Tannin Concentration of Gyrinops Tea Taken Form Different Agarwood Plantation and Different Processing Method

Tannin is one of the essential components that determine the quality of herbal tea products. This research aims to conduct a quantitative tannin assay of Gyrinops tea with different leaf sampling locations and processing methods. Factorial Completely Randomized Design was used as an experimental design with two treatment factors. The first factor is sampling location (Kekait, Lingsar, and Pejaring). The second factor is the processing method (Fresh leaves and Dried leaves). A titrimetric method with KMnO4 and Indigo carmine reagent was used for quantitative tannin measurement. ANOVA and DMRT at a 5% significant level were used for tannin concentration analysis. The result indicated that the first, second, and interaction factors significantly affected tannin concentration. Drying the G. versteegii leaves could increase the tannin concentration of the Gyrinops tea product. G. versteegii leaves taken from Kekait have shown highest tannin concentration among other regions. It could be concluded that dried G. versteegii leaves Kekait could produce Gyrinops tea with high quality based on tannin concentration measurement.

Response of Background Herbivory in Mature Birch Trees to Global Warming

Given the time scale based on the duration of exposure to global warming, natural climate-gradient studies and experimental manipulations have detected long-term (decades to centuries) and short-term (years to decades) ecological responses to global warming. Combination of these two complementary approaches within a single study may enable prediction of the likely responses of ecological processes to global warming. To understand how global warming affects plant–herbivore interactions within a canopy of Erman’s birch, we combined an elevational gradient study and a warming experiment involving mature birch trees in which the soil and tree branches were warmed separately. In the elevational gradient study, herbivory by chewing insects and plant growth increased as elevation decreased, and the concentrations of condensed tannins and total phenolics in the leaves decreased. In the warming experiment, soil warming alone increased herbivory, and the addition of branch warming amplified the effect on herbivory. Soil warming alone decreased the tannin concentration, and the addition of branch warming led to a further reduction. The variation in herbivory was best explained by the tannin content of leaves. Our experimental results demonstrate that the decreased tannin content of leaves due to a combination of soil and branch warming was an important driver of increased herbivory in the canopy of the mature birch trees. The similar tendencies in the short- and long-term responses imply that global warming is likely to increase background herbivory in mature birch trees by decreasing the tannin content of leaves in the canopy.

Generation Times of E. coli Prolong with Increasing Tannin Concentration while the Lag Phase Extends Exponentially

The current study examines the effect of tannins and tannin extracts on the lag phase duration, growth rate, and generation time of Escherichia coli. Effects of castalagin, vescalagin, gallic acid, Colistizer, tannic acid as well as chestnut, mimosa, and quebracho extracts were determined on E. coli’s growth phases using the broth microdilution method and obtained by turbidimetric measurements. E. coli responds to the stress caused by the investigated antimicrobial agents with reduced growth rates, longer generation times, and extended lag phases. Prolongation of the lag phase was relatively small at low tannin concentrations, while it became more pronounced at concentrations above half the MIC. Moreover, for the first time, it was observed that lag time extensions follow a strict exponential relationship with increasing tannin concentrations. This feature is very likely a direct consequence of the tannin complexation of certain essential ions from the growth medium, making them unavailable to E. coli for its growth.

Development of UV-vis and FTIR Partial Least Squares models: comparison and combination of two spectroscopy techniques with chemometrics for polyphenols quantification in red wine

Polyphenolic compounds are considered to have a major impact on the quality of red wines. Sensory perception, such as astringency and bitterness, are mainly related to condensed tannin, while colour intensity and evolution is due to anthocyanin composition. Therefore, the quick analytical measurement of phenolic compounds appears to be a real challenge for wine monitoring. Fourier transform infrared (FTIR) and ultraviolet-visible (UV-vis) spectroscopy with chemometrics are good candidates for predicting polyphenolic contents in wines, but they have not yet been compared in terms of efficiency of each wavelength area. Thus, the possibility of combining the two areas has not been investigated.This work sought to determine the tannin and anthocyanin content of ninety-two wines. The wine selection covered different vintages, varieties and regions. Tannin concentration was analysed by precipitation with protein and polysaccharide and by the Bate-Smith assay. Free anthocyanin concentration was analysed by bisulfite bleaching and the monomers/polymers ratio was analysed using the Adams-Harbertson method. Molecular anthocyanin concentration was also obtained by HPLC/UV-vis. Two spectra were collected using UV-vis and FTIR devices. The data collected were statistically analysed using the partial least squares (PLS) regression method.The correlations obtained were relevant to both of the spectrum areas studied, with a coefficient of determination for cross validation larger than 0.7 for most parameters studied. While the two spectroscopic methods gave almost identical results, FTIR indicated higher robustness for the prediction of tannin concentration. Conversely, UV-vis appeared to be more relevant when determining anthocyanin concentration and evolution. Finally, the models obtained when combining the two spectrum areas gave slightly better results. When a selection of different visible wavelengths were added to the FTIR spectrum, the results showed that the prediction of anthocyanin parameters improved considerably, thus highlighting the importance of the visible area when estimating these compounds.

