Multiple Biological Effects of Olive Oil By‐products such as Leaves, Stems, Flowers, Olive Milled Waste, Fruit Pulp, and Seeds of the Olive Plant on Skin

Abstract

As olive oil production increases, so does the amount of olive oil by-products, which can cause environmental problems. Thus, new ways to utilize the by-products are needed. In the present study, five bioactive characteristics of olive oil by-products were assessed, namely their antioxidant, anti-bacterial, anti-melanogenesis, anti-allergic, and collagen-production-promoting activities. First, the extracts of leaves (May and October), stems (May and October), flowers, olive milled waste, fruit pulp and seeds were prepared using two safe solvents, ethanol and water. According to HPLC and LC/MS analysis and Folin-Ciocalteu assay, the ethanol extracts of the leaves (May and October), stems (May and October) and flowers contained oleuropein, and the ethanol extract of the stems showed the highest total phenol content. Oleuropein may contribute to the antioxidant and anti-melanogenesis activities of the leaves, stems, and flowers. However, other active compounds or synergistic effects present in the ethanol extracts are also likely to contribute to the anti-bacterial activity of the leaves and flowers, the anti-melanogenesis activity of some parts, the anti-allergic activity of olive milled waste, and the collagen-production-promoting activity of the leaves, stems, olive milled waste and fruit pulp. This study provides evidence that the by-products of olive oil have the potential to be further developed and used in the skin care industry.

Bioavailability of Bioactive Molecules from Olive Leaf Extracts and its Functional Value

“…Moreover, European Food Safety Authority (EFSA) has recently accepted the olive leaf aqueous extract as a safe product and, therefore, the olive leaf extract could be used as food additive. In fact, olive leaf extract contain many potentially bioactive compounds that may have antioxidant, antihypertensive, antiatherogenic, antiinflammatory, anticancer, hypoglycemic, and hypocholesterolemic properties (De Marino et al, 2014;Fakhraei et al, 2014;Olmez et al, 2015;Kishikawa et al, 2015).…”

The Potential of Triterpenoids from Loquat Leaves (Eriobotrya japonica) for Prevention and Treatment of Skin Disorder

“…The assay for measuring the promotion of skin collagen synthesis was described by Kishikawa et al [41]. Adult NHDF cells (Lonza, Tokyo) were routinely maintained in 10% FBS and 1% antibiotic-antimycotic (Invitrogen) in Dulbecco’s modified Eagle’s medium (DMEM, Wako).…”

Chemical characterization and antioxidant properties of products and by‐products from Olea europaea L.

“…These by-products are pathogen-free and very rich in organic matter, in nutrients, and are also characterized by high levels of bioactive molecules (particularly, polyphenols), showing strong antimicrobial and phytotoxic activities and not easily biodegradable. For those bioactive properties, these by-products can be recovered and reused for the production of functional foods for human or animal consumption, as well as for diet supplements and cosmetics formulations (Gullón et al, 2018;Herrero et al, 2011;Kishikawa et al, 2015;Di Nunzio et al, 2018;Romero, Medina, Mateo, & Brenes, 2018;Sousa, Costa, Alexandre, & Prata, 2019;Vitali Čepo et al, 2018). For that reason, the use of the phenolic compounds extracted from olive by-products represents a great opportunity for the circular economy.…”