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121.
The galloylated cyanogenic glucosides based on prunasin (1-7), gallotannins (8-14), ellagitannins (15-17), ellagic acid derivatives (18, 19) and gallic acid (20) isolated from the leaves of Phyllagathis rotundifolia (Melastomataceae) were investigated for their neuroprotective activity against hydrogen peroxide (H2O2)-induced oxidative damage in NG108-15 hybridoma cell line. Among these compounds, the gallotannins and ellagitannins exhibited remarkable neuroprotective activities against oxidative damage in vitro as compared to galloylated cyanogenic glucosides and ellagic acid derivatives in a dose-dependent manner. They could be explored further as potential natural neuroprotectors in various remedies of neurodegenerative diseases. 相似文献
122.
Makita N Kosugi Y Dannoura M Takanashi S Niiyama K Kassim AR Nik AR 《Tree physiology》2012,32(3):303-312
The root systems of forest trees are composed of different diameters and heterogeneous physiological traits. However, the pattern of root respiration rates from finer and coarser roots across various tropical species remains unknown. To clarify how respiration is related to the morphological traits of roots, we evaluated specific root respiration and its relationships to mean root diameter (D) of various diameter and root tissue density (RTD; root mass per unit root volume; gcm(-3)) and specific root length (SRL; root length per unit root mass; mg(-1)) of the fine roots among and within 14 trees of 13 species from a primary tropical rainforest in the Pasoh Forest Reserve in Peninsular Malaysia. Coarse root (2-269mm) respiration rates increased with decreasing D, resulting in significant relationships between root respiration and diameter across species. A model based on a radial gradient of respiration rates of coarse roots simulated the exponential decrease in respiration with diameter. The respiration rate of fine roots (<2mm) was much higher and more variable than those of larger diameter roots. For fine roots, the mean respiration rates for each species increased with decreasing D. The respiration rates of fine roots declined markedly with increasing RTD and increased with increasing SRL, which explained a significant portion of the variation in the respiration among the 14 trees from 13 species examined. Our results indicate that coarse root respiration in tree species follows a basic relationship with D across species and that most of the variation in fine root respiration among species is explained by D, RTD and SRL. We found that the relationship between root respiration and morphological traits provides a quantitative basis for separating fine roots from coarse roots and that the pattern holds across different species. 相似文献
123.
Baloch Abdul Rasheed Franěk Roman Saito Taiju Pšenička Martin 《Fish physiology and biochemistry》2021,47(3):777-784
Fish Physiology and Biochemistry - Dead end (dnd) is a germ plasm-specific maternal RNA discovered in zebrafish and then in other vertebrates. Dnd protein is essential for migration and motility of... 相似文献
124.
This study is aimed at assessing the ability of metal-resistant yeast, Candida tropicalis, to uptake cadmium from the liquid medium. The minimum inhibitory concentration of Cd2+ against C. tropicalis was 2,800 mg L?1. The yeast also showed tolerance towards Zn2+ (3,100 mg L?1), Ni2+ (3,000 mg L?1), Hg2+ (2,400 mg L?1), Cu2+ (2,300 mg L?1), Cr6+ (2,000 mg L?1), and Pb2+ (1,200 mg L?1). The yeast isolate showed typical growth curves, but low specific rate of growth was observed in the presence of cadmium. The yeast isolate showed optimum growth at 30°C and pH 7. The metal processing ability of the isolate was determined in a medium containing 100 mg L?1 of Cd2+. C. tropicalis could decline Cd2+ 57%, 69%, and 80% from the medium after 48, 96, and 144 h, respectively. C. tropicalis was also able to remove Cd2+ 56% and 73% from the wastewater after 6 and 12 days, respectively. Cd produced an increase in glutathione (GSH) and non-protein thiol levels by 146.15% and 59.67% at 100 mg L?1 concentration, respectively. Metal tolerance and accumulation together with changes in the GSH status and non-protein thiols under Cd exposure were studied in C. tropicalis. 相似文献
125.
Three organic wastes (banana skin (BS), brewery spent grain (BSG), and spent mushroom compost (SMC)) were used for bioremediation of soil spiked with used engine oil to determine the potential of these organic wastes in enhancing biodegradation of used oil in soil. The rates of biodegradation of the oil were studied for a period of 84 days under laboratory conditions. Hydrocarbon-utilizing bacterial counts were high in all the organic waste-amended soil ranging between 10.2?×?106 and 80.5?×?106?CFU/g compared to unamended control soil throughout the 84 days of study. Oil-contaminated soil amended with BSG showed the highest reduction in total petroleum hydrocarbon with net loss of 26.76% in 84 days compared to other treatments. First-order kinetic model revealed that BSG was the best of the three organic wastes used with biodegradation rate constant of 0.3163 day?1 and half-life of 2.19 days. The results obtained demonstrated the potential of organic wastes for oil bioremediation in the order BSG?>?BS?>?SMC. 相似文献
126.
