board finish, type of solder paste, pick-and-place and reflow profile. If these factors are not optimized, they will introduce undesirable manufacturing defects. The small size of 0201 packages and undetected manufacturing defects will also raise concerns about their second level interconnect reliability, especially for lead-free solder alloys and surface finishes, with new processes and higher reflow requirements. To determine the optimum conditions, a design-of-experiment (DOE) study was carried out to investigate the effects of these parameters on assembly defects and solder joint reliability.This paper presents the test results and comparative literature data on the influence of a few key manufacturing parameters and defects associated with the 0201 component using lead-free and tin–lead solder alloys. Data pertaining to component shear strength before and after isothermal aging at 150 °C and intermetallic growth up to 500 h of aging are presented. A number of test vehicles were also subjected to thermal cycling (1500 cycles) in the range of −55/100 °C to determine the solder fatigue behavior. Shear test results for test vehicles subjected to thermal cycling is also presented. In addition, optical microscopy analysis of solder joint behavior during thermal cycling showing the progress of the solder damage and cross-sectional photos taken at 1500 cycles is included.     

Nanostructuring of poly(diphenylamine) inside the galleries of montmorillonite organo clay through self-assembly approach

Hollow spheres of poly(diphenylamine) (PDPA) was prepared by confining PDPA in the galleries of montmorillonite organo clay modified with organoammonium cations (MMT). At first instant, diphenylamine (DPA) was loaded into the galleries of MMT and subjected to subsequent oxidative polymerization to form PDPA. beta-naphthalene sulfonic acid (NSA) was used as medium to influence self-assembly of DPA inside the galleries of MMT. Polymerization of self assembled structure resulted hollow spheres of PDPA inside galleries of MMT. X-ray diffraction analysis (XRD), field emission transmission electron microscopy (FETEM), Fourier transform infra-red spectroscopy (FT-IR) and thermogravimetric analysis (TGA) were used to characterize the composites. Transmission emission microscopy of the composite shows the hollow spherical morphology of PDPA. FT-IR, UV-Visible spectroscopy, conductivity measurement and X-ray photoelectron spectroscopy were used to characterize the PDPA extracted from MMT galleries. PDPA extracted from MMT galleries was found to have difference in electronic property than PDPA formed by the conventional method, due to the confinement effect.     

The influence of alkali pretreatments in lyocell resin finishing—Resin distribution and mechanical properties

Lyocell fabric samples were pretreated with NaOH and KOH and resin finished. The treated samples were tested to determine the influence of alkali pretreatments on the tenacity, abrasion resistance, and crease recovery of resin‐finished lyocell. Alkali pretreatments resulted in a higher surface concentration of the crosslinking reagent in fabrics, leading to lowered crease recovery and abrasion resistance. The pretreatments also exerted a deleterious influence on the tensile strength in resin‐finished samples. However, the differential distribution of crosslinking reagent within the textile structure does not appear to be the only factor responsible for the changes observed in substrate properties; other factors also appear to be responsible for the results observed. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 3596–3601, 2006     

Evaluation of edible flowers of agathi (Sesbania grandiflora L. Fabaceae) for in vivo anti-inflammatory and analgesic,and in vitro antioxidant potential

The methanol extract from flowers of agathi (Sesbania grandiflora L. Fabaceae) was evaluated for their in vitro antioxidant and cytotoxic activities, and in vivo anti-inflammatory and antinociceptive activities in several experimental models. The extract has sustainable concentrations of dietary polyphenolics, tannins, and flavonoids. The extract exhibited maximum radical scavenging activity on nitric oxide, superoxide, and hydroxyl radical and these values were significantly (p<0.05) higher over positive standards butylated hydroxyanisole and butylated hydroxytolune. The extract also exhibited potential cytotoxic activity against human cervical cancer cell line HeLa (IC₅₀ value of 0.13 mg/mL). Further, the methanol extracts showed significant inhibitory activity against inflammation (carrageenan and cotton pellet induced models) and on a pain model (hot plate test). The inhibitory values are comparable with positive standards. Owing to these properties, agathi flowers can be used as a potential source of natural nutraceutical food supplement.     

Investigation of the decomplexation of polyamide/CaCl2 complex toward a green,nondestructive recovery of polyamide from textile waste

The ‘circular economy’ concept envisages deriving the maximum value out of resources and reducing waste to a minimum. In textiles, that includes the recovery of fiber materials out of used clothing and reusing them in the construction of new clothes. Processes such as mechanical separation, depolymerization treatment, and selective dissolutions of individual polymers are applied. We investigate the approach of selective nondestructive dissolution and recovery of polyamide fiber from mixed textile waste by using the solvent system CaCl₂/ethanol/water (CEW) based on complexation and decomplexation of polyamide (PA). The results show that PA is precipitated and decomplexed by simple addition of water and a substantial amount of previously incorporated calcium by complexation, is removed. The recovered polyamide shows properties similar to pristine polyamide. Investigation on a mixed textile waste model of polyamide/wool demonstrates that CEW treatment can successfully separate different fiber materials. The nondestructive approach in dissolving PA using CEW, clearly shows the benefit, that PA fiber can be separated by controlled complexation/decomplexation without degradation, thus avoiding the repolymerization step. Furthermore, the solvent system is made of abundantly available materials that are inexpensive and used widely in industrial-scale operations. Thus, the concept will make significant contribution to a green textile recycling approach.