Passionvine, wild passion flower, maypop, apricot vine, Holy-Trinity flower, molly-pop, passion vine, pop-apple, granadilla, maycock, maracoc, maracock, white sarsaparilla
The family Passifloraceae contains more than 400 different species of plants, most of which are perennial vines (McGuire, 1999; Miroddi et al., 2013). P. incarnata is closely related to P. edulis, and research suggests that these two plants may share many properties (McGuire, 1999). P. edulis is cultivated for its seeds and its pulp (Crellin and Philpott, 1990). The fruit of P. edulis can be eaten alone or as part of a fruit salad and can be used to make jams (Crellin and Philpott, 1990).
Geographic Distribution and Habitat
The plant is native to southeastern North America (McGuire, 1999). It is the only member of its genus that is native to the temperate regions of North America; other plants in the genus Passiflora are native to the tropics and subtropics (McGuire, 1999). P. incarnata has been spread by humans to other places outside of its range to include the northeastern United States, Texas, Australia, Europe, and Hawaii (McGuire, 1999). It can be found on roadsides, in agricultural fields as a weed, and early successional habitats (McGuire, 1999).
P. incarnata is a perennial dicot and woody vine in the family Passifloraceae (McGuire, 1999; Ross, 1999; USDA). It can reach lengths of up to 25 feet long with many adventitious shoots (McGuire, 1999) and blooms from June to September (USDA). The flowers are often purple but can also be white in some cases (McGuire, 1999; USDA). The colorful petals, sepals, and reproductive organs of the flower combine to make it quite beautiful. The Passionflower is named for the passion of Jesus Christ (Ross, 1999). The thread-like structures are seen as a symbol for the crown of thorns He wore, the five stamens represent His wounds, the three stigmas are for the nails on the Cross, and the five petals and five sepals represent ten of the apostles (Ross, 1999). The fruit from this plant, a berry that appears a few months after flowering, is called a “maypop” (McGuire, 1999; Ross, 1999; USDA). This fruit is yellow and “about the size of a large oval hen’s egg” (USDA).
This plant usually relies on carpenter bees (Xylocopa spp.) for pollination and is considered a minor weed in agriculture (McGuire, 1999). The Gulf Fritillary (Agraulis vanillae) butterfly lays eggs on P. Incarnata. Extrafloral nectaries hold small amounts of food used by ants. P. incarnata is the larval host for Gulf Fritillary, Zebra Longwing, Crimson-patch longwing, Red-banded hairstreak, Julia butterfly, and Mexican butterfly.
Portion of the Plant Used
The fruits of this plant are edible and said to taste very good (McGuire, 1999).The leaves, stems, and flowers are also used in herbal medicine, but the leaves and stems are the parts of the plant that are most often used in this field (Dhawan et al., 2001; McGuire, 1999; Ross, 1999; Sarris et al., 2013).
Plants in the genus Passiflora have been traditionally used by many different groups of people worldwide (Miroddi et al. 2013). The flavorful fruit of P. incarnata has been consumed by people for some time, and McGuire argues that it has a use as a food crop (1999). This fruit was harvested and consumed by Native Americans historically and then by European settlers when they arrived to North America (McGuire, 1999). Traditionally, plants in the genus Passiflora have been used for the treatment of insomnia in Europe and as part of a sedative tea in North America (Miroddi et al. 2013). They have also seen use for their anti-spasmodic, anti-asthmatic, and sedative properties by people in Brazil, as both a narcotic and sedative in Iraq, and to treat insomnia, epilepsy, and other disorders in Turkey (Miroddi et al., 2013).
These plants have been used to treat hysteria, burns, and diarrhea, also P. incarnata Linneaus has even been used to help patients with opiate dependencies in India (Miroddi et al., 2013). P. incarnata L. has been used traditionally as a sedative and an anxiolytic for patients receiving anesthesia before operations in places all over the world (Aslanargun et al., 2012). It has also been used to make herbal teas for treating insomnia, mainly in children (Bremness, 1988).
