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81.
Mohamed Z. M. Salem Mohamed Z. Zayed Hayssam M. Ali Mamoun S. M. Abd El-Kareem 《Journal of Wood Science》2016,62(6):548-561
In the present work, for the first time, the chemical components of essential oils (EOs) and extracts from wood branch (WB) resulted from the tree pruning wastes of Schinus molle L. grown in Egypt were evaluated for their antioxidant and antibacterial activities. EOs, methanol (ME), dichloromethane (DCME) and water (WE) extracts as antioxidant and antibacterial activities were measured. Total phenolic and flavonoid contents as well as analysis of extracts by gas chromatography–mass spectrometry (GC–MS) were reported. The major components in EOs were α-elemol, β-pinene, and α-phellandrene, in ME were 6-(4-chlorophenyl)-3-cyano-4-(N-benzylpiperazino)-2H-pyran-2-one, and 2-naphthalene methanol, decahydro-α,α,4a-trimethyl-8-methylene, in DCME were 12-methyl-E,E-3,13-octadecadien-1-ol, and 1,2-benzenedicarboxylic acid, dioctyl ester, and in WE were β-eudesmol, and (Z,Z,Z)-9,12,15-octadecatrienoic acid, 2,3-dihydroxypropyl ester. The highest total antioxidant activity was found with EOs (90 ± 1.23 %) and WE (86.30 ± 1.40 %). The lowest IC50 values of 13.11 ± 3.00, and 12.66 ± 2.15 μg/mL were found with WE and EOs, respectively. EOs and WE were observed to have good antibacterial activity against Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Escherichia coli, Sarcina lutea, Pseudomonas aeruginosa, and Micrococcus luteus. In conclusion, the Schinus molle L. WB EOs and extracts might, indeed, be used as a potential source for pharmaceutical or food industries. 相似文献
82.
Summary Four species of fast growing annual plant viz.Hibiscus sabdariffa, Crotalaria juncea, Tephrosia candida andHibiscus cannabinus and a variety of reed, Neyraudia reynaudiana were evaluated in the laboratory for their pulp and paper making properties. Data on proximate chemical analysis of raw materials, unbleached and bleached pulp properties, morphological properties of fibres and physical strength properties of paper sheets were evaluated. The unbleached pulp yields were 44.90–53.20% with all the five plant materials, while bleached pulp yields varied from 39.80–50.60%. The average fibre lengths and diameters of the unbleached pulp obtained from the five plant species were within the range of 0.75 mm–2.15 mm and 20–22 pun respectively. Paper hand sheets, made with bleached pulps (45° SR) obtained from the five plant species, gave burst indices 2.75–3.92 kPa m2/g, tear indices 3.73–9.61 m N m2/g and tensile indices 37.27–47.81 N mg–1, indicating adequate strength properties for writing and printing type of paper.The authors thank Director, Regional Research Laboratory (CSIR), Jorhat, India, for his kind permission to publish this paper. The authors also wish to thank B. N. Tosh, JPF for his assistance. 相似文献
83.
Green stem cuttings, obtained from 2-year old managed stockplants, with 30, 50 or 100% leaf area were rooted in a non-mist propagator following treatment with 0, 0.2, 0.4 or 0.8% IBA solution. The rooted cuttings were transferred to polythene pots and grown in a nursery for 12 weeks. Rooting percentages of IBA treated cuttings did not significantly differ from those of control cuttings. Likewise leaf area did not significantly influence the percentage of cuttings that rooted. The effects of leaf area and/or IBA treatment in the propagation unit were manifested on the growth of rooted cuttings in polythene pots. Number of roots increased with the increase in IBA concentration and this response was enhanced by increasing leaf area. Root biomass increased with the increase in leaf area even in the control cuttings. Root development was highly influenced by the leaf area and IBA, and hence the growth of rooted cuttings. Cuttings treated with 0.2 or 0.4% IBA at 100% leaf area yielded the best performing rooted cuttings. 相似文献
84.
Pseudomonas solanacearum (Smith) was consistently isolated from the wilted plants of Casuarina equisetifolia. The isolate gave positive reaction to oxidase, catalase and gas production from nitrate and negative reaction for arginine dihydrolase and acid was produced from various carbohydrates. Wilt produced on tomato, egg plant and capsicum indicated that the pathogen belongs to Race I and Biovar III of P. solanacearum which is a new record from India. 相似文献
85.
This paper explores the influence over time of past policies on people’s attitudes towards the use of forestland in Bangladesh.
The discourses of the attitudes of people were captured from the observed social tradition towards forest resources. Forests
were reserved systematically and solely through the Forest Department. The conservation processes were not participatory,
and rights and tenure were strictly controlled. People were socially excluded and alienated from the forest, and the socio-political
factors stimulated negative attitudes among people. Forests were considered to be government property, and therefore managing
forests was the responsibility of the government. People only used forest resources to meet their own requirements, either
with formal permission or illegally. This situation continued even after the independence of Bangladesh in 1971. As a result,
the forests of Bangladesh have been degraded heavily in recent decades. 相似文献
86.
