Producción de (+)-discodermólido por la esponja Discodermia dissoluta bajo sistemas de cultivo fijo y suspendido

The macrolide (+)-discodermolide produced by the marine sponge Discodermia dissoluta shows promising antitumor, antimitotic, and immunosuppressive activity. However, the sustainable supply of any molecule requires much in situ and in vitro research to optimize and later obtain the molecule of interest. In this study, two culture systems—fixed and suspended—were evaluated at 15-m depth in two sites, Punta de Betín and Nenguange, in Santa Marta (Colombian Caribbean). Survival, growth, and production of (+)-discodermolide were recorded, with the suspended system resulting in better growth and survival, depending on the culture site. The influence of the different environmental factors on survival was also studied, and a negative correlation with temperature was observed. Salinity, solar radiation, organic matter, and water flow were not correlated. Finally, no significant differences in the production of (+)-discodermolide existed between the culture systems and study sites. Production ranged from 20 to 270 μg per gram of dry sponge.

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In vitro estimation of rumen fermentable organic matter using enzymes

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v44i2.550 ◽

1996 ◽

Vol 44 (2) ◽

pp. 103-110 ◽

Cited By ~ 2

Author(s):

J.W. Cone ◽

A.H. Van Gelder ◽

A.M. Van Vuuren

Keyword(s):

Organic Matter ◽

Crude Fibre ◽

Fermentation Products ◽

In Situ Method ◽

Degradation Rates ◽

Digestible Organic Matter ◽

Similar Accuracy ◽

The Relationship

The amount of rumen fermentable organic matter (FOM) can be calculated using tables, taking into account the amount of digestible organic matter, the content of fat and fermentation products, and the amount of starch and protein escaping rumen fermentation, or FOM can be calculated using in situ incubations. An in vitro method is described to predict FOM using amylase and other carbohydrate degrading enzymes. FOM estimated by the enzymic method showed a moderate correlation (Rsuperscript 2 = 0.71) with FOM estimated by the in situ method. The relationship could be improved by separating the high crude fibre samples (Rsuperscript 2 = 0.88) from the other samples (Rsuperscript 2 = 0.77). Because degradation rates with the enzymic method were high compared with the assumed rumen passage rates, it proved that FOM could be predicted with a similar accuracy (Rsuperscript 2 = 0.76 - 0.80) by the undegraded fraction after 24 h.

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In vitro studies on the induction of sporogenous tissue on leaves of cinnamon fern. I. Environmental factors

Canadian Journal of Botany ◽

10.1139/b72-341 ◽

1972 ◽

Vol 50 (12) ◽

pp. 2673-2682 ◽

Cited By ~ 7

Author(s):

William H. Harvey ◽

James D. Caponetti

Keyword(s):

Environmental Factors ◽

Light Intensity ◽

Environmental Conditions ◽

Light Exposure ◽

Progressive Increase ◽

Light Phase ◽

Sporogenous Tissue ◽

Light Darkness

Intact, set III, cinnamon fern cataphyll and frond primordia, which were shown to have no predisposition to fertility in situ, produced sporangia when excised and cultured under sterile conditions in Knudson's medium supplemented with various levels of sucrose and maintained on 11 different regimens of light, darkness, and temperature for 10 weeks. Increasing levels of sucrose resulted in increased fertility under all environmental conditions, but the highest percentage of fertility was obtained under conditions of continuous dark at 26 °C. As the length of the light phase of the photoperiods decreased, a progressive increase in induction of fertile leaves was observed, suggesting that periods of long light exposure are inhibitory to the initiation of sporangia. Conversely, as the light intensity was increased, an inhibition of sporophyll differentiation occurred. Sporangia excised from dark-induced sporophylls and cultured in the light produced viable spores which germinated yielding haploid gametophytes that ultimately produced sporophytes.

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In situ degradability of organic matter, crude protein and cell wall of various tree forages

Animal Science ◽

10.1017/s0003356100037235 ◽

1992 ◽

Vol 55 (1) ◽

pp. 29-34 ◽

Cited By ~ 18

Author(s):

P. Kamatali ◽

E. Teller ◽

M. Vanbelle ◽

G. Collignon ◽

M. Foulon

Keyword(s):

