Braj B. Singh

Lycopene content, antioxidant capacity and colour attributes of selected watermelon (Citrullus lanatus (Thunb.) Mansfeld) cultivars grown in India

The present investigation reports variability in lycopene, ascorbic acid, total phenolics, antioxidant capacity and colour attributes of 12 watermelon cultivars grown in India. Antioxidant capacity was evaluated using four in vitro assays, namely ferric reducing antioxidant power, cupric reducing antioxidant capacity, Trolox equivalent antioxidant capacity and 2,2-diphenyl-1-picryl hydrazyl. Among watermelon cultivars, significant differences (p < 0.05) were found with respect to lycopene content and antioxidant capacity. Lycopene content ranged from 03.46 to 8.00 mg/100 g fresh weight. Colour of watermelon flesh was described by an optimized colour index (CI). Cultivars ‘PWM25-4’, ‘Arun’, ‘Kiran’ and ‘Kareena’ were found to be the most promising ones with highest lycopene content, antioxidant capacity and CI. Results indicate that watermelon is a good source of dietary lycopene and there exists significant variation that can be exploited to produce high-quality cultivars.

Lipase-Catalyzed Solvent-Free Amidation of Phenolic Acids

Abstract A series of N-alkyl-substituted amides, based on various phenolic acids, have been synthesized by the condensation of equimolar amounts of phenolic acids with different alkyl amines in the presence of Candida antarctica lipase at 60–90 °C in 16–20 h. The reactions were carried out in a solvent-free system without the use of any activating agents. All the products were obtained in appreciable amounts and the yields for different compounds varied between 75.6% and 83.5%. The synthesized compounds were characterized using spectroscopy techniques, namely infrared and NMR (1H and 13C). GRAPHICAL ABSTRACT

Development of controlled release nanoformulations of carbendazim employing amphiphilic polymers and their bioefficacy evaluation against Rhizoctonia solani

Controlled release nanoformulations of carbendazim (Methyl 1H-benzimidazol-2-ylcarbamate), a systemic fungicide, have been prepared using laboratory synthesized poly(ethylene glycols) (PEGs)-based functionalized amphiphilic copolymers. The release kinetics of carbendazim from developed controlled release (CR) formulations was studied and compared with that of the commercially available 50% Wettable Powder (WP). Further, the bioefficacy evaluation of developed formulations was done against plant pathogenic fungi Rhizoctonia solani by the poison food technique method. The release of maximum amount of carbendazim from developed formulations was dependent on the molecular weight of PEGs and was found to increase with increasing molecular weights. The range of carbendazim release was found to be between 10th to 35th day as compared to commercial formulation which was up to 7th day. The diffusion exponent (n value) of carbendazim in water ranged from 0.37 to 0.52 in the tested formulations. The half-release (t1/2) values ranged between 9.47 and 24.20 days, and the period of optimum availability (POA) of carbendazim ranged from 9.15 to 26.63 days. Also, ED50 values of the developed formulations vary from 0.40 to 0.74 mg L−1. These formulations can be used to optimize the release of carbendazim to achieve disease control for the desired period depending on the matrix of the polymer used.

Eco-friendly PEG-based controlled release nano-formulations of Mancozeb: Synthesis and bioefficacy evaluation against phytopathogenic fungi Alternaria solani and Sclerotium rolfsii

ABSTRACT Controlled release (CR) nano-formulations of Mancozeb (manganese-zinc double salt of N,N-bisdithiocarbamic acid), a protective fungicide, have been prepared using laboratory-synthesized poly(ethylene glycols) (PEGs)-based functionalized amphiphilic copolymers without using any surfactants or external additives. The release kinetics of the developed Mancozeb CR formulations were studied and compared with that of commercially available 42% suspension concentrate and 75% wettable powder. Maximum amount of Mancozeb was released on 42nd day for PEG-600 and octyl chain, PEG-1000 and octyl chain, and PEG-600 and hexadecyl chain, on 35th day for PEG-1000 and hexadecyl chain, on 28th day for PEG-1500 and octyl chain, PEG-2000 and octyl chain, PEG-1500 and hexadecyl chain, and PEG-2000 and hexadecyl chain in comparison to both commercial formulations (15th day). The diffusion exponent (n value) of Mancozeb in water ranged from 0.42 to 0.62 in tested formulations. The half-release (t1/2) values ranged from 17.35 to 35.14 days, and the period of optimum availability of Mancozeb ranged from 18.54 to 35.42 days. Further, the in vitro bioefficacy evaluation of developed formulations was done against plant pathogenic fungi Alternaria solani and Sclerotium rolfsii by poison food technique. Effective dose for 50% inhibition in mgL−1 (ED50) values of developed formulations varied from 1.31 to 2.79 mg L−1 for A. solani, and 1.60 to 3.14 mg L−1 for S. rolfsii. The present methodology is simple, economical, and eco-friendly for the development of environment-friendly CR formulations of Mancozeb. These formulations can be used to optimize the release of Mancozeb to achieve disease control for the desired period depending upon the matrix of the polymer used. Importantly, the maximum amount of active ingredient remains available for a reasonable period after application. In addition, the developed CR formulations were found to be suitable for fungicidal applications, allowing use of Mancozeb in lower doses.