Micromechanics of wood subjected to axial tension 总被引:5,自引:0,他引:5
Parviz Navi Pramod K. Rastogi Valérie Gresse Ali Tolou 《Wood Science and Technology》1995,29(6):411-429
Summary The behaviour of a small group of wood fibers of Sitka spruce during tensile loading is investigated. The load-extension curves for both early and late wood fibers consist of three distinct segments. The first segment is almost a straight line, at some stage of loading a yield point is observed. Beyond this point the specimen becomes less stiff and undergoes a large, mainly irreversible deformation. As the load is increased further, the curve exhibits the third segment showed by a significant change in slope. These curves look different from those obtained on thick specimens. In this respect, the behaviour of a thin wood specimen subjected to cyclic type tensile loading along its longitudinal direction is also illustrated. Based on wood microstructure, a model is presented to interpret the evolution of the Young's modulus of a wood fiber during tensile loading. The model considers wood as an assembly of cylindrical fibers pasted together in a longitudinal direction. We have assumed the cell wall to comprise only an S2 layer made of a composite material consisting of a lignin and hemicellulose matrix reinforced by helical microfibrils along the fiber. Furthermore, it is assumed that the microfibril angle a in the S2 layer is not uniform along the fiber axis and matrix degradation occurs in the zones where the microfibril angles are bigger. The validity of this assumption is verified by using holographic interferometry to visualize the displacement field of the specimen's surface under tension.The work reported in this paper is supported by a grant from the Swiss National Science Foundation, and its support is gratefully acknowledged 相似文献
87.
Bracon instabilis Marshal is an ectoparasite attacking the larvae ofP. operculella in Egypt. According to available literatures, this is the first study onB. instabilis. The laboratory rearing of this parasite was undertaken on the third and fourth larval instars ofP. operculella and the method was mentioned in details. Certain aspects of the morphology of the immature and adult stages were given. The durations of the immature stages of the parasite were estimated at 15 and 25°C and 60±5% R.H. The total durations of the immature stages (from egg to adult) were 39.62 and 11.19 days at 15 and 25°C, respectively. 相似文献
88.
A new steroidal alkaloid, named antidysentericine, has been isolated from the seeds of Holarrhena antidysenterica and characterized as 3 beta-dimethylaminocon-5-enin-18-one (1). 相似文献
89.
Asgari Safdar Amir Hossein Sadeghi Ali Asghar 《Tropical animal health and production》2015,47(1):185-189
Tropical Animal Health and Production - This study was conducted to evaluate the male effect on the manifestation of estrus and feeding behavior of Afshari ewes during their breeding season. The... 相似文献
90.
Mohamed M’BAYE Guohua HUA Hamid Ali KHAN Liguo YANG 《The Journal of reproduction and development》2015,61(5):391-397
Inhibins are members of the TGFβ superfamily and act as suppressors
of follicle stimulating hormone (FSH) secretion from pituitary glands
via a negative feedback mechanism to regulate folliculogenesis. In
this study, the INHBB gene was knocked down by three
RNAi-Ready pSIREN-RetroQ-ZsGreen vector- mediated recombinant plasmids
to explore the effects of INHBB silencing on
granulosa cell (GC) cell cycle, apoptosis and steroid production
in vitro. Quantitative real-time polymerase chain
reaction, Western blot, flow cytometry and ELISA were performed to
evaluate the role of INHBB in the mouse GC cell
cycle, apoptosis and steroid production in vitro. The
results showed that the relative mRNA and protein expression of
INHBB in mouse GCs can be significantly reduced by
RNAi with pshRNA-B1, pshRNA-B2 and pshRNA-B3 plasmids, with pshRNA-B3
having the best knockdown efficiency. Downregulation of the expression
of INHBB significantly arrests cells in the G1 phase
of the cell cycle and increases the apoptosis rate in GCs. This was
further confirmed by downregulation of the protein expressions of
Cyclin D1, Cyclin E and Bcl2, while the protein expression of Bax was
upregulated. In addition, specific downregulation of
INHBB markedly decreased the concentration of
estradiol and progesterone, which was further validated by the
decrease in the mRNA levels of CYP19A1and
CYP11A1. These findings suggest that inhibin βB is
important in the regulation of apoptosis and cell cycle progression in
granulosa cells. Furthermore, the inhibin βB subunit has a role in the
regulation of steroid hormone biosynthesis. Evidence is accumulating
to support the concept that inhibin βB is physiologically essential
for early folliculogenesis in the mouse. 相似文献