Cell Wall ◽

Organic Matter ◽

Leucaena Leucocephala ◽

Crude Protein ◽

In Vitro Digestibility ◽

Sesbania Sesban ◽

Holstein Friesian ◽

Ruminal Degradation

AbstractLeaves of Leucaena leucocephala, Sesbania sesban and Calliandra callothyrsus were harvested in Rwanda from young shoots at 8 weeks after the first cutting. They were dried, ground and incubated at the same time in polyester bags in three non-lactating Holstein-Friesian cows each fitted with a ruminal cannula. The bags were removed at 0, 2, 4, 8, 24, 48, 72 and 144 h after the start of incubations. The different parameters characterizing extent and rate of ruminal degradation of organic matter (OM), neutral-detergent fibre (NDF), and crude protein (CP) were calculated. In vitro digestibility of residual protein after 24 h and 48 h incubation was also determined. Sesbania sesban had lowest cell wall contents and gave highest ruminal degradability for OM, NDF and CP. Leucaena leucocephala was degraded to a lesser extent, but its undegraded protein had a somewhat higher in vitro digestibility. In contrast, protein of Calliandra callothyrsus was poorly degraded and digested. The proportion and composition of cell wall could not explain these differences in digestion characteristics and other measurements, such as tannins, were incriminated. Increased ruminal incubation time augmented the extent of ruminal degradation and reduced in vitro digestibility of undegraded protein but did not affect the undigestible protein fraction.

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Palatability,in situandin vitronutritive value of dried sainfoin (Onobrychis viciifolia)

The Journal of Agricultural Science ◽

10.1017/s0021859610000523 ◽

2010 ◽

Vol 148 (6) ◽

pp. 723-733 ◽

Cited By ~ 10

Author(s):

H. KHALILVANDI-BEHROOZYAR ◽

M. DEHGHAN-BANADAKY ◽

K. REZAYAZDI

Keyword(s):

Organic Matter ◽

Dry Matter ◽

Nutritive Value ◽

Nutrient Content ◽

Gas Production ◽

Metabolizable Energy ◽

Acid Detergent Fibre

SUMMARYThe current study was conducted to determine chemical composition, nutrient content and availability, metabolizable energy (ME) content and nutritive value of sainfoin hay for ruminants. Three ruminally cannulated Holstein cows were used forin situandin vivoexperiments, to determine rumen degradability and digestibility of sainfoin hay. Apparent total tract digestibility of nutrients was determined with feeding of sainfoin hay as the sole diet to achieve 10% more than maintenance energy requirements. Six Zandi ewes were used in the palatability experiment. Means for dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF) and condensed tannins (CTs) of sainfoin hay were: 940·4 g/kg and 93·43, 12·13, 47·87, 43·33 and 2·13 g/kg DM, respectively.In situeffective degradability of CP and DM were 0·38 and 0·54 g/g with a ruminal outflow rate of 0·05/h, respectively. OM apparent digestibility was in the range of 0·592–0·689, respectively, for Tilley & Terry and total faecal collection assays. ME content of sainfoin hay, according to different methods (gas production,in vitroandin vivodetermined digestible organic matter in dry matter (DOMD)) was in the range 6·87–10·11 MJ/kg DM. Metabolizable protein (MP) content was 483·4 g/kg CP. Sainfoin was more palatable than alfalfa for sheep. It was concluded that sainfoin has a potential use in ruminant rations, especially if environmental conditions are not suitable for alfalfa production.

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Rumen degradability of organic matter, nitrogen and fibre fractions in forages

Animal Science ◽

10.1017/s0003356100012551 ◽

1990 ◽

Vol 51 (3) ◽

pp. 515-526 ◽

Cited By ~ 24

Author(s):

P. Susmel ◽

B. Stefanon ◽

C. R. Mills ◽

M. Spanghero

Keyword(s):

Organic Matter ◽

Regression Analysis ◽

Rate Constants ◽

Dry Matter ◽

Maize Silage ◽

Sodium Dichromate ◽

Outflow Rate ◽

Main Component

ABSTRACTRumen degradability of dry matter (DM), organic matter (OM), nitrogen (N), neutral-detergent fibre (NDF), hemicellulose, cellulose and lignin was evaluated with the in situ technique for maize silage and cocksfoot, timothy, fescue, lucerne and meadow hays. The degradability of each of the six forages was studied separately, each forage being used in turn as the main component of the diet offered to four fistulated cows. For each forage 300 g were mordanted with sodium dichromate and placed in the rumen when the same forage was studied. Faecal grab samples were collected to measure the forage transit time. Digestibility was evaluated using both lignin as an indicator and by an in vitro method.Rumen outflow rate was higher for cocksfoot and lucerne hays than for maize silage and the meadow, timothy and fescue hays (P < 0·01). The effective degradabilities of DM and OM were higher in maize silage, fescue and lucerne than in cocksfoot, timothy or meadow hay (P < 0·01). Effective degradability of N was highest in lucerne and lowest in timothy and meadow hay (P < 0·01). The degradability of NDF, hemicellulose and cellulose for fescue was always the highest of the six forages (P < 0·01; P < 0·05; F < 0·01 respectively).Rumen outflow rate was statistically correlated with the c value of DM (r = 0·47), N (r = 0·54), NDF (r = 0·43) and hemicellulose (r = 0·43). High correlations were observed between rate constants of degradation of NDF and hemicellulose, cellulose or lignin (0·93, 0·75 and 0·79 respectively). The regression between in vitro and lignin-derived digestibility was highly significant (P < 0·001, r2 = 0·902 residual s.e. 0·017). The multiple regression analysis between lignin-based digestibility and degradability coefficients, effective degradability and coefficients of faecal chromium excretion was highly significant (r = 0·748; residual s.e. = 0·03).

