Effects of Lactobacillus formosensis S215T and Lactobacillus buchneri on quality and in vitro ruminal biological activity of condensed tannins in sweet potato vines silage

2016 ◽  
Vol 121 (5) ◽  
pp. 1242-1253 ◽  
Author(s):  
M.C. Mangwe ◽  
K.T. Rangubhet ◽  
V. Mlambo ◽  
B. Yu ◽  
H.I. Chiang

Author(s):  
Khaoula Khelalfa ◽  
Rabah Arhab ◽  
Antonio Ignacio Martín-García ◽  
Nabila Zaabat ◽  
Alejandro Belanche

Condensed tannins are polyphenolic compounds which can exert beneficial effects in ruminants. They have the ability to bind proteins and decrease their degradation. They have also been reported to reduce methanogenesis and improve ruminants performances. The present work aimed to study the effect of purified condensed tannins from Acacia horrida extract on fermentation parameters, gas and methane production. In this context, seven substrates were selected: four Acacia species (Acacia pycnantha, Acacia dealbata, Acacia horrida and Acacia cyanophylla) and three plant by-products (date palm leaves, grenade peel and artichoke stems). Biological activity of tannins was evaluated by the incubation of the substrates in vitro with Polyethylene glycol (PEG). Tannins decreased concentration of all fermentation parameters (gas (p < 0.0001), methane (CH4) (p= 0.0983), ammonia (N-NH3) (p= 0.0382), Volatile Fatty Acids (VFA) (p= 0.0009), acetate (p <0.0001), propionate (p= 0.1024), butyrate (p= 0.0373), isobutyrate (p= 0.0046), valerate (p < 0.0001), isovalerate (p= 0.0032)). Substrates were also characterized by their content in main nutrients (dry matter (DM), organic matter (OM), ash, crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF) ,acid detergent lignin (ADL)) and in secondary metabolites (total phenols (TP), total tannins (TT) and condensed tannins (CT) ). All substrates presented high CP content except by-products (> 100 g/kg DM) and moderate cell-wall components. CT content was comprised between 120.5 and 680.4 g/kg DM in plants and between 23.1 and 170.4 g/kg DM in plant by-products. A. horrida presented the highest biological activity. Thus, their CT were extracted and purified on a sephadex LH-20 column. Purified tannins from A. horrida were incubated with two different forages alfalfa hay and barley straw at three different concentrations: 50, 100, 150 mg/g DM. Results showed that purified tannins from A. horrida had no effect on fermentation parameters (P > 0.05). The effects of A. horrida tannins may be strongly linked to their structure and their molecular weight more than to their concentration. For this reason, it is interesting that this work may be completed by physical characterization of these tannins.



1998 ◽  
Vol 6 (1) ◽  
pp. 175-181 ◽  
Author(s):  
A.V. Goodchild ◽  
F.J. El Haramein ◽  
A. Abd El Moneim ◽  
H.P.S. Makkar ◽  
P.C. Williams

Near infrared (NIR) spectroscopy calibrations for measures of tannins and nutritive value were made on a set of 40 hays and straws of Vicia and Lathyrus spp. by the modified partial least squares (MPLS) method and were evaluated by cross-validation. They successfully predicted, in the dry matter, 4.6–34.1 g kg−1 total phenolics with a cross-validation R2 of 0.95 and a SECV of 1.68 g kg−1, 1.3–23.1 g kg−1 total tannins ( R2 = 0.89, SECV = 1.84 g kg−1) and 0.5–30.3 g kg−1 condensed tannins ( R2 = 0.93, SECV = 2.34 g kg−1). In multiple regression and MPLS calibrations, a wavelength close to 2.144 μm was common to all measures of tannins, and was attributed to condensed tannins and its flavanoid precursors. The biological activity of tannins on rumen microbes, measured as a 0–6.9% effect on gas production with rumen liquor in vitro, was less precisely predicted by MPLS ( R2 = 0.49, SECV = 1.49%). The biological activity per gram of chemical tannins could not be predicted by NIR spectroscopy in the material studied. Acid detergent fibre, neutral detergent fibre, crude protein and gas production in vitro were predicted with R2 = 0.95 to 0.96 ( SECV = 18.2, 24.8, 10.1 g kg−1 or 7.2 mL g−1).



1963 ◽  
Vol 42 (2) ◽  
pp. 209-213 ◽  
Author(s):  
Arthur I. Cohen ◽  
Edward H. Frieden

ABSTRACT A number of corticotrophin analogues have been prepared, some of which potentiate the biological activity of the untreated hormone in vitro. The free amino groups of corticotrophin appear to be essential not only for hormonal activity, but also for the interaction of the analogues with the tissue corticotrophin inactivating system which is assumed to account for the potentiating effect.





HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 557d-557
Author(s):  
Jennifer Warr ◽  
Fenny Dane ◽  
Bob Ebel

C6 volatile compounds are known to be produced by the plant upon pathogen attack or other stress-related events. The biological activity of many of these substances is poorly understood, but some might produce signal molecules important in host–pathogen interactions. In this research we explored the possibility that lipid-derived C6 volatiles have a direct effect on bacterial plant pathogens. To this purpose we used a unique tool, a bacterium genetically engineered to bioluminesce. Light-producing genes from a fish-associated bacterium were introduced into Xanthomonas campestris pv. campestris, enabling nondestructive detection of bacteria in vitro and in the plant with special computer-assisted camera equipment. The effects of different C6 volatiles (trans-2 hexanal, trans-2 hexen-1-ol and cis-3 hexenol) on growth of bioluminescent Xanthomonas campestris were investigated. Different volatile concentrations were used. Treatment with trans-2 hexanal appeared bactericidal at low concentrations (1% and 10%), while treatments with the other volatiles were not inhibitive to bacterial growth. The implications of these results with respect to practical use of trans-2 hexanal in pathogen susceptible and resistant plants will be discussed.



2020 ◽  
Vol 27 (1) ◽  
pp. 54-77 ◽  
Author(s):  
Bogdan Bumbăcilă ◽  
Mihai V. Putz

Pesticides are used today on a planetary-wide scale. The rising need for substances with this biological activity due to an increasing consumption of agricultural and animal products and to the development of urban areas makes the chemical industry to constantly investigate new molecules or to improve the physicochemical characteristics, increase the biological activities and improve the toxicity profiles of the already known ones. Molecular databases are increasingly accessible for in vitro and in vivo bioavailability studies. In this context, structure-activity studies, by their in silico - in cerebro methods, are used to precede in vitro and in vivo studies in plants and experimental animals because they can indicate trends by statistical methods or biological activity models expressed as mathematical equations or graphical correlations, so a direction of study can be developed or another can be abandoned, saving financial resources, time and laboratory animals. Following this line of research the present paper reviews the Structure-Activity Relationship (SAR) studies and proposes a correlation between a topological connectivity index and the biological activity or toxicity made as a result of a study performed on 11 molecules of organophosphate compounds, randomly chosen, with a basic structure including a Phosphorus atom double bounded to an Oxygen atom or to a Sulfur one and having three other simple covalent bonds with two alkoxy (-methoxy or -ethoxy) groups and to another functional group different from the alkoxy groups. The molecules were packed on a cubic structure consisting of three adjacent cubes, respecting a principle of topological efficiency, that of occupying a minimal space in that cubic structure, a method that was called the Clef Method. The central topological index selected for correlation was the Wiener index, since it was possible this way to discuss different adjacencies between the nodes in the graphs corresponding to the organophosphate compounds molecules packed on the cubic structure; accordingly, &quot;three dimensional&quot; variants of these connectivity indices could be considered and further used for studying the qualitative-quantitative relationships for the specific molecule-enzyme interaction complexes, including correlation between the Wiener weights (nodal specific contributions to the total Wiener index of the molecular graph) and the biochemical reactivity of some of the atoms. Finally, when passing from SAR to Q(uantitative)-SAR studies, especially by the present advanced method of the cubic molecule (Clef Method) and its good assessment of the (neuro)toxicity of the studied molecules and of their inhibitory effect on the target enzyme - acetylcholinesterase, it can be seen that a predictability of the toxicity and activity of different analogue compounds can be ensured, facilitating the in vivo experiments or improving the usage of pesticides.



2019 ◽  
Vol 16 (3) ◽  
pp. 175-180
Author(s):  
Fengjin Hao ◽  
Yueqin Feng ◽  
Yifu Guan

Objective: To verify whether the botulinum toxin heavy chain HCS has specific neuronal targeting function and to confirm whether TAT-EGFP-LC has hydrolyzable SNAP-25 and has transmembrane biological activity. Methods: We constructed the pET-28a-TAT-EGFP-HCS/LC plasmid. After the plasmid is expressed and purified, we co-cultured it with nerve cells or tumors. In addition, we used Western-Blot to identify whether protein LC and TAT-EGFP-LC can digest the protein SNAP-25. Results: Fluorescence imaging showed that PC12, BV2, C6 and HeLa cells all showed green fluorescence, and TAT-EGFP-HCS had the strongest fluorescence. Moreover, TAT-EGFP-LC can hydrolyze intracellular SNAP-25 in PC12 cells, C6 cells, BV2 cells and HeLa, whereas LC alone cannot. In addition, the in vivo protein TAT-EGFP-HCS can penetrate the blood-brain barrier and enter mouse brain tissue. Conclusion: TAT-EGFP-HSC expressed in vitro has neural guidance function and can carry large proteins across the cell membrane without influencing the biological activity.



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