Effects of polyphenols on plankton assemblages and bacterial abundance representative of a pampean shallow lake: an experimental study

Shallow lakes are complex environments that play an important role in ecology. Their relationships with the surrounding areas make these lentic water bodies susceptible to alterations in response to human activity. For example, the input of polyphenols could be critical in altering species interactions. The shallow lakes located in the pampean plain of Argentina are major reservoirs of diversity, with the environmental habitats of the Salado River basin in particular having become impacted by human activities. The aim of this work was to evaluate the effects of different polyphenol concentrations (i.e. tannins) on changes in the plankton assemblages and on the abundance of bacteria in San Miguel del Monte Lake. Factorial experiments under laboratory conditions (4 tannin concentration levels and 4 response times) revealed that high tannin concentrations affected neither the phyto- and zooplankton assemblages nor bacterial abundances. Major changes both in assemblages and in the bacterioplankton abundances were dependent on exposure time. We found that the initial food web of grazers shifted to detritivorous feeding, thus producing a simplification of the community toward early succession. Although no effects of polyphenols were registered here, what proved striking was the resilience of the system and the capability to support high tannin concentrations throughout the experiment. Therefore, future investigations are necessary to elucidate the key role of such humic substances in the structuring of plankton assemblages of shallow lakes from strongly impacted areas, such as those found in the pampean region.

Effect of tannin concentration on mycelial growth and development of Auricularia cornea

It is proved that the effect of tannin concentration on the mycelial growth of fungi. Auricularia cornea (white strain) were treated with different concentrations of tannins in petri-dishes and liquid shaking flasks. The growth rate of mycelium, the ratio of clamp connection, morphology of mycelium, biomass of mycelium and activity of antioxidant enzymes were determined. The results showed that different concentrations of tannin significantly decreased the rate of mycelium. However hign concentration of tannin stress increased the content of thiobarbituric acid in mycelia and had obvious time and concentration effects. Different antioxidant enzyme activities also had different responses to tannin stress. It provides theoretical basis for fungi to utilize and develop substrates containing tannin such as pine.

Effect of tannin concentration on mycelial growth and development of Auricularia cornea

It is proved that the effect of tannin concentration on the mycelial growth of fungi. Auricularia cornea (white strain) were treated with different concentrations of tannins in petri-dishes and liquid shaking flasks. The growth rate of mycelium, the ratio of clamp connection, morphology of mycelium, biomass of mycelium and activity of antioxidant enzymes were determined. The results showed that different concentrations of tannin significantly decreased the rate of mycelium. However hign concentration of tannin stress increased the content of thiobarbituric acid in mycelia and had obvious time and concentration effects. Different antioxidant enzyme activities also had different responses to tannin stress. It provides theoretical basis for fungi to utilize and develop substrates containing tannin such as pine.

Effect of Tannin Concentration on Mycelial Growth and Development of Auricularia Cornea

It is proved that the effect of tannin concentration on the mycelial growth of fungi. Auricularia cornea (white strain) were treated with different concentrations of tannins in Petri-dishes and liquid shaking flasks. The growth rate of mycelium, the ratio of clamp connection, morphology of mycelium, biomass of mycelium and activity of antioxidant enzymes were determined. The results showed that different concentrations of tannin significantly decreased the rate of mycelium. However hign concentration of tannin stress increased the content of thiobarbituric acid in mycelia and had obvious time and concentration effects. Different antioxidant enzyme activities also had different responses to tannin stress. It provides theoretical basis for fungi to utilize and develop substrates containing tannin such as pine.

