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91.
Farhan Ahmad Gui-Ying Yang Shi-You Liang Qi-Huan Zhou Hassan Ahmed Gaal Jian-Chu Mo 《Insect Science》2021,28(6):1512-1529
Fungus-growing termites are among the most successful herbivorous animals and improve crop productivity and soil fertility. A range of symbiotic organisms can be found inside their nests. However, interactions of termites with these symbionts are poorly understood. This review provides detailed information on the role of multipartite symbioses (between termitophiles, termites, fungi, and bacteria) in fungus-growing termites for lignocellulose degradation. The specific functions of each component in the symbiotic system are also discussed. Based on previous studies, we argue that the enzymatic contribution from the host, fungus, and bacteria greatly facilitates the decomposition of complex polysaccharide plant materials. The host–termitophile interaction protects the termite nest from natural enemies and maintains the stability of the microenvironment inside the colony. 相似文献
92.
A simple procedure has been developed for sequencing long (40-kb) DNA fragments by the dideoxy method. The fragment is cloned in the sequencing cosmid pAA113X by in vitro packaging, and subdivided by a series of overlapping IS1-promoted deletions. The deletions are isolated by positive selection for galactose resistance. Plasmids from several thousand galactose-resistant colonies are fractionated on an agarose gel, and DNA from each fraction is restricted with enzymes (such as SphI and SalI) to shorten each deletion from the opposite end. As a result, a series of short overlapping segments, spread across the entire length of the fragment, are fused to IS1. The plasmids are extracted by a rapid method, arranged according to size, and used for supercoil sequencing with an IS1 primer. Sequences of IS1-promoted deletions contain extensive overlaps that are connected further by restriction enzyme-generated deletions to give the complete 40-kb sequence. 相似文献
93.
Tajbiha E. Mowla Sumyya Zahan Saad Ahmed Sami S.M. Naim Uddin Minhajur Rahman 《Saudi Journal of Biological Sciences》2022,29(5):3791-3805
Multidrug-resistant bacterial infections, helminthiasis, thrombosis, anxiety and insomnia are some of the major global health concerns. Vigna mungo (L.) Hepper (VM) has been used traditionally to treat microbial infection, helminthic disorder, schizophrenia, memory loss, and blood circulatory problem. This research aims to discover antibacterial, anthelmintic, thrombolytic and neuropharmacological effects of the methanol extract of Vigna mungo seeds (MESVM), and also in-silico prediction of relevant lead compounds by molecular docking and ADME/T analysis. The crude extracts and subsequent fractions of MESVM were investigated for antibacterial activity by disc diffusion method, anthelmintic activity by paralysis and death test on earthworms, and thrombolytic activity by in vitro blood clot dissolution test. Open-field test and elevated plus maze test were performed for evaluating anxiolytic activity of the extracts. Using molecular docking, ligand poses of selected VM seeds’ phytoconstituents were predicted targeting tubulin, GlcN-6-P synthase, and human tissue plasminogen activator proteins for anthelmintic, antibacterial, and thrombolytic activity, respectively. In the antibacterial activity test, the MESVM at 10000 μg/mL concentration created highest and significant (P < 0.001) zone of inhibition against Staphylococcus aureus (15.42 mm) and Escherichia coli (12 mm) compared with tetracycline. The MESVM exhibited remarkable anthelmintic activity at 50 mg/mL concentration with 35.4 min paralysis time, 75.2 min death time and were closer to the durations of standard drug albendazole. No test extract showed anxiolytic activity. In thrombolytic activity test, all concentrations of MESVM produced clot lytic activity with high significance (P < 0.001) in comparison with the blank. In docking, 2′-hydroxygenistein, cyclokievitone hydrate, and aureol displayed maximum affinity to the target proteins for anthelmintic, antibacterial, and thrombolytic activity, respectively. This research revealed that the MESVM demonstrated potential anthelmintic, antibacterial and thrombolytic effects that confirmed the folkloric uses of VM and the found relevant lead compounds might be further optimized in future drug development. 相似文献
94.
