Anti-aging potential of extracts from Sclerocarya birrea (A. Rich.) Hochst and its chemical profiling by UPLC-Q-TOF-MS.

BACKGROUND: Degradation of components of the extracellular matrix such as elastin and collagen by elastase and collagenase accelerates skin aging. Phytochemicals that inhibit the activity of these enzymes can be developed as anti-aging ingredients. In this study, an investigation of the anti-aging properties of Sclerocarya birrea (A. Rich.) Hochst (Marula) extracts was conducted in vitro with the aim of developing chemically characterized anti-aging ingredients. METHODS: Marula stems, leaves and fruits were extracted using methanol:dichloromethane (DCM) (1:1). The stems were later extracted using acetone, ethanol, methanol:DCM (1:1) and sequentially using hexane, DCM, ethyl acetate and methanol. The stem ethanol extract was defatted and concentrated. Elastase and collagenase inhibition activities of these extracts and Marula oil were determined using spectrophotometric methods. The chemical profile of the ethanolic stem extract was developed using Ultra-performance-liquid chromatography quadrupole-time-of-flight mass spectrometry (UPLC-Q-TOF-MS) with MassLynx software. Pure standards were used to confirm the identity of major compounds and were screened for anti-elastase and anti-collagenase activity. RESULTS: Marula stems extracts were the most active as they exhibited anti-elastase activity comparable to that of elafin (> 88%) and anti-collagenase activity as potent as EDTA (> 76%). The leaf extract had moderate anti-elastase activity (54%) but was inactive agains collagenase. Marula fruits and oil exhibited limited activity in both assays. The ethanolic extract of Marula stems was the most suitable based on its acceptability to the cosmetic industry and its anti-collagenase activity (99%). Defatting and concentration improved its antiaging activity and lowered the colour intensity. Six compounds have been tentatively identified in the chemical profile of the ethanolic extract of Marula stems of which four; quinic acid, catechin, epigallocatechin gallate and epicatechin gallate have been confirmed using pure standards. Epigallocatechin gallate and epicatechin gallate were as potent (p < 0.05) as EDTA at 5 µg/ml in the anti-collagenase assay. CONCLUSIONS: The ethanolic extract of Marula stems can be developed into an anti-aging ingredient as it exhibited very good in vitro anti-aging activity and its chemical profile has been developed. Epicatechin gallate and epigallocatechin gallate contribute to the anti-aging activity of Marula stem ethanol extract.

Protective Roles of Monsonia angustifolia and Its Active Compounds in Experimental Models of Alzheimer's Disease.

Alzheimer's disease (AD), a progressive neurodegenerative disorder, is characterized by the accumulation of neurotoxic ß-amyloid (Aß) peptides, which consequently affects cognitive decline and memory impairment. Current research on AD treatment is actively focusing on the prevention of neurotoxic Aß peptide accumulation. Monsonia angustifolia is reported to be consumed as an indigenous vegetable in Tanzania. In this study, we investigated the effect of the ethanol (EtOH) extract of M. angustifolia dried ground material on Aß production and spatial learning ability as protection against AD. The formation of Aß peptides was significantly reduced in HeLa cells stably transfected with the Swedish mutant form of ß-amyloid precursor protein (APPsw) after treatment with a 60% EtOH extract of M. angustifolia. We next examined the cognitive-improving effects of the EtOH extract in vivo. Tg2576 mice were treated with extract for 6 months and subjected to Morris water maze and novel object recognition tests. The results showed that the 60% EtOH extract of M. angustifolia significantly ameliorated behavioral deficits of the AD transgenic mice and reduced the level of insoluble Aß42 in the cerebral cortex and hippocampus. We further found that the 60% EtOH extract was effective for memory function recovery after shorter treatment (4 months). In addition, we isolated and identified several single compounds, justicidin A, 5-methoxyjusticidin A, chinensinaphthol, retrochinensinaphthol methyl ether, and suchilactone, from M. angustifolia and tested these compounds. Among them, justicidin A potently decreased the formation of Aß in APPsw-transfected cells. These data suggest that the 60% EtOH extract of M. angustifolia has the potential to be developed as a treatment of AD. Furthermore, justicidin A may contribute, at least partially, to the Aß alteration observed with the extract treatment.