Lipids and calcium uptake of sperm in relation to cold shock and preservation: a review

1993 ◽  
Vol 5 (6) ◽  
pp. 639 ◽  
Author(s):  
IG White
Keyword(s):  
Fatty Acid ◽  
Calcium Uptake ◽  
Cold Shock ◽  
Freezing Point ◽  
Fatty Acid Content ◽  
Calcium Flux ◽  
High Unsaturated Fatty Acid ◽  
High Calcium ◽  
Ram Sperm

When sperm of the ram, bull, boar and stallion are cold-shocked by rapid cooling to near freezing point, motility and metabolic activity are irreversibly depressed and the acrosome and plasma membrane disrupted. Ram sperm become susceptible to cold shock in the proximal corpus region of the epididymis when the cytoplasmic droplet has moved backwards to the distal portion of the sperm midpiece. The membrane constituents phospholipids and cholesterol are important in cold shock which causes loss of lipid from sperm. The susceptibility of sperm to cold shock is linked with a high ratio of unsaturated:saturated fatty acids in the phospholipids and a low cholesterol content. The high unsaturated fatty acid content of sperm also makes them susceptible to damage from peroxidation which adversely affects motility, metabolism, ultrastructure and fertility. Hydroxynonenal, a product of fatty acid peroxidation, depresses the motility and oxygen uptake of ram sperm in vitro and may react with the -SH groups of the axonemal microtubules. High calcium concentrations in the external medium may decrease the motility and metabolism of sperm and 'calcium intoxication' may be a factor in cold shock. Lowering the environmental temperature increases calcium uptake by sperm and the effect is aggravated if the rate of cooling is rapid. Phospholipids, particularly those in egg yolk, protect sperm to some extent from cold shock and also prevent increased calcium flux into the sperm. Suggestions are made for increasing the life span of sperm during preservation and microencapsulation by adding agents that may stabilize membranes, counter peroxidation and decrease calcium uptake.

A comprehensive study on the improvement of oxidation stability and NOx emission levels by antioxidant addition to biodiesel blends in a light-duty diesel engine

RSC Advances ◽  
2016 ◽  
Vol 6 (27) ◽  
pp. 22436-22446 ◽  
Author(s):  
M. M. Rashed ◽  
H. H. Masjuki ◽  
M. A. Kalam ◽  
Abdullah Alabdulkarem ◽  
H. K. Imdadul ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Diesel Engine ◽  
Unsaturated Fatty Acid ◽  
Moringa Oleifera ◽  
Fatty Acid Content ◽  
Oxidation Stability ◽  
High Unsaturated Fatty Acid ◽  
Light Duty ◽  
Biodiesel Feedstock ◽  
Comprehensive Study

Moringa oleifera oil, a non-edible biodiesel feedstock with high unsaturated fatty acid content, was used in this study.

scholarly journals Teosinte (Dioon mejiae) Flour: Nutritional and Physicochemical Characterization of the Seed Flour of the Living Fossil in Honduras

Agronomy ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 481
Author(s):  
José-Miguel Bastias-Montes ◽  
Laura-Elena Flores-Varela ◽  
Onán-Alonso Reyes-Calderón ◽  
Carla Vidal-San-Martín ◽  
Ociel Muñoz-Fariña ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Content ◽  
Physicochemical Characterization ◽  
Sodium Concentration ◽  
Essential Amino Acids ◽  
High Unsaturated Fatty Acid ◽  
Total Dietary Fiber ◽  
Living Fossil ◽  
Physicochemical Composition ◽  
Seed Flour

Teosinte (Dioon mejiae) is a dioecious tree native to Honduras, whose seeds are used to make flour for the preparation of traditional foods and beverages. The objective was to evaluate the nutritional and physicochemical composition of teosinte flour for the first time. Using diverse techniques, teosinte flour was found to be a high-calorie food rich in total carbohydrates and mainly composed of starch, with an amylopectin:amylose ratio of 2:1 and a concentration of resistant starch greater than 50%. Its proteins were similar to other cereals in which the essential amino acids glutamic acid, leucine, and especially lysine were the most important. Some 75% of its total dietary fiber was insoluble. The fatty acid profile was characterized by a high unsaturated fatty acid content in which oleic acid (C18:1) and linoleic acid (C18:2) predominated. As for minerals, teosinte flour had higher iron content, lower sodium concentration, and similar zinc, calcium, and phosphorus content to other cereal flours. We highlight that teosinte flour has nutrients and qualities that convert it into flour with excellent nutritional abilities and health benefits; it is also a very good industrial and technological alternative to be mixed mainly with types of flour from other sources.

