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Luffa aegyptiaca (Gourd) Fruit Juice as a Source of Peroxidase  [PDF]
R. S. S. Yadav,K. S. Yadav,H. S. Yadav
Enzyme Research , 2011, DOI: 10.4061/2011/319105
Abstract: Peroxidases have turned out to be potential biocatalyst for a variety of organic reactions. The research work reported in this communication was done with the objective of finding a convenient rich source of peroxidase which could be used as a biocatalyst for organic synthetic reactions. The studies made have shown that Luffa aegyptiaca (gourd) fruit juice contains peroxidase activity of the order of 180 enzyme unit/mL. The values of this peroxidase for the substrates guaiacol and hydrogen peroxide were 2.0 and 0.2?mM, respectively. The pH and temperature optima were 6.5 and 60°C, respectively. Like other peroxidases, it followed double displacement type mechanism. Sodium azide inhibited the enzyme competitively with value of 3.35?mM. 1. Introduction Peroxidase (E.C. 1.11.1.7) is a heme-containing enzyme, which catalyses the oxidation of a wide variety of organic and inorganic substrates using hydrogen peroxide as the electron acceptor [1, 2]. Peroxidases are widely distributed in living organisms including microorganisms, plants, and animals [3]. It is mainly located in the cell wall [4], and it is one of the key enzymes controlling plant growth and development. It is involved in various cellular processes including construction, rigidification, and eventual lignifications of cell walls [5], suberization [6], organogenesis [7], phenol oxidation [8], crosslinking of cell wall proteins [9], and protection of tissue from damage and infection by pathogenic microorganisms [10–12]. It is also used in clinical diagnosis and microanalytical immunoassays because of its high sensitivity. Apart from these applications, peroxidases have been used for biotransformations in organic synthesis [13]. Recent studies have revealed that not all peroxidases are similar in their structures and functions [14–21]. Lignin peroxidase differs from horseradish peroxidase in the sense that lignin peroxidase directly oxidizes veratryl alcohol whereas horseradish peroxidase cannot [17]. Soyabean peroxidase [17] has lignin peroxidase type activity, but it is more stable at acidic pH and at higher temperatures than the lignin peroxidase. During last decades, peroxidases have turned out to be potential biocatalysts [22] for variety of organic reactions, for example, enantioselective reduction of hydroperoxides [23], hydroxylation of arenes [24], epoxidation of olefins [20], halogenation [25], N-oxidation [26], and sulfoxidation [27]. The studies reported in this communication were performed with the objective of finding a convenient rich source of peroxidase which could be tested for
Enzymatic Characterisation of Lignin Peroxidase from Luffa aegyptiaca Fruit Juice  [PDF]
Nivedita Rai, Meera Yadav, Hardeo Singh Yadav
American Journal of Plant Sciences (AJPS) , 2016, DOI: 10.4236/ajps.2016.73057
Abstract: Luffa aegyptiaca fruit has been assayed for the presence of lignin peroxidase activity using veratryl alcohol as the substrate. The fruit juice contained activity of 3.14 U/ml which was much higher than 0.075 U/ml reported in the culture filtrate of Phanarochaete chrysosporium ATCC-24725. The Km value of the lignin peroxidase using veratryl alcohol as the variable substrate in 50mM phosphate buffer pH 2.5 at 25°C was found to be 50 μM respectively. The pH and temperature optima of the lignin peroxidase were 2.4 and 22°C, respectively. The present article reports viable method to explore rich sources of lignin peroxidase from plants which can be used as a mediator in oxidative organic transformations within green chemistry domain ensuring ecofriendly synthesis of bioorganic molecules of pharmaceutical value.
Foraging dynamics and pollination efficiency of Apis mellifera and Xylocopa olivacea on Luffa aegyptiaca Mill (Cucurbitaceae) in southern Ghana  [cached]
Mensah, Ben
Journal of Pollination Ecology , 2011,
Abstract: As a result of different levels of pollination efficiency of pollinators, knowledge on appropriate pollinators of a plant has become important, especially in the management and conservation of both the pollinators and the plants. In this study, the pollination efficiency of Apis mellifera and Xylocopa olivacea, important pollinators of Luffa aegyptiaca, were assessed in the southern coastal part of Ghana from June 2009 to September 2010. Pollination efficiency of A. mellifera and X. olivacea was estimated in terms of fruit set and fruit size. Further, data on daily and seasonal nectar dynamics of Luffa aegyptiaca were collected. In the early mornings (0600-0700), X. olivacea was the most frequent visitor (0.47 min-1) on the female flowers compared to A. mellifera (0.13 min-1). The mean nectar (sugar) concentration in the dry season was 36.58 ± 0.55 %, which was higher than the 34.03 ± 0.38 % obtained for the rainy season (F = 14.986; df = 2; P < 0.0001). Total amount of sugar in the early mornings was 1.88 ± 0.37 mg which was higher than 0.28 ± 0.04 mg in the mid mornings (χ2 = 14.33, df = 1, P < 0.0001). Fruits that developed from flowers that had received a single visit from X. olivacea had a mean weight of 428.7g and were 1.5 times heavier than fruits from flowers visited by A. mellifera (286.76 g). X. olivacea was more efficient than A. mellifera in terms of number of fruit set per single visit. This study has provided some knowledge on pollination ecology of L. aegyptiaca, which can be exploited to improve fruit production in commercially grown vine crops.
