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101.
The possibility to cultivate Lactococcus lactis in aqueous polymer two-phase system has been investigated. The phase system was made up of poly(ethylene imine) and (hydroxyethyl) cellulose. Long lag phases were needed for the microorganism to adapt to the polymer rich media. Cells favoured the (hydroxyethyl)cellulose rich top phase or they accumulated at the interface, while lactic acid showed affinity for the poly(ethylene imine) rich phase.Abbreviations PEG
poly(ethylene glycol)
- PEI
poly(ethylene imine)
- HEC
(hydroxyethyl)cellulose 相似文献
102.
Some chimpanzees use 2 types of tools to extract underground termites for consumption. Chimpanzees insert thin, flexible probes into tunnels or holes in termite mounds (fishing), and sometimes use stouter, rigid sticks to first puncture the holes and also possibly to fish. Many puncturing sticks have distinctive “brushed” ends. Researchers have hypothesized that chimpanzees create the brushed ends intentionally to increase their affixibility to biting termites (Sugiyama, 1985). The results of our archaeological analysis of a large collection of puncturing sticks used by Central African chimpanzees falsifies this hypothesis, and instead agrees with the recent behavioral observations of Sanz et al. (2004; cf. Bermejo and Illera, 1999) that brushing is a coincidental result of procuring sticks from vegetation sources. The results highlight the positive contribution of an archaeological approach to problems in chimpanzee material culture and emphasize to primatologists the value of curating artifacts. 相似文献
103.
Dr. Shehla Akbar Prof. Dr. Saiqa Ishtiaq Assoc. Prof. Dr. Fadia S. Youssef Assoc. Prof. Dr. Sameh S. Elhady Assoc. Prof. Dr. Amal K. Belaid Prof. Dr. Mohamed L. Ashour 《化学与生物多样性》2023,20(9):e202300349
The current study aimed to evaluate the anti-inflammatory activity of Dicliptera bupleuroides Nees aerial parts methanol extract and its different fractions namely hexane, chloroform, ethyl acetate and butanol in vitro using cyclooxygenase inhibitory assay (COX-2). In vivo anti-inflammatory evaluation was performed using carrageenan and formalin induced inflammation in rat models followed by molecular docking. High performance liquid chromatography (HPLC) and gas chromatography coupled with mass chromatography (GC/MS) analyses were used for chemical analyses of the tested samples. The tested samples showed significant inhibition in COX-2 inhibitory assay where methanol extract (DBM) showed the highest inhibitory potential at 100 μg/mL estimated by 67.86 %. At a dose of 400 mg/kg, all of the examined samples showed pronounced results in carrageenan induced acute inflammation in rat model at 4th h interval with DBM showed the highest efficiency displaying 65.32 % inhibition as compared to the untreated rats. Formalin model was employed for seven days and DBM exhibited 65.33 % and 69.39 % inhibition at 200 and 400 mg/kg, respectively approaching that of the standard on the 7th day. HPLC revealed the presence of caffeic acid, gallic acid and sinapic acid, quercetin and myricetin in DBM. GC/MS analysis of its hexane fraction revealed the presence of 16 compounds belonging mainly to fatty acids and sterols that account for 85.26 % of the total detected compounds. Molecular docking showed that hexadecanoic acid followed by decanedioic acid and isopropyl myristate showed the best fitting within cyclooxygenase-II (COX-II) while nonacosane followed by hexatriacontane and isopropyl myristate revealed the most pronounced fitting within the 5-lipoxygenase (5-LOX) active sites. Absorption, metabolism, distribution and excretion and toxicity prediction (ADMET/ TOPKAT) concluded that most of the detected compounds showed reasonable pharmacokinetic, pharmacodynamic and toxicity properties that could be further modified to be more suitable for incorporation in pharmaceutical dosage forms combating inflammation and its undesirable consequences. 相似文献
104.
105.
B. J. King 《Human Evolution》1986,1(4):361-372
One of the two major theories regarding the evolution of intelligence in primates is that feeding strategies determine mental
development. Evidence for this theory is reviewed and related to extractive foraging, which is the act of locating and/or
processing embedded foods such as underground roots and insects or hard-shelled nuts and fruits. It is shown that, although
only cebus monkeys and chimpanzees in the wild use tools in extractive foraging, many other species of mammals (including
primates) and birds are capable of extracting embedded foods without tools. Extractive foraging by primates is compared to
extractive foraging by other mammals and birds to assess whether: 1) extractive foraging involves cognition, and 2) extractive
foraging by primates is unique in a way that may mean it played a role in the development of intelligence among primates.