Penentuan Pelarut Terbaik pada Ekstraksi Tanin Kulit Kayu Akasia dan Pengaruhnya Sebagai Inhibitor Laju Korosi pada Baja Karbon

Peralatan industri dari baja karbon yang berkontak langsung dengan lingkungan lama kelamaan akan terkorosi. Laju korosi dapat diperlambat menggunakan inhibitor organik senyawa tanin dari pohon akasia. Tanin diperoleh dari proses ekstraksi menggunakan metanol dan etanol. Tujuan dari penelitian ini adalah menentukan pelarut terbaik dalam proses ekstraksi kulit kayu akasia berdasarkan kandungan tanin terbesar serta mempelajari pengaruh tanin sebagai inhibitor korosi pada baja karbon dalam media korosif melalui metode pengurangan berat. Proses ekstraksi menggunakan metode maserasi pada suhu ruang selama dua jam dengan perbandingan padatan:pelarut adalah 1:10. Pelarut yang digunakan adalah etanol dan metanol. Ekstrak dievaporasi dalam rotary evaporator pada suhu 50 oC, tekanan 100 mbar hingga membentuk pasta. Ekstrak kulit kayu ditambahkan sebagai inhibitor dalam media korosif H2SO4 0,5 M; HCl 0,5 M; air laut, dan air tanah dengan penambahan konsentrasi inhibitor sebesar 4%, 6% dan 8% (b/v). Perendaman dilakukan selama 12, 24, 36, 48, 60 dan 72 jam. Metanol merupakan pelarut yang lebih baik daripada etanol dengan perolehan yield 4,57% dan konsentrasi tanin sebesar 2,768 ppm. Tanin dalam ekstrak kulit kayu akasia cocok digunakan sebagai inhibitor korosi pada media asam seperti H2SO4 0,5 M dan HCl 0,5 M dengan perolehan efisiensi tertinggi secara berturut-turut adalah 81,20 % dan 53,06%.Carbon steel in industrial equipment which direct contact with the environment will eventually be corroded. The rate of corrosion could be slowed by organic inhibitors of tannin compounds contained from acacia trees. Tannins were obtained from the extraction process using methanol and ethanol. The aims of this research were to determine the best solvent in the extraction process of acacia bark based on the largest tannin content and to study the effect of tannin as a corrosion inhibitor on carbon steel in the corrosive media through weight reduction methods. The extraction process used maceration at room temperature for two hours with a solid:solvent ratio of 1:10. The solvents were ethanol and methanol. The extract was evaporated in a rotary evaporator at 50 oC, 100 mbar became a paste form. Bark extract was added as an inhibitor in 0.5 M H2SO4 corrosive media; HCl 0.5 M; sea water, and tap water with the addition of inhibitor concentrations of 4%, 6% and 8% (w /v). Immersion was carried out for 12, 24, 36, 48, 60 and 72 hours. Methanol was a better solvent than ethanol with a yield of 4.57% and tannin concentration of 2.768 ppm. Tannin in acacia bark extract is suitable to be used as a corrosion inhibitor in acidic media such as H2SO4 0.5 M and 0.5 M HCl with the highest efficiency gains are 81.20% and 53.06%, respectively.

Acacia mearnsii tannin extract as a feed additive: impact on feed intake, digestibility and nitrogen excretion by sheep fed a tropical grass-based diet

ABSTRACT: The aim of this study was to evaluate the effect of the dietary inclusion of Acacia mearnsii tannin extract (TA) on nutrients intake and digestibility, and nitrogen (N) retention by sheep given a tropical grass-based diet. The trial was conducted with six castrated male sheep in a cross-over design in two 21-days experimental periods. The sheep were housed in metabolic cages and offered Tifton 85 hay (Cynodon dactylon) ad libitum plus concentrate at a rate of 12 g of dry matter (DM)/kg body weight (BW). The treatments were concentrate without (Control) or with 10 g TA/kg DM (Tannin). Concentration of TA in the diet was 3.8 g/kg DM and did not affect the feed intake or apparent digestibility. The TA decreased the true digestibility of n compounds (P<0.05) whereas did not impact the N retention, microbial N flow to the small intestine or the efficiency of rumen microbial protein synthesis. In conclusion, a low dietary concentration of TA did not impact the nutrients supply and N use by sheep fed with a tropical grass-based diet.