1. Introduction
2. Results
2.1. Chemical Composition
2.2. Sperm Morpho-Functional Parameters
2.3. Sperm Morphological Evaluation by Scanning Electron Microscopy
3. Discussion
4. Materials and Methods
4.1. Chemo-Characterization of the M. alternifolia EO
4.1.1. Gas Chromatography-Mass Detector (GC-MS) Analysis
4.1.2. Gas Chromatography-Flame Ionization Detector (GC-FID) Analysis
4.1.3. Qualitative and Semi-Quantitative Analysis
4.2. Boars and Ejaculates
4.3. Experimental Protocol
4.4. Evaluation of Spermatozoa Morpho-Functional Parameters
4.5. Scanning Electron Microscopy
4.6. Statistical Analyses
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Sample Availability: Samples of the compounds used in the present study are available from the authors. |





Compound | LRI 1 | Area% |
---|---|---|
terpinen-4-ol | 1185 | 41.49 |
γ-terpinene | 1061 | 20.55 |
α-terpinene | 1018 | 9.59 |
α-terpineol | 1194 | 4.42 |
α-pinene | 933 | 4.4 |
p-cymene | 1025 | 3.66 |
terpinolene | 1089 | 3.18 |
1,8-cineole | 1031 | 2.15 |
limonene | 1029 | 1.78 |
aromadendrene | 1446 | 1.38 |
caryophyllene oxide | 1594 | 0.76 |
myrcene | 992 | 0.72 |
allo-aromadendrene | 1468 | 0.18 |
α-felladrene | 1005 | 0.17 |
sabinene | 973 | 0.03 |
β-pinene | 975 | 0.03 |
α-humulene | 1460 | 0.02 |
β-caryophyllene | 1425 | 0.02 |
Total | 94.53 |
TTO (mg/mL) | ||||||
---|---|---|---|---|---|---|
CTR | 0.2 | 0.4 | 0.6 | 0.8 | 1 | |
VAP (μm/s) | 80.96 (2.63) | 77.70 (3.89) | 81.02 (5.63) | 79.04 (4.37) | 72.47 (3.15) | 54.95 (7.87) *** |
VCL (μm/s) | 180.75 (5.62) | 173.34 (8.61) | 186.84 (12.73) | 180.77 (6.22) | 165.14 (6.14) | 132.98 (16.83) ** |
VSL (μm/s) | 41.10 (1.73) | 37.30 (2.00) | 34.35 (2.29) | 33.33 (2.19) | 32.02 (1.27) | 25.36 (2.16) *** |
DAP (μm) | 48.19 (1.39) | 47.37 (1.89) | 49.14 (2.77) | 48.08 (2.41) | 44.78 (2.11) | 36.71 (4.19) ** |
DCL (μm) | 110.20 (3.49) | 106.94 (4.83) | 115.65 (6.59) | 112.55 (3.62) | 104.97 (5.06) | 86.34 (9.86) * |
DSL (μm) | 22.71 (0.79) | 20.88 (0.96) | 18.45 (0.94) * | 18.27 (1.12) * | 18.11 (0.32) * | 15.24 (0.83) *** |
LIN (%) | 22.74 (0.60) | 22.58 (0.55) | 19.54 (0.86) | 20.07 (1.32) | 21.03 (1.25) | 21.41 (1.60) |
STR (%) | 50.90 (1.09) | 48.67 (0.97) | 43.19 (1.28) ** | 43.37 (2.16) * | 46.48 (2.42) | 47.43 (3.03) |
WOB (%) | 45.16 (0.32) | 45.00 (0.35) | 43.64 (0.89) | 44.48 (1.02) | 44.06 (0.83) | 43.96 (0.97) |
ALH (μm) | 9.50 (0.26) | 8.88 (0.38) | 9.55 (0.69) | 10.01 (0.44) | 9.54 (0.66) | 8.65 (1.01) |
BCF(Hz) | 37.75 (1.15) | 37.34 (0.77) | 38.15 (0.99) | 36.60 (2.89) | 34.94 (1.38) | 35.11 (2.75) |
TER (mg/mL) | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
CTR | 0.08 | 0.17 | 0.25 | 0.33 | 0.42 | 0.50 | 0.58 | 0.67 | 0.75 | 0.83 | |
Equivalent to TTO (mg/mL) | |||||||||||
