Pulp or Peel? Comparative Analysis of the Phytochemical Content and Selected Cosmetic-Related Properties of Annona cherimola L., Diospyros kaki Thumb., Cydonia oblonga Mill. and Fortunella margarita Swingle Pulp and Peel Extracts.

Fruit peels might be a valuable source of active ingredients for cosmetics, leading to more sustainable usage of plant by-products. The aim of the study was to evaluate the phytochemical content and selected biological properties of hydroglycolic extracts from peels and pulps of Annona cherimola, Diospyros kaki, Cydonia oblonga, and Fortunella margarita as potential cosmetic ingredients. Peel and pulp extracts were compared for their antiradical activity (using DPPH and ABTS radical scavenging assays), skin-lightening potential (tyrosinase inhibitory assay), sun protection factor (SPF), and cytotoxicity toward human fibroblast, keratinocyte, and melanoma cell lines. The total content of polyphenols and/or flavonoids was significantly higher in peel than in pulp extracts, and the composition of particular active compounds was also markedly different. The HPLC-MS fingerprinting revealed the presence of catechin, epicatechin and rutoside in the peel of D. kaki, whereas kaempferol glucoside and procyanidin A were present only in the pulp. In A. cherimola, catechin, epicatechin and rutoside were identified only in the peel of the fruit, whereas procyanidins were traced only in the pulp extracts. Quercetin and luteolinidin were found to be characteristic compounds of F. margarita peel extract. Naringenin and hesperidin were found only in the pulp of F. margarita. The most significant compositional variety between the peel and pulp extracts was observed for C. oblonga: Peel extracts contained a higher number of active components (e.g., vicenin-2, kaempferol rutinoside, or kaempferol galactoside) than pulp extract. The radical scavenging potential of peel extracts was higher than of the pulp extracts. D. kaki and F. margarita peel and pulp extracts inhibited mushroom and murine tyrosinases at comparable levels. The C. oblonga pulp extract was a more potent mushroom tyrosinase inhibitor than the peel extract. Peel extract of A. cherimola inhibited mushroom tyrosinase but activated the murine enzyme. F. margarita pulp and peel extracts showed the highest in vitro SPF. A. cherimola, D. kaki, and F. margarita extracts were not cytotoxic for fibroblasts and keratinocytes up to a concentration of 2% (v/v) and the peel extracts were cytotoxic for A375 melanoma cells. To summarize, peel extracts from all analyzed fruit showed comparable or better cosmetic-related properties than pulp extracts and might be considered multifunctional active ingredients of skin lightening, anti-aging, and protective cosmetics.

Moringa oleifera (drumstick tree)-nutraceutical, cosmetological and medicinal importance: a review.

Moringa oleifera Lam. (Moringaceae) is a species of tree with an increasing utility, occurring naturally mainly in Pakistan and northern India. M. oleifera is currently cultivated in Africa, South America, Asia and the Middle East. The usage of its leaves, seed oil, bark, fruits, flowers and roots has positive opinions of FDA (American Food and Drug Administration), EFSA (European Food Safety Authority) and CosIng (Cosmetic Ingredients database). The chemical composition of M. oleifera is dominated by: proteins (consisting mainly of amino acids such as arginine or serine), fatty acids (omega-3 and omega-6), vitamins (vitamin A, B and C and tocopherols), mineral salts (including several bioelements, such as calcium, magnesium, sodium, and potassium), valuable polyphenolic compounds from the group of phenolic acids (e.g., gallic acid, ferulic acid) and flavonoids (e.g., myricetin, rutoside, and kaempferol). The raw materials show antioxidant, hepatoprotective, anti-inflammatory and antimicrobial properties. Dietary supplements and alimentary products containing M. oleifera are recommended as health-promoting and "novel food" preparations. The main purpose of this work was a review of the latest scientific literature on M. oleifera, with particular emphasis on the studies focusing on its chemical composition, biological activity and safety. Moreover, the review tends to discuss the results of biotechnological studies using this material and the agronomical significance.