The pomegranate, the scientific name ‘Punica granatum L.,’ is a fruit-bearing deciduous shrub that contains thousands of health benefits, as stated three times in the Holy Qur’an. The plant’s many applications prove its advantages as fruits that are beneficial to human beings. The term ‘pomegranate’ is the English name, while ‘al-Rumman’ or ‘al-Rummanah’ is Arabic (Munirah, 2011). In ancient times, the Old Testament of the Bible, the Jewish Torah, and the Babylonian Talmud describe the pomegranate as a divine fruit conferring forces of fertility, good luck, and abundance.
Punica granatum L. has a long history of use as a traditional or herbal medicine source. The fruit of the pomegranate has medicinal properties, including anti-inflammatory and antibacterial ones. For instance, skin and breast cancers are both inhibited by pomegranate seed oil due to its anti-inflammatory action. Punica granatum L. fruit is high in phenolic compounds with significant antioxidant activity, and the seed oil contains phytoestrogenic compounds. Pomegranate fruit and bark are used to treat intestinal parasites, dysentery, and diarrhea. The juice and seeds are used as a throat and heart tonic. The concoction of seeds and juice is also employed to treat hemorrhoids and avoid nose and gum bleeds. Punica granatum L. is now a fruit that not only entices the public’s attention but also draws research into its therapeutic properties and food industry. As a result of pomegranate’s possible medicinal and industrial use, plenty of research studies in this area have already been initiated. However, there has not been enough research on pomegranate’s antioxidant function.
Pomegranate (Punica granatum L.) is one of the earliest domesticated fruits known to people. It spreads from Central Asia to the Himalayas, Anatolia’s Eyalet, the Middle East, and the Mediterranean. Pomegranates are also grown in Arizona, California, and the Mediterranean. South Asia and Middle Eastern countries, including Kandahar and Afghanistan, are known for their high-quality pomegranates. Pomegranates are now grown in Saudi Arabia, Spain, Italy, Afghanistan, America, India, China, Russia, Uzbekistan, Morocco, and Greece, among other places.
Sugars, organic acids, polyphenols, flavonoids, anthocyanins, fatty acids, alkaloids, vitamins, and other metabolites are contained in different parts of the Punica granatum L. fruit and tree. The essential sugars found in the Punica granatum L. extract are glucose, fructose, sucrose, and maltose, while the vitamins are C, B1, B2, and beta-carotene. Malic acid, fumaric acid, oxalic acid, succinic acid, citric acid, and tartaric acid are only a few of the primary organic acids contained in Punica granatum L. Alkaloids present in pomegranate peel include ellagic acid, gallic acid, chlorogenic acid, cinnamic acid, protocatechuic hydroxy acid, hydroxybenzoic acid, caffeic acid, ferulic acid, coumaric acid, p-coumaric acid, and o-coumaric acid. The pomegranate’s bark can also yield pelletierine, isopelletierine, methylpelletierine, pseudopelletierine, punicalagin, punicalin, phloridzin, quercetin, and catechin. Luteolin, kaempferol, and narigenin are flavonoids present in glycoside forms in Punica granatum L.
Anthocyanin is the main compound in pomegranate that is responsible for color induction. Anthocyanin is a glycoside that releases a glucose molecule and aglycone ring, also known as the anthocyanidin, when broken down. The anthocyanins are derived from pelargonidin (orange and red colors), cyanidins (red and deep red colors), and delphinidins (blue and purple colors). Six anthocyanins are responsible for the red color of edible parts of Punica granatum L; these are 3,5-diglucoside delphinidin, 3-glycoside delphin, 3,5-diglucoside cyanidin, 3-glycoside cyanidin, 3,5-diglucoside pelargonidin, and 3-glycoside pelargonidin. The color of the fruit changes gradually as Punica granatum L matures; however, this pigment transformation is slow and increases only after the middle stage of maturation. The amount of di glucoside anthocyanins appears to be higher in the early development stages than the mono glucoside forms. However, the pattern reverses at the end of development and ripening. The proportion and shape of anthocyanins also vary depending on the cultivar.
The existence of antioxidants such as ascorbic acid and phenolic compounds such as punicalagin, punicalin, gallic acid, ellagic acid, and anthocyanins may be attributed to the antioxidant activity of pomegranate fruit. Fruit development affects these compounds, as the highest antioxidant activity was found in newly developed fruits after 20 days. The fruit’s antioxidant activity decreases because the amount of ascorbic and phenolic acids decreases as the fruit matures. Furthermore, the antioxidant activity of phenolic compounds and ascorbic acid differs among pomegranate plant varieties (Sarkhosh A, Zamani Z, Fatahi R, unpublished data).
More attention has recently been paid to the oil extracted from pomegranate seeds, especially its use in the industrial process and the provision of essential fatty acids. Saturated and unsaturated fatty acids account for the significant proportions of composite fatty acids. The predominant fatty acids in the most studied pomegranate cultivars are linolenic (74% to 88%) and linoleic acid (5 percent to 16 percent ). Besides, some fatty acids, including oleic acid, palmitic acid, stearic acid, palmitoleic acid, arachidonic acid, lauric acid, and caprylic acid, are found in various variants of Punica granatum L. According to studies, unsaturated fatty acids are the main components of lipids in sweet pomegranate fruit cultivars. Pomegranate seeds oil include the steroidal estrogens such as γ-tocopherol, 17-α-estradiol, stigmasterol, β-estriol sitosterol, and testosterone) and nonsteroidal compounds like campesterol and coumestrol.
Flowers, leaves, young shoots and root bark, fruit peel, and pomegranate sauce have all been used in the past. All parts of the Punica granatum L. fruit with many tannins have a robust astringent effect. Several infusions or decoctions of the plant flowers have been used in herbal medicine to treat simple diarrhea and vaginal discharge. This extract, along with pomegranate peel, is also commonly gurgled to alleviate pancreas inflammation. The fruit decoctions of Punica granatum L. are used to treat gallbladder disorders. The fruit contains abundant tannins, which explains the bitter taste. Its decoction also tends to be successful in treating common diarrhea, dysentery, and stomach problems. Pomegranate seed has low tannin content and is commonly used to treat women’s vaginal discharge and wound healing. The alkaloid substances in fresh or dried root barks or ethanol extracts of pomegranate are used to kill intestinal parasites. Because of its antibacterial and anti-inflammatory properties, it is also used in herbal medicine.
Pomegranate is identified as an antiparasitic fruit for both humans and livestock. Pomegranate peels have been used for centuries to treat common diarrhea and dysentery. Future research should focus on developing a natural antidiarrhea remedy from pomegranate peel for use in over-the-counter or prescription drugs. Since the juice and oil serve as a possible nutritional supplement in improving longevity and preventing heart disease and cancer, flavonoids present in the fruit have a powerful antioxidant function and inhibitory enzymes’ effects. Via inhibition of cycloxygenase and lipoxygenase eicosanoid enzymes, the extracted oil of pomegranate can effectively prevent prostaglandin or leukotriene development, increasing the use of oil or its derivatives as internal or external anti-inflammatory substances.
Pomegranates have led to the recent focus on using phytoestrogenic compounds in medicine to prevent and treat menopause, osteoporosis, and cardiovascular disease caused by cancer or decreased estrogen. These promising studies may raise the possibility of using pomegranate seed oil and juice for therapeutic purposes instead of the standard hormone replacement therapy (HRT) in postmenopausal women using internal and external phytoestrogen.