Syed Mohsin Bukhari Huda Ahmed Alghamdi Khalil Ur Rehman Shahla Andleeb Shahbaz Ahmad Nimra Khalid 《Saudi Journal of Biological Sciences》2022,29(3):1781-1788
Pheasant reintroduction and conservation efforts have been in place in Pakistan since the 1980 s, yet there is still a scarcity of data on pheasant microbiome and zoonosis. Instead of growing vast numbers of bacteria in the laboratory, to investigate the fecal microbiome, pheasants (green and ring neck pheasant) were analyzed using 16S rRNA metagenomics and using IonS5TMXL sequencing from two flocks more than 10 birds. Operational taxonomic unit (OTU) cluster analysis and phylogenetic tree analysis was performed using Mothur software against the SSUrRNA database of SILVA and the MUSCLE (Version 3.8.31) software. Results of the analysis showed that firmicutes were the most abundant phylum among the top ten phyla, in both pheasant species, followed by other phyla such as actinobacteria and proteobacteria in ring necked pheasant and bacteroidetes in green necked pheasant. Bacillus was the most relatively abundant genus in both pheasants followed by Oceanobacillus and Teribacillus for ring necked pheasant and Lactobacillus for green necked pheasant. Because of their well-known beneficial characteristics, these genus warrants special attention. Bird droppings comprise germs from the urinary system, gut, and reproductive sites, making it difficult to research each anatomical site at the same time. We conclude that metagenomic analysis and classification provides baseline information of the pheasant fecal microbiome that plays a role in disease and health. 相似文献
95.
Esraa E. Ammar Ahmed A.A. Aioub Ahmed E. Elesawy Ali M. Karkour Moustafa S. Mouhamed Aliaa A. Amer Nouran A. EL-Shershaby 《Saudi Journal of Biological Sciences》2022,29(5):3083-3096
Bio-fertilization is a sustainable agricultural practice that includes using bio-fertilizers to increase soil nutrient content resulting in higher productivity. Soil micro-flora has been exposed to improve soil fertility and increase biomass productivity and identified as a correct environmentally friendly bio-based fertilizer for pollution-free agricultural applies. The majority of cyanobacteria can fix nitrogen from the atmosphere and several species including Anabaena sp., Nostoc sp., and Oscillatoria angustissima is known to be effective cyanobacterial based bio fertilizers. Acutodesmus dimorphus, Spirulina platensis Chlorella vulgaris, Scenedesmus dimorphus, Anabaena azolla, and Nostoc sp. are some of the green microalgae and cyanobacteria species that have been successfully used as bio fertilizers to boost crop growth. Also, Chlorella vulgaris is one of the most commonly used microalgae in bio fertilizer studies. The addition of seaweed species that are Sargassum sp. and Gracilaria verrucosa leads to chemical changes as a soil fertility indicator on clay and sandy soils, and the addition of seaweed conditioner to soil can improve its organic content, return pH to normal, and reduce C/N ratio in both sandy and clay soil. This review provides an effective approach to increase soil fertility via environmentally friendly bio-based fertilizer using micro and macro algae. Instead of the usage of inorganic and organic fertilizers that have polluted impacts to soil as aggregation of heavy metals, in addition to there their human carcinogenic effects. 相似文献
96.
Syeda Mehpara Farhat Aamra Mahboob Ghazala Iqbal Touqeer Ahmed 《Biological trace element research》2017,177(1):115-121
Aluminum is associated with etiology of many neurodegenerative diseases specially Alzheimer’s disease. Chronic exposure to aluminum via drinking water results in aluminum deposition in the brain that leads to cognitive deficits. The study aimed to determine the effects of aluminum on cholinergic biomarkers, i.e., acetylcholine level, free choline level, and choline acetyltransferase gene expression, and how cholinergic deficit affects novel object recognition and sociability in mice. Mice were treated with AlCl3 (250 mg/kg). Acetylcholine level, free choline level, and choline acetyltransferase gene expression were determined in cortex, hippocampus, and amygdala. The mice were subjected to behavior tests (novel object recognition and social novelty preference) to assess memory deficits. The acetylcholine level in cortex and hippocampus was significantly reduced in aluminum-treated animals, as compared to cortex and hippocampus of control animals. Acetylcholine level in amygdala of aluminum-treated animals remained unchanged. Free choline level in all the three brain parts was found unaltered in aluminum-treated mice. The novel object recognition memory was severely impaired in aluminum-treated mice, as compared to the control group. Similarly, animals treated with aluminum showed reduced sociability compared to the control mice group. Our study demonstrates that aluminum exposure via drinking water causes reduced acetylcholine synthesis in spite of normal free choline availability. This deficit is caused by reduced recycling of acetylcholine due to lower choline acetyltransferase level. This cholinergic hypofunction leads to cognitive and memory deficits. Moreover, hippocampus is the most affected brain part after aluminum intoxication. 相似文献
97.
