Improvement of sperm motility of Oncorhynchus mykiss and Salvelinus fontinalis by L-tryptophan

Abstract

Experiments were designed to test the influence of L-tryptophan supplementation of the extender on the sperm motility parameters and bacterial flora of brook trout (Salvelinus fontinalis) and rainbow trout (Oncorhynchus mykiss). The extender containing 0.3 M glucose in 10% Dimethyl sulfoxide (DMSO) was supplemented with 0, 0.5, 1, 2, and 4 mM L-tryptophan. Sperm samples stored for up to 12 days at 4°C for brook trout were motile while motility was not observed after six days of storage for rainbow trout. Diluted sperm samples were spread-plated onto Plate Count Agar (PCA) (Total Bacteria Count), Rose Bengal Agar (RBC) (Yeast-Mold Count), Violet Red Bile Dextrose (VRBD) (Enterobacteriaceae count) and Mannitol Salt Agar (MSA) (Micrococcus/ Staphylococcus count) and counts were performed in duplicate and sampling occurred on day 0, 2, 4, 6, and 12 of cold storage. L-tryptophan supplementation of the extender yielded a positive effect, significantly prolonging sperm motility in S. fontinalis and O. mykiss compared to the control group (p < 0.05). The ideal results were obtained above a concentration of 0.5 mM for both species. Total bacteria count in fresh sperm (undiluted samples) was not detectable and not detected in sperm samples treated with different L-tryptophan concentrations. Yeast-mold, Enterobacteriaceae and Micrococcus/Staphylococcus were not detected from fresh and treated sperm brook trout and rainbow trout. On the basis of the results, L-tryptophan-based extender is useful for maintaining sperm quality in short-term storage. L-tryptophan had a negative effect on the bacterial flora. The results of the current study encourages further studies related to longterm storage and reproduction management.

Assessment of Blood Plasma Free-amino Acid Levels in Infertile Men

“…Considering the important roles of AAs in a wide variety of pathophysiological events, we evaluated our findings, focusing only on men with either normospermia or oligozoospermia, and found significantly lower levels of alanine and tryptophan in men with lower motility rates, and lower levels of aspartic acid and glutamic acid in men with higher abnormal morphology rates. To date, a number of studies have reported the effects of these four AAs on sperm function (8,11,14,15,(19)(20)(21)(22)(23)(24). For example, in vitro motility, longevity, and in vivo fertility were enhanced in bull spermatozoa by tryptophan supplementation (11), while oral administration of aspartic acid resulted in the improvement of sperm quality and fertility using a rooster model (20).…”

Analysis of the Microbial Diversity and Characteristics of Fermented Blueberry Beverages from Different Regions

“…The procedure for enumeration of lactic acid bacteria [ 6 ] and yeast [ 25 ] is as follows: A 10-fold gradient dilution was prepared by adding a 25 mL sample to 225 mL sterile saline. The sample solutions with appropriate dilution were chosen and inoculated in MRS agar plates and Rose Bengal agar plates to obtain viable counts of lactic acid bacteria (LAB) and yeast, respectively; the inoculum size was 1 mL.…”

Diet and human reproductive system: Insight of omics approaches

“…Amino acids show an eminent role in multiple biologic and psychological processes and antioxidant properties that are an active primary defense for the protection of sperm membrane structure (Kocabaş et al., 2019 ). In the reproduction process, seminal plasma is a crucial biological fluid that controls sperm function (Table 2 ).…”