Physico-Mechanical Properties of Luffa aegyptiaca Fiber Reinforced Polymer Matrix Composite  [PDF]
S. I. Ichetaonye, I. C. Madufor, M. E. Yibowei, D. N. Ichetaonye
Open Journal of Composite Materials (OJCM) , 2015, DOI: 10.4236/ojcm.2015.54014
Abstract: This paper presents the study of moisture content, hardness, bulk density, apparent porosity, tensile and flexural characteristics of composite properties of Luffa aegyptiaca fiber. Luffa aegyptiaca reinforced epoxy composites have been developed by hand lay-up method with Luffa fiber untreated and treated conditions for 12 Hrs and 24 Hrs in different filler loading as in 2:1 ratio (5%, 10%, 15%, 20% and 25%). The effects of filler loading on the moisture content, hardness, bulk density, apparent porosity, tensile and flexural properties were studied. In general, the treated Luffa fibre composite for 24 Hrs showed better improvement properties via addition of modified Luffa fibre as reinforcement. However, tensile and flexural properties improved continuously with increasing filler loading up to 20% but decreasing at 25% due to weak interfacial bonding for both untreated and treated composite. The favourable results were obtained at 20% for treated composite at 24 Hrs especially at tensile and flexural characteristics and are suitable for mechanical applications.
STUDIES ON THE ANTIBACTERIAL AND ANTIFUNGAL ACTIVITIES OF THE ETHANOLIC EXTRACTS OF LUFFA CYLINDRICA (Linn) FRUIT
G.SASHIKALA DEVI, A.KOTTAI MUTHU, D.SATHEESH KUMAR, S.REKHA, INDHUMATHY AND R. NANDHINI
International Journal of Drug Development & Research , 2009,
Abstract: To investigate the antibacterial and antifungal activities of Ethanolic extract of Luffa cylindrica (Linn). The extract wasprepared from fresh fruit of Luffa cylindrica by hot continuous percolation method in Soxhlet apparatus. Ethanolic extractof Luffa cylindrica (Linn) were tested for antibacterial and antifungal efficacy against Gram positive & Gram negativebacteria and Aspergillus fumigates, Aspergillus niger and Candida albicans organism. The Ethanolic extract was found tobe the most effective and showed antibacterial and antifungal activity against the entire organism tested. The Zone ofInhibition (mm) at various concentrations of Ethanolic extract of Luffa cylindrica was found to the range 50 mg/ml to150mg/ml on tested all the test organisms. This study scientifically supports the usage of whole plant as a remedy forvarious superficial bacterial and fungal infections in traditional medicine.
Nematocidal Compounds from the Seeds of Balanites aegyptiaca Isolation and Structure Elucidation  [PDF]
C. Gnoula,P. Guissou,P. Duez,M. Frederich
International Journal of Pharmacology , 2007,
Abstract: The research aims are to characterize this anthelmintic activity and to isolate the main nematocidal agent of Balanties aegyptiaca plant. The anthelmintic activity was evaluated in vitro by means of an original anthelmintic assay using Caenorhabditis elegans as a biological model. Fluorescence microscopy was used for the determination of the percentage of worms death. The structure elucidation was based on NMR, mass spectroscopic analysis and chemical methods. A bioassay-directed fractionation of the aqueous extract of Balanites aegyptiaca led to the isolation of balanitin-7 (also named diosgenin 3β-O-β-D-xylopyranosyl-(1→3)-β-D-glucopyranosyl-(1→4)-[α-L-rhamnopyranosyl-(1→2)]-β-D-glucopyranoside), as being the principal nematicidal agent. These data indicate that balanitin-7 has an appreciable nematocidal activity, which is not mediated by inducing an anti-acetylcholinesterase activity.
A Physical Mechanism Underlying the Increase of Aqueous Solubility of Nonpolar Compounds and the Denaturation of Proteins upon Cooling  [PDF]
Sergey V. Buldyrev,Pradeep Kumar,H. Eugene Stanley
Physics , 2007,
Abstract: The increase of aqueous solubility of nonpolar compounds upon cooling and the cold denaturation of proteins are established experimental facts. Both phenomena have been hypothesized to be related to restructuring of the hydrogen bond network of water around small nonpolar solutes or hydrophobic amino acid side chains. However, an underlying physical mechanism has yet to be identified. We assume the solute particles and the monomers of a polymer interact via a hard sphere potential. We further assume that the solvent molecules interact via the two-scale spherically symmetric Jagla potential, which qualitatively reproduces the anomalies of water, such as expansion on cooling. We find that this model correctly predicts the increase in solubility of nonpolar compounds and the swelling of polymers on cooling. Our findings are consistent with the possibility that the presence of two length scales in the Jagla potential--a rigid hard core and a more flexible soft core--is responsible for both phenomena. At low temperatures, the solvent particles prefer to remain at the soft core distance, leaving enough space for small nonpolar solutes to enter the solvent thus increasing solubility. We support this hypothesized mechanism by molecular dynamic simulations.