Effect of vegetation on density thresholds of adult desert locust gregarization from survey data in Mauritania 总被引:1,自引:0,他引:1
Sory Cisse Saïd Ghaout Ahmed Mazih Mohamed Abdallahi Ould Babah Ebbe Ahmed Salem Benahi Cyril Piou 《Entomologia Experimentalis et Applicata》2013,149(2):159-165
In the desert locust, Schistocerca gregaria (Forskål) (Orthoptera: Acrididae), the threshold density inducing the gregarization phenomenon has never been determined under natural conditions. The influence of environmental factors on this phenomenon has been studied mostly in controlled environments. Based on data collected during several years by the survey teams of the National Center for Locust Control in Mauritania, we analyzed the influence of locust density, vegetation cover, and vegetation status on the probability of observing gregarious locusts. We assumed that a probability to observe gregarious locusts of 0.5 corresponded to the density threshold of gregarization. The results showed in detail the change in the threshold of gregarization according to the cover and status of the vegetation. Low cover and dry vegetation led to a low density threshold of gregarization probably due to high probability of individuals to touch each other. Dense and green vegetation favored a high threshold of gregarization probably due to a dispersion of the individuals and a low probability of individual encounters. These findings should help the management of locusts and decision making during control operations. 相似文献
98.
印度地鼠的性成熟和窝仔数 总被引:1,自引:0,他引:1
Rubina ARSHAD 《动物学报》2004,50(5):723-729
为有效地进行有害脊椎动物的控制 ,研究了栖息于巴基斯坦Punjab中部的 348只印度地鼠的繁殖模式。在所捕捉到的 10 7雄鼠和 2 4 1只雌鼠中 ,分别有 75只和 179只是性成熟的个体。性比偏雌。使用被捕个体标本的体重和体长作为指标 ,发现最小的性成熟的雄性个体体重为 70 - 89g ,体长 13 1- 14 0cm ;一窝仔里面的平均胚胎数为 2 74± 0 15 (范围 ,1- 5 ) ,而平均胎斑数为 4 2 9± 0 19(1- 11) .体重似乎对窝仔数有显著影响 ,而体长和估计的年龄对窝仔数没影响。当老鼠繁殖不活跃和不繁殖时 ,控制害兽最有效 相似文献
99.
Stamatia Bellou Mohammed N. Baeshen Ahmed M. Elazzazy Dimitra Aggeli Fotoon Sayegh George Aggelis 《Biotechnology advances》2014
In the last few years, there has been an intense interest in using microalgal lipids in food, chemical and pharmaceutical industries and cosmetology, while a noteworthy research has been performed focusing on all aspects of microalgal lipid production. This includes basic research on the pathways of solar energy conversion and on lipid biosynthesis and catabolism, and applied research dealing with the various biological and technical bottlenecks of the lipid production process. In here, we review the current knowledge in microalgal lipids with respect to their metabolism and various biotechnological applications, and we discuss potential future perspectives. 相似文献
100.
Attached media reactors are used for enhancement of wastewater treatment processes including anaerobic condition. Selection of a suitable biofilm carrier is a compelling method to improve anaerobic digestion systems. This study investigates the performance of four fibrous biofilms installed in batch biogas reactors for treatment of cow manure. BioCords HS1, HS2, LS1, and LS2 are manufactured by Bishop Water Technologies, ON, Canada. Effluents and attached growth media were analyzed after batch experiment; methane production, methane yield, transfer efficiencies, organic and solid removal efficiencies, pH, and attached volatile suspended solid (VSS) were measured; VSS attached to biofilms mainly correlated with the specific surface area of each biofilm. Additionally, SEM (scanning electron microscopy) was used for further understanding of biofilm formation process for BioCords and the dissimilarity in their performance. The results indicated that BioCord LS2 had positive impact on achieving higher methane production and removal efficiencies compared to other support media utilized in batch reactors. It was also demonstrated from the experiment that BioCord LS2 potentially could generate higher methane production than conventional batch bioreactor. 相似文献