Hibiscus macranthus

Hibiscus Macranthus is a herb from the Hibiscus genus of plants in the Malvaceae family; Macranthus refers to its species.^[1] This species has historical usage as an aphrodisiac and pro-vitality agent in men in the western province of Cameroon, and has its historical usage tied in with the herb Basella Alba.

2.1. Testosterone

An in vitro study using testes slices and investigating the traditional mixture of Hibiscus Macranthus with Basella Alba (in a 2:1 dry weight ratio) noted that methylene chloride was effective at increasing tesosterone production from the testes at 5, 10, and 50ug/mL while the methanol extract was highly efficacious at 50ug/mL but decreaesd at 100ug/mL.^[2] When the two herbs are tested in vitro on Leydig cells separately, Hibiscus Macranthus appears to increase testosterone slightly (nonsignificantly) 10ug/mL while decreasing testosterone 60% at 100ug/mL, suggesting that it is lesser active than Basella alba.^[3] Basella Alba at 0.1mg/mL outperformend 10ug/mL Hibiscus Macranthus, with most of its bioactives in 'Fraction B' which was terpenoids or sterols and a methylene chloride:methanol 97:3 v/v extract.^[3] 

This same plant preparation with Basella Alba and ratio has been administered to otherwise healthy adult rats (30mg/kg of the extract, correlating to 720mg/kg fresh plant weight) was given orally for 15 days with testing at days 7 and 15.^[4] This study noted up to 17% increased body weight (food given ad libitum, not reported whether it differed) and 60% larger seminal vesicles on day 15 with normal histological morphology but a greater concentration of spermatozoa. Serum testosterone was increased 90% above controls on day 7 and remained 80% higher on day 15.^[4]

The combination of Basella Alba and Hibiscus Macranthus appears to significantly increase testosterone in otherwise healthy mice, which deserves some replication. Basella Alba may be more of an active ingredient though, and the herbs have not been tested in isolation

All current studies are conducted by one research group, however

2.2. Estrogen

Currently, all studies on Hibiscus Macranthus and estrogen are highly confounded Aloe buettneri, Justicia insularis, and Dicliptera verticillata.^[5][6][7] The mixture has shown efficacy in increasing circulating estrogen levels in otherwise healthy 22-day old female rats,^[7] but the contribution of Hibiscus Macranthus to these effects is not known.

Confounded with other nutrients, no conclusions on Hibiscus Macranthus can be drawn

Currently, the extent of toxicological information of Hibiscus Macranthus is the study feeding this herb (alongside Basella Alba in a 2:1 ratio) to otherwise healthy rats, where 720mg/kg of dry plant weight daily (480mg/kg Hibiscus Macranthus) was not associated with any toxicological clinical signs of testicular histology.^[4]

Limited to no toxicological information currently