Sang-Mo Kang Muhammad Hamayun Gil-Jae Joo Abdul Latif Khan Yoon-Ha Kim Sang-Kuk Kim Hyung-Jin Jeong In-Jung Lee 《European Journal of Soil Biology》2010,46(3-4):264-268
Plant growth promoting rhizobacteria (PGPR) has been a focus of research for its potential as an eco-friendly alternative to chemical fertilizers in the agriculture industry. In current study, the effect of culture suspension (CS) of a novel gibberellins (GAs) producing bacterial strain Burkholderia sp. KCTC 11096BP, was observed on shoot length, shoot fresh and dry biomass, root fresh and dry biomass, chlorophyll contents, endogenous bioactive GAs (GA1 and GA4) and their immediate precursors, abscisic acid (ABA), soluble sugar contents and crude protein contents of cucumber (Cucumis sativus L.). We found that growth attributes of cucumber were significantly promoted by the application of CS of Burkholderia sp. KCTC 11096BP. The quantity of GA1 and GA4 and their immediate precursors GA20 and GA9 respectively, were also significantly promoted as compared to their respective controls. Contrary to GAs, the quantity of endogenous free ABA in cucumber leaves was much lower in bacterial CS treated plants. Soluble sugar contents and crude protein contents of cucumber leaves were also significantly higher in bacterial CS treatments as compared to control. It was concluded that Burkholderia sp. KCTC 11096BP can be used as an eco-friendly bio-fertilizer in our farming systems. 相似文献
127.
In this study growth and yield response of wheat crop to phosphobacterium inoculum was observed under sandy loam conditions.
The investigations were carried out at field experiment. The experiment was laid out in Randomized Complete Block Design.
The treatments were; 120-0-0 NPK kg/ha−1 (T
1), 120-50-0 kg/ha−1 (T
2), 120-100-0 NPK kg/ha−1 (T
3), T
1 + Phosphobacterium inoculum (T
4), T
2 + Phosphobacterium inoculum (T
5) and T
3 + Phosphobacterium inoculum (T
6).The results showed that bacterial strain (Pseudomonas spp.) was able to effect on yield and its attributes in wheat crop. The crop showed significant positive results. The inoculation
significantly stimulates the germination count (m−2), number of tillers and spikes (m−2), 1000 grains weight (g) and grain yield (kg/ha−1). We suggest that application of 120-100-0 kg/ha−1 NPK along with coating of seed with phosphobacterium (Pseudomonas spp.) all the way through inoculation is a better practice to reduce the exploit of phosphatic fertilizers which are much
costly. 相似文献
128.
Lim Chaw Jiang Dzolkhifli OmarMohd Basyaruddin Abdul Rahman Abu Bakar Salleh Raja Noor Zaliha Raja Abdul Rahman Ahmad Selamat 《Pesticide biochemistry and physiology》2012,102(1):19-29
This article describes the development of environmentally friendly nano-emulsion system for water-soluble herbicide application. Pseudoternary phase diagrams were established in the emulsion system of fatty acid methyl esters (FAMEs)/alkylpolyglucosides (APG) and/or 3-(3-hydroxypropyl)-heptamethyltrisiloxane (organosilicone)/water encompassed with 41% (w/w) glyphosate isopropylamine (IPA) as herbicide active. Pre-formulations were selected from isotropic (L) region in the phase diagrams and their emulsion system characteristics were determined. The microemulsion systems were chosen and then dispersed into water using low-energy stirring method (200 rpm for 5 min). Oil-in-water (O/W) nano-emulsions were formed with particle sizes of diameter less than 200 nm. The nano-emulsion systems showed significantly lower surface tension than a commercial formulation (Roundup®). In the biological application study, treatments of nano-emulsion formulations and Roundup® were applied on narrow-leaved weed Eleusine indica. Multiple doses of glyphosate IPA of the treatments were applied for the construction of dose-response curves for determination of effective dose (ED50). The nano-emulsion formulation showed lower ED50 was 0.40 kg a.e./ha in controlling the weed than Roundup® was 0.48 kg a.e./ha. This finding suggested that the possibility of using nano-emulsion system to increase penetration and uptake of glyphosate IPA. 相似文献
129.
Background
Global climate warming can affect functioning of crops and plants in the natural environment. In order to study the effects of global warming, a method for applying a controlled heating treatment to plant canopies in the open field or in the greenhouse is needed that can accept either square wave application of elevated temperature or a complex prescribed diurnal or seasonal temperature regime. The current options are limited in their accuracy, precision, reliability, mobility or cost and scalability. 相似文献130.
Salehzadeh A Jabbar A Jennens L Ley SV Annadurai RS Adams R Strang RH 《Pest management science》2002,58(3):268-276
A range of cultured cells of invertebrate and vertebrate origin was grown in the presence of a number of phytochemical pesticides to test the effect of the latter on cell proliferation. The main observation was that azadirachtin was a potent inhibitor of insect cell replication, with an EC50 of 1.5 x 10(10) M against Spodoptera cells and of 6.3 x 10(9) M against Aedes albopictus cells, whilst affecting mammalian cells only at high concentrations (> 10(-4) M). As expected, the other phytochemical pesticides, except for rotenone, had little effect on the growth of the cultured cells. Rotenone was highly effective in inhibiting the growth of insect cells (EC50:10(-8) M) but slightly less toxic towards mammalian cells (EC50:2 x 10(-7) M). Neem terpenoids other than azadirachtin and those very similar in structure significantly inhibited growth of the cell cultures, but to a lesser degree. The major neem seed terpenoids, nimbin and salannin, for example, inhibited insect cell growth by 23% and 15%, respectively. 相似文献