Much of the research on P. incarnata has been conducted in recent years. Research has shown that the extracts from the leaves are the part of the plant most often used in herbal medicine (Sarris et al., 2013). A 2007 study that involved the cross-reference of the results from studies involving P. incarnata found that using extracts from the plant was not significantly effective for treating anxiety disorder (Miyasaka et al.). In contrast to this, later research by Dhawan et al. found that extracts from “leaves, stems, flowers, and whole plant exhibited anxiolytic effects at 100, 125, 200 and 300 mg/kg, respectively” (2001). They found no evidence of anxiolytic effects in the roots of the plants (Dhawan et al., 2001). Their results also found that the roots and flowers of P. incarnata act as natural adulterants by causing a significant increase in the anxiolytic dose and recommend that these parts of the plant are separated prior to other studies on the plant (Dhawan et al., 2001).
In a later study, Dhawan et al. further found that P. incarnata has higher anxiolytic effects than other members of the genus Passiflora (2001). Oral administration of P. incarnata has also been found to reduce anxiety for patients of outpatient surgeries without causing sedation by Movafegh et al. (2008). Aslanargun et al. found that the oral administration of P. incarnata Linneaus prevented an increase in anxiety prior to spinal anesthesia specifically (2012). In addition, drinking an herbal tea made from P. incarnata has been seen to act as a short-term sleep aid for people having trouble sleeping (Ngan and Conduit, 2011).
Biochemical and Physiological
A tri-substituted benzoflavone moiety (BZF) has been isolated from extracts of P. incarnata (Dhawan, 2003). Dhawan believes that it is this substance that is responsible for its properties important to herbal medicine (2003). This BZF has been linked with significant levels of reduced drug tolerance and dependency of addicting substances such as morphine, nicotine, and diazepam (Dhawan, 2003). In addition to this, research found this BZF to exhibit libido- and virility-enhancing properties in rats (Dhawan, 2003). Dhawan believes that this BZF acts as an aromatase-enzyme-inhibitor to free up hormones such as testosterone and estrogen that contribute to the well-being of the individual (2003). Research showed that administration of this compound prevented the decline in sex hormones that would normally be seen in individuals with chronic intakes of ethanol or nicotine (Dhawan, 2003). Other research has shown that P. incarnata and P. edulis contain alkaloids such as harman, harmine, hermol, and hermalol (Crellin and Philpott, 1990). These alkaloids are what the sedative effects of using these plants are believed to come from (Crellin and Philpott, 1990).
Research by Swamy and Ramesh suggest that extracts from P. incarnata could be used as an anticonvulsant (2011). They state that this is important because many anticonvulsants are difficult to obtain due to their expense (Swamy and Ramesh, 2011). Furthermore, Dhawan’s findings suggest that the extracts from the plant can be used as hormonal regulators (2003), and much of the research on the extracts anxiolytic properties suggest that this plant may be useful to alleviate anxiety (Aslanargun et al., 2012; Dhawan et al. 2001; Movafegh et al. 2008).
Side Effects, Interactions, and Contraindications
P. incarnata is classified as “generally recognized as safe” by the U.S. Food and Drug Administration and no cases of a lethal overdose have been reported (Burdock and Carabin, 2004; Miroddi et al., 2013). One case of toxicity has been reported, with the side effects in this case including nausea, vomiting, and drowsiness (Fisher et al. 2000). Bacchi et al. (2013) reported altered sexual behavior in male rats exposed to a commercial P. incarnata product in utero.
It has been reported that the usage of P. incarnata in one case resulted in negative side effects (Aslanargun et al., 2012; Fisher et al. 2000). In a case study by Fisher et al., one patient was found to experience serious negative side effects from using P. incarnata that included nausea, vomiting, and drowsiness (2000). Aslanargun et al. report that cases like these are very rare (2012). In their study, they found no negative side effects in patients from using this plant as an anxiolytic (Aslanargun et al. 2012).