This comparison reveals that some acts of extractive foraging by nonprimates are equally sophisticated as those of primates.
It is suggested that extractive foraging played no significant role in the evolution of primate intelligence. Hypotheses for
testing precise differences in extractive foraging ability across taxa are offered, and the roles of olfactory cues, manual
dexterity, and strength in extractive foraging are evaluated.
In conclusion, the hominization process is briefly reviewed in relation to foraging behavior. A ?package? of traits that,
in combination, is unique to hominids is discussed: tool-aided extractive foraging, division of labor by sex with food exchange,
and feeding of juveniles. 相似文献
106.
Müge Gökdere 《Preparative biochemistry & biotechnology》2013,43(1):80-89
Gibberelic acid fermentation using extractive methods was carried out in the presence of corn oil and Alamine 336. Gibberella fujikuroi fungus (NRRL 2278) was used to produce gibberellic acid. Oleyl alcohol was a diluting agent for Alamine 336. The effects of oleyl alcohol (100%, v/v), corn oil (5–25%, v/v), the concentration of Alamine 336 in oleyl alcohol, and feeding air were examined in this study. According to the results, oleyl alcohol was not effective on the production. On the other hand, oleyl alcohol solutions containing 15–30% (v/v) Alamine 336 showed effects as a toxic substance. In order to reduce solvent toxicity, corn oil was used. Addition of corn oil increased the concentration of gibberellic acid 1.3-fold compared to the control. Then the effects of immobilization and co-immobilization on extractive gibberelic acid fermentation were investigated. The highest total gibberellic acid concentration of 158.9 mg/L was produced with immobilized cells and feeding air by using extractive fermentation. The yield of gibberellic acid increased about 2.6-fold compared with the shake-flask fermentation (60.5 mg/L) without organic solutions. 相似文献
107.
Quentin Gallot Thibaud Gruber 《Ethology : formerly Zeitschrift fur Tierpsychologie》2019,125(10):755-758
Here, we report an observation of a zoo‐housed common raven (Corvus corax) modifying and using a raven feather as a tool to access the food cache of her partner. We believe this record is of importance, as it represents one of the first cases of untrained common ravens spontaneously using and modifying a tool, and a rare example of a non‐human animal manufacturing a tool from a body part. This anecdotal observation suggests that tool use and tool modification may be present in the common raven behavioral repertoire in the foraging context; nevertheless, further investigations are needed to assess this possibility in more controlled settings as well as in the wild. 相似文献
108.
109.
New Caledonian crows are renowned for their unusually sophisticated tool behaviour. Despite decades of fieldwork, however, very little is known about how they make and use their foraging tools in the wild, which is largely owing to the difficulties in observing these shy forest birds. To obtain first estimates of activity budgets, as well as close-up observations of tool-assisted foraging, we equipped 19 wild crows with self-developed miniature video cameras, yielding more than 10 h of analysable video footage for 10 subjects. While only four crows used tools during recording sessions, they did so extensively: across all 10 birds, we conservatively estimate that tool-related behaviour occurred in 3% of total observation time, and accounted for 19% of all foraging behaviour. Our video-loggers provided first footage of crows manufacturing, and using, one of their most complex tool types—hooked stick tools—under completely natural foraging conditions. We recorded manufacture from live branches of paperbark (Melaleuca sp.) and another tree species (thought to be Acacia spirorbis), and deployment of tools in a range of contexts, including on the forest floor. Taken together, our video recordings reveal an ‘expanded’ foraging niche for hooked stick tools, and highlight more generally how crows routinely switch between tool- and bill-assisted foraging. 相似文献
110.
Captive tufted capuchins are proficient at both tool use and manufacture. However, their capacity to comprehend cause-effect relationships as they relate to tool use is a subject of debate. An ability to conceptualize task requirements in assessing the appropriateness of potential tools would be essential to efficient tool use in the wild. Observations of tool use among free-ranging populations of Cebus are extremely limited, and the importance of this behavior to capuchin feeding ecology is unclear. I tested tufted capuchins' ability to conceive solutions to a probing task in a naturalistic captive setting. Three out of 5 participants demonstrated an ability to consistently make and use tools selected from a wide variety of natural materials within a forest exhibit. Over 98% (N = 140) of the tools that they modified enabled them to successfully acquire food rewards. It is likely that wild Cebus apella shares this ability, and that tool use occurs under a highly specific set of natural conditions. 相似文献