الفهرس 
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Abstract
General Summary
Phytochemical and Biological studies on Spondias mangifera (L.), Family Anacardiaceae
Family Anacardiaceae which comprises 81 genera and 800 species is located mostly in the tropics and subtropics worldwide but also extends into the temperate zone. Members of this family are used in traditional medicine in the treatment of many ailments. Genus Spondias comprises 18 species among which Spondias mangifera was selected to be our plant of choice since few reports could be traced in the literature concerning the chemical composition of this plant.
The main objective of this study was to investigate the antidiabetic activity of Spondias mangifera methanol leaves extract and its fractions. The biologically active fraction was subjected to in vivo testing of its biological activity followed by an in-depth phytochemical investigation to isolate the phytochemical compounds responsible for the biological activity.
This study was divided into three main chapters:
Chapter 1: Biological investigation of the methanol soluble extract of Spondias mangifera leaves, its subfractions along with the essential oils of three organs of Spondias mangifera, (family Anacardiaceae)
Chapter 2: Phytochemical study of the methanol soluble extract of Spondias mangifera leaves, (family Anacardiaceae)
Chapter 3: Essential oils of leaf, flower and fruit pericarp of Spondias mangifera
Chapter 1: Biological investigation of the methanol soluble extract of Spondias mangifera leaves, its subfractions along with the essential oils of three organs of Spondias mangifera, (family Anacardiaceae)
a- In vitro cytotoxic activity
Spondias mangifera methanol leaves extract and its five main fractions were tested on HepG2 cell line. Results revealed that the methanol extract and the five main fractions have no significant cytotoxic activity on HepG2 cell line, the DCM fraction possessed the highest activity at the tested concentrations compared to the other fractions and total extract. The observed IC50 of the total extract and the five fractions was >200 μg/ml compared to the
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standard Doxorubicin which has an IC50 of 2.2 μM, while compound (1) (Hydroxycitric acid lactone 1,6-dimethyl ester) showed a moderate cytotoxic activity against HepG2 cell line and MCF-7 cell line with IC50 31.5 μM and 19.27 μM respectively.
b- In vitro α-amylase inhibitory activity
Spondias mangifera methanol leaves extract, the five main fractions and compound (1) (Hydroxycitric acid lactone 1,6-dimethyl ester) were tested to determine their α-amylase inhibitory activity. Results revealed that the DCM fraction exhibited the highest inhibitory activity with IC50 73.03 μg/ml followed by 84.3, 116.8, 540.6, 964.8, >1000, 93.8 μg/ml for methanol part of aqueous residual fraction, aqueous residual fraction, butanol, total extract, n-hexane fractions and compound (1) (Hydroxycitric acid lactone 1,6-dimethyl ester) compared to the standard Acarbose having an IC50 of 34.71 μg/ml.
c- In vivo antidiabetic, antilipidemic and anti-obesity activities
The DCM fraction was tested for its antidiabetic, antilipidemic and anti-obesity activities on male Albino rats. The results revealed that the DCM fraction is more potent at dose (200 mg/kg b.w.) compared to (100mg/kg b.w.) and is nearly similar to the reference drug (simvastatin). A significant decrease in total cholesterol, triglycerides, LDL-cholesterol and blood glucose level by 50.0, 46.4, 68.7 and 46.0%, respectively was observed, we can also find that the HDL-cholesterol increased by 83.0% in male Albino rats treated with 200 mg/kg b.w. of the DCM fraction for 2 months. Furthermore, there is a significant decrease in their body weight compared to the hypercholesterolemic group. It can be concluded that the DCM fraction is more effective if given for 2 months at a dose of 200 mg/kg.
d- Investigation of the biological activity of the essential oils
- Antibacterial, anti-helicobacter and anti-mycobacterial activities
The essential oils prepared from Spondias mangifera leaves, flowers and fruits pericarps were tested for their antibacterial activity against Gram positive, Gram negative bacteria and fungi using the agar well diffusion method and MIC was determined; furthermore the anti-helicobacter activity and anti-mycobacterial activity were determined. Results revealed that the essential oil of the leaves showed a good antimicrobial activity against Methicillin‐Resistant Staphylococcus aureus (MRSA) and Salmonella typhymurium (zones of inhibition of 16.07 and 9.97mm, respectively), which is very comparable to the reference
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antibiotic gentamycin (zones of inhibition of 15.0 and 17.02mm, respectively). The leaf essential oil conferred the highest anti-mycobacterial effect in alamar blue assay when compared to the pericarp and flower essential oils (83.62% inhibition, MIC of 0.49 μg/ml) when compared with isoniazid (100% inhibition, MIC of 0.12μg/ml). Also, the leaf essential oil showed the highest activity against Helicobacter pylori (91.24% inhibition, MIC of 1.95μg/ml) as compared with clarithromycin (100% inhibition, MIC of 0.98μg/ml).
Chapter 2: Phytochemical study of the methanol soluble extract of Spondias mangifera leaves, (family Anacardiaceae)
This chapter was divided into two parts:
a- Phytochemical screening of Spondias mangifera leaves
Chemical screening of the powdered dried leaves of Spondias mangifera revealed the presence of flavonoids, carbohydrates, tannins, sterols, triterpenes and saponins with absence of anthraquinones and alkaloids.
b- Phytochemical study of Spondias mangifera leaves
The methanol leaves extract of Spondias mangifera was subjected to liquid-liquid fractionation using different solvents of different polarities to afford five main subfractions. The obtained fractions were investigated to determine their α-amylase enzyme inhibitory activity. The biologically active DCM fraction was analyzed using a series of chromatographic techniques such as column chromatography, preparative TLC and preparative HPLC leading to the isolation of 7 compounds.
These compounds were elucidated trough 1H NMR, APT, and 2D-NMR including 1H- 1H COSY, HSQC, HMBC spectra after comparison with previously reported data and identified also by their ESI-MS.
The compounds were identified to be:
Compound (1): Hydroxycitric acid lactone 1,6-dimethyl ester
Compound (2): Hydroxycitric acid lactone 1-methyl ester (2a) & Hydroxycitric acid lactone (2b)
Compound (3): Scopoletin
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Compound (4): Hydroxycitric acid-1,5,6-trimethyl ester (4a) & Hydroxycitric acid lactone 1, 6-dimethyl ester (4b)
Compound (5): 5-O-Feruloyl quinic acid
Compound (6): Salicylic acid
Compound (7): Cinnamic acid
Chapter 3: Essential oils of leaf, flower and fruit pericarp of Spondias mangifera
Chemical profiling of the essential oils hydrodistilled from three organs of Spondias mangifera using GC/MS analysis
The hydrodistilled essential oils obtained from the leaves, flowers and pericarps of Spondias mangifera cultivated in Egypt were analyzed by GC/MS. The essential oils were yellow in color, having an aromatic odor and lighter than water. It was found that the leaves essential oils comprised 29 components (100%) while the flowers and pericarps contained 26 (100%) and 27 components (98.25%), respectively. Different classes had contributed to the composition of the oils; Sesquiterpene hydrocarbons represented the predominant components in the leaf and flower oils (57.69 and 61.22%, respectively), followed by oxygenated monoterpenes (30.38 and 28.79%, respectively). Meanwhile, the fruit oil was rich in long chain alkanes (51.52%), and fatty acid esters (25.67%). β-caryophyllene was found to be the most abundant component (49.91%) of the leaves, followed by α-terpineol (26.98%) then α-selinene (3.69%). Similarly, β-caryophyllene (53.29%) represented the major component of the flower essential oil, while in case of the pericarps, the most predominant component was nonacosane (25.25%).