Differences in chemical composition between nonflocculated and flocculated Azospirillum brasilense Cd

1998 ◽  
Vol 44 (4) ◽  
pp. 386-390 ◽  
Author(s):  
Olubayi Olubayi ◽  
Rodulio Caudales ◽  
Amy Atkinson ◽  
Carlos A Neyra
Keyword(s):  
Fatty Acid ◽  
Azospirillum Brasilense ◽  
Unsaturated Fatty Acids ◽  
De Novo ◽  
Fatty Acid Content ◽  
Fatty Acid Profiles ◽  
Replacement Method ◽  
Replacement Procedure ◽  
Beta Hydroxybutyrate

A two-step broth replacement method was used to induce Azospirillum brasilense Cd bacteria to flocculate in vitro. Nonflocculated and flocculated cells were compared with regard to total cellular lipid composition, fatty acid profiles, and poly-beta-hydroxybutyrate (PHB), protein, and carbohydrate contents. The fatty acid profiles of nonflocculated and flocculated cells were qualitatively identical. Two unsaturated fatty acids, octadecanoate (18:1 cis-9) and hexadecanoate (16:1 cis-9), accounted for approximately 80% of the total fatty acid content in both phenotypes. The major lipids in nonflocculated and flocculated A. brasilense Cd cells were phosphatidylethanolamine, phosphatidylglycerol, and phosphatidylcholine. The process of flocculation also resulted in the synthesis de novo of a glycolipid and cardiolipin. Flocculation also resulted in a decrease in total cellular protein and lipid content and a proportional increase in total cellular PHB and carbohydrate content. Results indicated that the two-step broth replacement procedure was an effective means for the in vitro production of the stress-tolerant A. brasilense Cd cells with high PHB contents, which are desirable in commercial agricultural inocula. The PHB content of flocculated cells reached 60-65% of cell dry weight.Key words: Azospirillum, flocculation, poly-beta-hydroxybutyrate, PHB, lipid, protein, carbohydrate, fatty acid.

Consequences of exposure to serum, with or without vitamin E supplementation, in terms of the fatty acid content and viability of bovine blastocysts produced in vitro

2003 ◽  
Vol 15 (5) ◽  
pp. 275 ◽  
Author(s):  
A. Reis ◽  
J. A. Rooke ◽  
G. J. McCallum ◽  
M. E. Staines ◽  
M. Ewen ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Vitamin E ◽  
Acid Content ◽  
Fatty Acid Content ◽  
Calf Serum ◽  
Pyruvate Metabolism ◽  
Cell Counts ◽  
Serum Supplementation ◽  
Development In Vitro

To determine whether serum supplementation influenced fatty acid content of bovine blastocysts and whether vitamin E addition to culture medium containing serum could improve development in vitro, cleaved eggs were cultured in synthetic oviduct fluid supplemented with bovine serum albumin (BSA, 0.4% w/v, fraction V) (SVBSA), fetal calf serum (FCS, 10% v/v) (SFCS) or FCS (10% v/v) plus 100 μM vitamin E (SFCS + E). Blastocyst yields were recorded and fatty acid composition was determined by gas chromatography. Day 7 blastocysts were incubated with [2-14C] pyruvate for 3 h and then fixed for cell counts. Yields of good quality blastocysts were greatest from cleaved eggs cultured in serum-free conditions (P < 0.01). In the presence of serum, supplementation with vitamin E increased both total and good quality blastocyst yields (P < 0.01). Presence of serum increased fatty acid content (mean ± SEM) of blastocysts (SVBSA v. SFCS = 57 ± 2  v. 74 ± 2 ng embryo−1; P < 0.001). In contrast, pyruvate metabolism was greater in blastocysts produced without serum (27 ± 3 v. 21 ± 3 picomoles embryo−13 h−1; P < 0.01) but, on a per cell basis, no differences were detected. Addition of vitamin E to the serum-supplemented formulation did not alter either the fatty acid content (73 ± 2 ng embryo−1) or pyruvate metabolism index (19 ± 1 pmol embryo−13 h−1) of SFCS + E blastocysts. Thus, despite lipid accumulation, supplementary vitamin E improved blastocyst yields in embryos exposed to serum.

Composition of milk cephalins

1968 ◽  
Vol 46 (3) ◽  
pp. 205-210 ◽  
Author(s):  
G. M. Moore ◽  
J. B. M. Rattray ◽  
D. M. Irvine
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Human Milk ◽  
Unsaturated Fatty Acids ◽  
Fatty Acid Content ◽  
Phosphatidyl Serine ◽  
Variable Component ◽  
Layer Chromatography ◽  
Palmitic Acids

Lipid was extracted from lyophilized samples of cow, goat, sheep, horse, and human milk. The cephalins were isolated by thin-layer chromatography and ascertained to be the major, but variable component of all milk phospholipids examined except in the case of the horse. The predominant cephalin type was found to be phosphatidyl ethanolamine (PE), while phosphatidyl serine (PS) was determined to be either absent or to account for approximately 20% of the total cephalins. Lysocephalins were generally absent. The fatty acid composition of PE and PS was characterized by high levels of oleic and palmitic acids and by the virtual lack of long-chain polyunsaturated fatty acids. Individual differences in fatty acid content were slight among members of the same species, but human milk PE showed considerable variations in composition. PE was determined to be more highly unsaturated than PS with the unsaturated fatty acids occurring primarily at the β-position of the PE molecule. The results obtained on the chemical structure of milk cephalins have been discussed in relationship to the suggested activity of these compounds on the blood coagulation process in vitro.