Identification and antibacterial activity of methanol extract of Luffa acutangula Roxb.  [cached]
Resmi Mustarichie,Zalinar Udin,Muchtaridi,Supriyatna
Medical and Health Science Journal , 2012,
Abstract: Antibacterial activity of Luffa acutangula Roxb. (angled luffa) has been assayed against some pathogenic bacterial. Fruit powder of angled luffa was macerated with methanol, and the methanol extract extracted sequentially with hexane, chloroform, ethyl acetate and buthanol. Antibacterial activity was evaluated by well diffusion method. Extract with the highest antibacterial activity was identified regarding their class of compounds using phytochemical screening and Thin Layer Chromatography (TLC) method. The antibacterial activity of the extract was compared with that of the ampicillin used. The methanol extract inhibited the growth of the P. aeruginosa, E. Coli, B. Subtilis and S.aureus, but did not inhibit the growth of the E. Aerogenes, S. dysentriae and S. thypi. The ethyl acetate extract showed the highest antibacterial activity against P. aeruginosa, E. Coli, B. Subtilis and S. aureus, followed by chloroform, buthanol, and hexane extract, respectively. The ethyl acetate extract possed phenolic, condensed tannin, flavonoids, saponins and terpenoids. Based on the MIC and the equivalent value of ethyl acetate extract compared with that ampicillin used, the antibacterial activity of ethyl acetate extract was lower than with that of the ampicillin used.
Effect of Boiling on the Cytotoxic and Antioxidant Properties of Aqueous Fruit Extract of Desert Date, Balanites aegyptiaca (L) Delile
I Amadou, GW Le, YH Shi
Tropical Journal of Pharmaceutical Research , 2012,
Abstract: Purpose: To evaluate the effect of boiling on in vitro bioactivities potency of Balanites aegyptiaca L. Delile (desert date) aqueous extract, a juice used traditionally for cooking ready-to-eat millet flour paste. Methods: Desert date fruits (1.5 kg) were soaked in water (1:2, fruit: water) for 24 h and sieved. The extract was divided into two parts - fresh extract (Fext) and boiled extract (Bext) which was obtained by boiling a portion of Fext for 10 min. The extracts were tested against the stomach cancer cell line SGC7901 and for antioxidant activity by 1,1-diphenyl-2-icrylhydrazyl DPPH, hydroxyl radical and ferric reducing power methods. Results: Both fresh extract (Fext) and boiled extract (Bext) exhibited pronounced antioxidant activity with DPPH values of 88.2 and 97.0 %, respectively, at hydroxyl radical concentration of 5 mg/ml. The extract contained a significant amount of vitamin C (42.3 and 38.9 mg/100 g for Fext and Bext, respectively). Boiling had significant effect (p < 0.01) on its antioxidant activity and also on its cytotoxic effect (56 % and 44 % dead cells respectively for Bext and Fext at respectively, at a concentration of 200 μg/ml). Conclusion: It is concluded that B. aegyptiaca aqueous extracts have remarkable cytotoxic activity against stomach cancer cell SGC7901.
Developmental genetic analysis of fruit shape traits under different environmental conditions in sponge gourd (Luffa cylindrical (L) Roem. Violales, Cucurbitaceae)
Zhang, Sheng;Hu, Jin;Xu, Shengchun;
Genetics and Molecular Biology , 2008, DOI: 10.1590/S1415-47572008000400017
Abstract: analysis of genetic main effects and genotype × environment (ge) interaction effects for the fruit shape traits fruit length and fruit circumference in the sponge gourd (luffa cylindrical (l) roem. violales, cucurbitaceae) was conducted for diallel cross data from two planting seasons. a genetic model including fruit direct effects and maternal effects and unconditional and conditional variances analysis was used to evaluate the development of the fruit at four maturation stages. the variance analysis results indicated that fruit length and circumference were simultaneously affected by fruit direct genetic effects and maternal effects as well as ge interaction effects. fruit direct genetic effects were relatively more important for both fruit shape traits during the whole developmental period. gene activation was mostly due to additive effects at the first maturation stage and dominance effects were mainly active during the other three stages. the fruit shape trait correlation coefficients due to different genetic effects and the phenotypic correlation coefficients varied significantly for the various maturation stages. the results indicate that it is relatively easy to improve the two fruit shape traits for market purposes by carefully selecting the parents at the first maturation stage 3 days after flowering instead of at fruit economic maturation.
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