0.2 | 0.4 | 0.6 | 0.8 | 1 | 1.2 | 1.4 | 1.6 | 1.8 | 2 | ||
VAP (µm/s) | 88.12 (2.26) | 92.15 (4.46) | 92.29 (4.22) | 95.19 (5.92) | 90.17 (5.92) | 86.83 (6.27) | 87.91 (5.09) | 87.89 (5.61) | 78.58 (5.71) | 75.39 (6.40) | 75.41 (4.92) |
VCL (µm/s) | 200.47 (5.82) | 212.65 (12.22) | 219.15 (7.81) | 223.22 (8.89) | 212.76 (9.48) | 200.71 (12.55) | 202.52 (11.31) | 203.59 (11.60) | 188.61 (13.59) | 172.23 (12.16) | 170.46 (10.83) |
VSL (µm/s) | 44.32 (1.63) | 44.77 (1.56) | 36.71 (3.73) | 37.25 (1.88) | 36.68 (3.25) | 34.88 (2.86) * | 35.54 (2.87) ** | 33.78 (1.90) ** | 27.72 (2.33) *** | 28.15 (1.97) *** | 29.19 (2.61) *** |
DAP (µm) | 51.32 (1.53) | 54.01 (2.78) | 54.23 (2.78) | 55.39 (3.32) | 53.45 (3.73) | 51.58 (3.34) | 51.15 (3.42) | 50.77 (4.66) | 48.48 (3.01) | 44.37 (4.45) | 45.79 (2.48) |
DCL (µm) | 119.94 (3.40) | 127.73 (8.35) | 132.63 (3.80) | 134.08 (5.57) | 129.96 (7.87) | 123.33 (6.62) | 122.08 (7.39) | 124.67 (7.34) | 121.17 (7.45) | 108.95 (6.67) | 107.95 (6.26) |
DSL (µm) | 23.62 (1.31) | 24.27 (0.98) | 19.08 (2.18) | 19.36 (1.33) | 19.28 (0.99) | 18.06 (0.82) * | 18.25 (0.94) * | 17.88 (1.10) * | 15.32 (1.25) *** | 15.24 (1.10) *** | 16.13 (1.41) *** |
LIN (%) | 22.93 (1.28) | 22.67 (1.68) | 18.15 (1.81) | 18.16 (1.25) | 18.74 (1.42) | 20.09 (1.35) | 17.03 (1.15) * | 17.47 (0.50) * | 15.95 (0.66) * | 16.66 (0.69) * | 16.23 (1.81) ** |
STR (%) | 49.45 (2.11) | 48.83 (2.65) | 41.79 (3.25) | 41.04 (2.60) | 41.66 (2.51) | 41.52 (1.71) | 41.32 (0.91) | 39.64 (1.20) * | 36.99 (1.48) ** | 38.67 (2.19) ** | 39.01 (1.62) ** |
WOB (%) | 10.31 (0.30) | 10.57 (0.59) | 174.74 (0.36) | 11.38 (0.34) | 11.08 (0.52) | 10.95 (0.37) | 43.55 (0.37) | 42.98 (0.68) | 42.28 (0.78) | 43.54 (0.81) | 44.29 (1.16) |
ALH (µm) | 10.31 (0.30) | 10.57 (0.59) | 11.25 (0.39) | 11.38 (0.36) | 33.08 (0.34) | 10.95 (0.52) | 11.44 (0.42) | 11.30 (0.51) | 12.34 (1.59) | 10.67 (0.58) | 10.67 (0.39) |
BCF (Hz) | 45.05 (3.30) | 43.52 (3.95) | 48.68 (7.60) | 42.48 (4.63) | 41.13 (5.56) | 36.21 (1.82) | 32.47 (1.01) | 36.27 (1.82) | 40.78 (5.74) | 34.56 (2.00) | 33.38 (2.29) |
Tea Tree Oil | Terpinen-4-ol | |
---|---|---|
β (C.I. 95%) | β (C.I. 95%) | |
V % | −0.091 (−0.104; −0.079) p < 0.0001 | 0.094 (0.010; 0.178) p = 0.0279 |
TotM % | −0.080 (−0.090: −0.070) p < 0.0001 | 0.049 (0.008; 0.091) p = 0.020 |
ProgM % | −0.163 (−0.185; −0.141) p < 0.0001 | 0.017 (−0.043; 0.077) p =0.564 |
AR % | 0.100 (0.086; 0.114) p < 0.0001 | −0.089 (−0.237; 0.060) p = 0.239 |
pH value | −2.071 (−10.308; 6.166) p = 0.619 | 4.348 (−8.203; 16.899) p = 0.491 |
TTO (mg/mL) | TER (41.5 %) (mg/mL) |
---|---|
2 | 0.83 |
1.8 | 0.75 |
1.6 | 0.67 |
1.4 | 0.58 |
1.2 | 0.5 |
1 | 0.42 |
0.8 | 0.33 |
0.6 | 0.25 |
0.4 | 0.17 |
0.2 | 0.08 |
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