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In vitro estimation of rumen fermentable organic matter using rumen fluid and a cell free preparation of rumen fluid

Netherlands Journal of Agricultural Science ◽

10.18174/njas.v42i4.593 ◽

1994 ◽

Vol 42 (4) ◽

pp. 343-356 ◽

Cited By ~ 3

Author(s):

J.W. Cone ◽

A.H. Van Gelder ◽

E.T. Veerman ◽

A.M. Van Vuuren

Keyword(s):

Organic Matter ◽

Rumen Fluid ◽

Good Prediction ◽

Feed Composition ◽

In Vitro Methods ◽

In Situ Method ◽

A Cell

The amount of microbial protein leaving the rumen is considered as a function of the amount of rumen-fermentable organic matter (FOM) in the rumen. FOM can be calculated using tables, or estimated by in situ incubation, but both methods have some drawbacks. In vitro methods were therefore developed to estimate FOM, using fresh rumen fluid or a cell-free preparation of rumen fluid. Results were compared with the in situ method and a method using chemical feed composition. The in vitro methods gave a good prediction of the in situ estimation of FOM for the majority of feeds. For some feeds rich in starch or fat, the correlation was poor. Because no in vivo data of FOM were available, it could not be determined whether the in vitro or in situ methods gave false results. However, arguments suggest that the in situ method is not suitable for some feeds.

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Étude de divers paramètres en vue de la culture in vitro des ovules de Capsella bursa-pastoris

Canadian Journal of Botany ◽

10.1139/b83-391 ◽

1983 ◽

Vol 61 (12) ◽

pp. 3471-3477 ◽

Cited By ~ 6

Author(s):

Jean Lagriffol ◽

Michel Monnier

Keyword(s):

Sucrose Concentration ◽

Initial Length ◽

Ovule Development ◽

Growth Study ◽

Culture In Vitro ◽

Growth And Survival ◽

Exponential Curve ◽

Preliminary Study

Some criteria useful for the analysis of the development of embryos in fertilized ovules cultured in vitro were examined in this preliminary study. At first, it was necessary, in order to know the initial length of the embryo at time of inoculation without opening the ovule, to establish a relation between the size of the ovule and the length of the embryo. The study of the variation of length of the embryo according to the size of ovule in situ is expressed by an exponential curve whose equation is established. The choice of ovules for inoculation was made considering both the graph and the survival of embryos in ovules cultivated in vitro. The 6-day period of culture was determined by examining ovule growth. Study of ovule development, embryo growth and survival led to the choice of an optimal sucrose concentration of 80 g/L.

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Prediction of in vivo organic matter digestibility of beef cattle diets from degradation parameters estimated from in situ and in vitro incubations

The Journal of Agricultural Science ◽

10.1017/s0021859620000180 ◽

2019 ◽

Vol 157 (9-10) ◽

pp. 711-720

Author(s):

Pedro Del Bianco Benedeti ◽

Sebastião de Campos Valadares Filho ◽

Diego Zanetti ◽

Fabyano Fonseca e Silva ◽

Breno de Castro Silva ◽

...

Keyword(s):

Organic Matter ◽

Beef Cattle ◽

Fixed Effects ◽

Stepwise Regression ◽

Meta Analysis ◽

Insoluble Fraction ◽

Water Soluble

AbstractThe objective of this meta-analysis study was to develop and validate equations estimated from in situ and in vitro methods to predict in vivo ruminal digestibility of organic matter (OM) of beef cattle diets. The database was composed of individual data of 23 diets from six experiments. Information collected from these studies was: in vivo digestibility and degradation parameters of OM calculated from in situ and in vitro incubations. The values of estimated times for the in situ and in vitro incubations to access in vivo digestibility of OM, and differences between degradation at 24, 48 and 72 h (in situ and in vitro) and in vivo digestibility were analysed in a model that included the fixed effects of forage neutral detergent fibre level. Thereafter, a multiple stepwise regression was carried out using OM digestibility as a dependent variable and degradation parameters (A = water-soluble fraction; B = potentially degradable water-insoluble fraction; and kd = degradation rate of fraction B) as independent variables. Equation validation was performed using data from a seventh experiment that have the same methods than previous studies. Stepwise regression results showed that the kd contributed significantly in most of the algorithms derived to predict in vivo digestibility. Validation analysis showed that equations developed from both in vitro and in situ incubations accurately estimated the in vivo digestibility of OM (P > 0.05). Our results suggest that equations developed to estimate OM digestibility showed both precision and accuracy; however, in situ method presented better results than in vitro.

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