Synthesis and Characterization of Novel Encapsulating Materials Based on Functionalized Amphiphilic Block Copolymers

The synthesis and characterization of eight novel PEG-based amphiphilic block copolymers is reported. The polymers have been synthesized by reacting poly(ethylene glycols) (PEGs) of different molecular weights viz. 600, 1000, 1500 and 2000 and dimethyl 5-hydroxyisophthalate in the presence of concentrated H2SO4 as catalyst and further alkylating the resulting polymers by attaching heptyl and tetradecyl chains to phenolic hydroxyl group. The resulting functionalized amphiphilic polymers have been characterized by 1H and 13C-NMR spectroscopy. These polymers, when dissolved in water, aggregate to form micelles, giving size ranging from 26.50 to 85.10 nm as determined by Dynamic Light Scattering (DLS) instrument. The molecular weights have been also calculated from the DLS and are in the range 8.8 × 103 to 8.5×104 KDa (Kilo Daltons). Critical Micelle Concentrations (CMC) of the synthesized polymers was determined using electrical conductivity meter with values in the range 115 to 148 mgL−1 (milligrams per litre).

Synthesis and characterization of functionalized amphiphilic polymers for utilization as surfactants

ABSTRACT Eight novel PEG-based amphiphilic block copolymers having self-assembling properties has been reported in the present study. The polymers have been synthesized by reacting Poly(ethylene glycols) (PEGs) of different molecular weights viz. 600, 1000, 1500 and 2000 and dimethyl-5-hydroxyisophthalate in presence of concentrated H2SO4 as catalyst in solventless condition at 80–90°C and further alkylating the resulting polymers by attaching octyl and hexadecanyl chains to phenolic hydroxyl group. The resulting functionalized amphiphilic polymers have been characterized by 1H and 13C-NMR spectroscopy. These polymers, when dissolved in water, aggregate to form micelles, giving sizes ranging from 13.00 to 87.24 nm as determined by Dynamic Light Scattering (DLS) instrument. The molecular weights have been also calculated from the DLS and are in the range 3.5×104 to 1.8×106 KDa (Kilo Daltons). Critical Micelle Concentrations (CMC) of the synthesized polymers was determined using electrical conductivity meter with values in the range of 105 to 138 mg L−1 (milligrams per litre).

Synthesis and Characterization of Amphiphilic PEG Based Polymers and Their Self Assembling Behavior

Sixteen amphiphilic polymers were synthesized using poly(ethylene glycols) (PEGs) of different molecular weights, viz. 1000, 1500, 2000 and 4000 as hydrophilic block and linkers namely azelaic acid, suberic acid, terephthalic acid and glycolic acid as hydrophobic block in the presence of catalyst conc. H2SO4 out of which four with glycolic acid as linker are new. Synthesized polymers were characterized by using 1H-NMR, 13C-NMR and IR spectroscopy. Micellar sizes of the polymers were determined using Dynamic Light Scattering (DLS) technique which ranged from 32.1–262.0 nm and confirmed by Transmission Electron Microscope (TEM) analysis. Molecular weights were determined using HORIBA SZ-100 scientific and varied from 6.5 × 102 to 6.5 × 103 Kilo Daltons(kDa) by Debye plot. Critical Micelle Concentrations (CMC) of the synthesized polymers was determined using electrical conductivity meter and it ranged from 105 to 125 milligrams per litre (mg L−1).

Mineral Profiling and Phytochemical Assessment of Lepidium sativum Seeds from Tropical Western India

In recent years, the use of crude medicinal plants assures health promoting effects in humans and animals due to its useful and effective bioactive principles without any side effects. As a great physician, Hippocrates (460-370 B.C.) quoted “Let food be thy medicine and medicine be thy food”. Also, same thing was reported in a book, Drug may not be the only cure for disease; food is our best medicine (Bieler, 2010). Therefore, medicinal plants are still a major area of research for their beneficial uses (Bauri et al., International Journal of Current Microbiology and Applied Sciences ISSN: 2319-7706 Volume 7 Number 08 (2018) Journal homepage: http://www.ijcmas.com