Plant Extracts as Alternative Additives for Sperm Preservation

Abstract

Sperm preservation is a crucial factor for the success of assisted reproductive technology (ART) in humans, livestock, and wildlife. Irrespective of the extender and the storage conditions used, semen handling and preservation negatively affect sperm quality. Moreover, oxidative stress, which often arises during semen storage, significantly reduces sperm function and compromises the sperm fertilizing ability by inducing oxidative damage to proteins, lipids, and nucleic acids. Plant extracts have recently emerged as a cheap and natural source of additives to preserve and enhance sperm function during semen storage. The present work provides an update on the use of these natural compounds as alternative additives for sperm preservation in 13 animal species, including humans. A detailed description of the effects of 45 plant species, belonging to 28 families, on sperm function during semen storage is presented. The plant material and extraction method employed, dosage, possible toxic effects, and antimicrobial properties are provided.

Keywords: antioxidants; artificial insemination; cryopreservation; herbal pharmacognosy; oxidative stress; phytotherapy; plant extract; semen storage; spermatozoa.

Figure 1

(A) Plant families (N = 28) and species (N = 45) overviewed in the present work. (B) Number of plant species tested in the spermatozoa from different animal species.

Figure 2

Positive effects of plant extracts on sperm parameters. The numbers within parentheses refer to the following plant species: Achillea millefolium (1), Albizia harveyi (2), Aloe vera (3), Argania spinosa (4), Aspalathus linearis (5), Camellia sinensis (6), Capparis spinosa (7), Ceratonia siliqua (8), Cyclopia intermedia (9), Cymbopogon citratus (10), Diospyros kaki (11), Echinacea purpurea (12), Entada abyssinica (13), Eurycoma longifolia (14), Foeniculum vulgare (15), Gynostemma pentaphyllum (16), Ilex paraguariensis (17), Lippia origanoides (18), Lolium perenne (19), Melaleuca alternifolia (20), Melissa officinalis (21), Moringa oleifera (22), Myrrhinium atropurpureum (23), Nigella sativa (24), Opuntia ficus-indica (25), Origanum vulgare (26), Phoenix dactylifera (27), Portulaca oleracea (28), Psidium guajava (29), Punica granatum (30), Rhodiola rosea (31), Salvia miltiorrhiza (32), Salvia officinalis (33), Salvia rosmarinus (34), Sambucus nigra (35), Schisandra chinensis (36), Syzygium aromaticum (37), Syzygium cumini (38), Thymus capitatus (39), Thymus munbyanus (40), Tribulus terrestris (41), Ugni molinae (42), Urtica dioica (43), Viscum album (44), Zingiber officinale (45).