Glucose enhancement of transcellular calcium transport in the intestine

1988 ◽  
Vol 255 (3) ◽  
pp. G339-G345 ◽  
Author(s):  
K. M. Carroll ◽  
R. J. Wood ◽  
E. B. Chang ◽  
I. H. Rosenberg
Keyword(s):  
Calcium Transport ◽  
Calcium Uptake ◽  
Calcium Absorption ◽  
Membrane Integrity ◽  
Calcium Flux ◽  
Calcium Efflux ◽  
Cell Membrane Integrity ◽  
Active Calcium ◽  
Altered Cell

Glucose stimulates calcium transport in vitro in rat duodenal tissue and isolated enterocytes. Under short-circuited conditions, glucose increased mucosal to serosal calcium flux (JCa(m----s)) without altering serosal to mucosal calcium flux (JCa(s----m)) in the duodenum, the primary site of active calcium absorption in the rat small intestine. The half-maximal dose (ED50) of the glucose stimulatory effect was less than 1 mM, and an increase in JCa(m----s) of 80% over control was seen at a glucose concentration of 50 mM. Glucose did not increase calcium flux in the ileum where active calcium absorption is minimal. Glucose stimulated net calcium uptake by 35% in isolated duodenal enterocytes. Glucose did not alter calcium efflux from preloaded enterocytes suspended in calcium-free buffer. Glucose enhancement of net calcium uptake in enterocytes was not caused by altered cell membrane integrity or functional viability. The nonmetabolizable glucose analogue alpha-methylglucoside did not stimulate calcium transport. Our findings suggest that glucose can stimulate intestinal calcium absorption, at least partially, by enhancing transcellular calcium transport and that cellular glucose metabolism is necessary for stimulation of this route of calcium transport.

Herbicide Symptomology and the Mechanism of Action of Methiozolin

Weed Science ◽  
2020 ◽  
pp. 1-38
Author(s):  
Chad Brabham ◽  
Philipp Johnen ◽  
Janneke Hendriks ◽  
Michael Betz ◽  
Alexandra Zimmermann ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Mechanism Of Action ◽  
Acid Content ◽  
Fatty Acid Content ◽  
Alpha Tocopherol ◽  
Minor Effect ◽  
Exploratory Research ◽  
Meristematic Tissue ◽  
Mva Pathway

Abstract Methiozolin is a new herbicide for control of annual bluegrass (Poa annua L.) in several warm and cool season turfgrasses with an unknown mechanism of action (MOA). In the literature, methiozolin was proposed to be a pigment inhibitor via inhibition of tyrosine aminotransferases (TATs) or a cellulose biosynthesis inhibitor (CBI). Here, exploratory research was conducted to characterize the herbicide symptomology and MOA of methiozolin. Arabidopsis (Arabidopsis thaliana L.) and P. annua exhibited a similar level of susceptibility to methiozolin and arrestment of meristematic growth was the most characteristic symptomology. For example, methiozolin inhibited Arabidopsis root growth (GR50 8 nM), shoot emergence (GR80 ~50 nM), and at rates greater than 500 nM apical meristem growth was completely arrested. We concluded that methiozolin was neither a TAT nor a CBI inhibitor. Methiozolin had a minor effect on chlorophyll and alpha-tocopherol content in treated seedlings (< 500 nM) and supplements in the proposed TAT pathway could not lessen phytotoxicity. Examination of microscopy root images revealed methiozolin treated (100 nM) and untreated seedlings had similar root cell lengths. Thus, methiozolin inhibits cell proliferation and not elongation from meristematic tissue. Subsequently, we suspected methiozolin was an inhibitor of the mevalonic acid (MVA) pathway because its herbicidal symptomologies were nearly indistinguishable from those caused by lovastatin. However, methiozolin did not inhibit phytosterol production and MVA pathway metabolites did not rescue treated seedlings. Further experiments showed that methiozolin produced a very similar physiological profile across a number of assays as cinmethylin, a known inhibitor of fatty acid synthesis through inhibition of thioesterases (FATs). Experiments with Lemna showed that methiozolin also reduced fatty acid content in Lemna with a profile similar, but not identical, to cinmethylin. However, there was no difference in fatty acid content between treated (1 µM) and untreated Arabidopsis seedlings. Methiozolin also bound to both Arabidopsis and Lemna FATs in vitro. Modeling suggested that methiozolin and cinmethylin have comparable and overlapping binding sites to FAT. While there was a discrepancy in the effect of methiozolin on fatty acid content between Lemna and Arabidopsis, the overall evidence indicates that methiozolin is a FAT inhibitor and acts in a similar manner as cinmethylin.

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