Biological evaluation and semi-synthesis of Isolated compounds from (Syzygium aromaticum (L.) Merr. & Perry) Buds
- Authors: Sibusiso, Rali
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11352 , http://hdl.handle.net/10353/d1021140
- Description: Natural products play a fundamental role in modern drug discovery as they continue providing diverse bioactive lead compounds for new drug formulation. However, isolation of these valued compounds is problematic. On the other hand, the morbidity and mortality rates caused by non-communicable diseases are increasing with improved longevity. Thus, the study herein focused on the isolation of plant-derived compounds from Syzygium aromaticum and evaluated their biological properties. Syzygium aromaticum is a well-known plant which belongs to family Myrtaceae. Dried flower buds of S. aromaticum were subjected to sequential solvent extraction. The ethyl acetate extract (15.535 g) was subjected to column chromatography using a silica gel (0.063-0.200 mm) for isolation. This has led to the isolation of three distinct compounds that were identified as eugenol, maslinic acid (MA) and oleanolic acid (OA). The structural elucidation of these valued compounds was done using NMR, GC-MS, LC-MS, FT-IR and Mp. Further semi-synthesis of the oleanolic acid afforded acetate and ester OA-derived compounds with better solubility properties. All these compounds were evaluated for analgesic and anti-inflammatory properties. All tested compounds were administered at a dose of 40 mg/kg to both Wistar rats and Swiss mice. Significant (p<0.01) analgesic and anti-inflammatory properties are obtained for all compounds. The effects of eugenol in all experiment were better except in the thermal-induced pain or tail flick test. In the case of modified compounds, the formalin induced pain test disclosed that oleanane derived compounds confessed analgesic and anti-inflammatory effects better than OA, whereas, in tale flick test oleanolic acid proved superior analgesic effects compared to all its derivatives with the exception of the acetyl-derivative. Acute anti-inflammatory test showed that acetyl-derivatives were more active than other compounds. In conclusion, chromatographic techniques and semi-synthesise of oleanolic acid have resulted to several plant-derived compounds with analgesic and anti-inflammatory properties. The semi-synthesized compounds may serve as alternative drug candidates for new analgesic and anti-inflammatory drug formulation
- Full Text:
- Date Issued: 2014
- Authors: Sibusiso, Rali
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11352 , http://hdl.handle.net/10353/d1021140
- Description: Natural products play a fundamental role in modern drug discovery as they continue providing diverse bioactive lead compounds for new drug formulation. However, isolation of these valued compounds is problematic. On the other hand, the morbidity and mortality rates caused by non-communicable diseases are increasing with improved longevity. Thus, the study herein focused on the isolation of plant-derived compounds from Syzygium aromaticum and evaluated their biological properties. Syzygium aromaticum is a well-known plant which belongs to family Myrtaceae. Dried flower buds of S. aromaticum were subjected to sequential solvent extraction. The ethyl acetate extract (15.535 g) was subjected to column chromatography using a silica gel (0.063-0.200 mm) for isolation. This has led to the isolation of three distinct compounds that were identified as eugenol, maslinic acid (MA) and oleanolic acid (OA). The structural elucidation of these valued compounds was done using NMR, GC-MS, LC-MS, FT-IR and Mp. Further semi-synthesis of the oleanolic acid afforded acetate and ester OA-derived compounds with better solubility properties. All these compounds were evaluated for analgesic and anti-inflammatory properties. All tested compounds were administered at a dose of 40 mg/kg to both Wistar rats and Swiss mice. Significant (p<0.01) analgesic and anti-inflammatory properties are obtained for all compounds. The effects of eugenol in all experiment were better except in the thermal-induced pain or tail flick test. In the case of modified compounds, the formalin induced pain test disclosed that oleanane derived compounds confessed analgesic and anti-inflammatory effects better than OA, whereas, in tale flick test oleanolic acid proved superior analgesic effects compared to all its derivatives with the exception of the acetyl-derivative. Acute anti-inflammatory test showed that acetyl-derivatives were more active than other compounds. In conclusion, chromatographic techniques and semi-synthesise of oleanolic acid have resulted to several plant-derived compounds with analgesic and anti-inflammatory properties. The semi-synthesized compounds may serve as alternative drug candidates for new analgesic and anti-inflammatory drug formulation
- Full Text:
- Date Issued: 2014
Isolation, Characterisation, and biological activity evaluation of essential Oils of Cymbopogon validus (Stapf) Stapf ex Burtt Davy and Hyparrhenia hirta (L.) Stapf
- Authors: Rungqu, Pamela
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11354 , http://hdl.handle.net/10353/d1021283
- Description: Cymbopogon validus and Hyparrhenia hirta belong to the Poaceae botanical family. Both plants are used as thatching material; H. hirta is also used for weaving mats and baskets. In this study, we investigated the anti-inflammatory effects of C. validus and H. hirta essential oils on fresh egg-albumin induced edema on Wistar rats. To fully understand the chemically induced anti-inflammatory properties of these plants, we first analyzed the chemical composition of the essential oils. The essential oils were analyzed using gas chromatography-mass spectrometry (GC-MS). In C. validus, 13 compounds accounted for 74.3% of fresh leaves oil, 14 compounds 71.8% of dried leaves oil and 12 compounds 73.3% of flower oil were identified from the GC-MS Chromatogram. The percentage yields were as follows fresh leaves oil 2.2%, dried leaves oil 2.0% and flower oil 2.4% v/w respectively. Linalool (3.2-29.6%) and northujane (4.4-16.9%) were the dominant compounds found in the 3 oils analyzed. While, α-terpineol 37.5% and verbenone 13.5% was only found in the fresh leaf oil, this was absent in the dried leaves oil and the flowers oil of C. validus. In H. hirta, 25 compounds accounted for 68.1% of fresh leaves oil, 40 compounds 71.9% of dried leaves oil, 23 compounds 77.6% of fresh flowers oil and 18 compounds 80.1% of dried flowers oil were identified from the GC-MS Chromatogram. The percentage yields obtained from the different parts were 3.4% for fresh leaves oil, 2.8% for dried leaves oil, 2.8% for fresh flowers oil and 0.7% for dried flowers oil v/w respectively. Northujane (8.5-30.0%), diisooctyl phthalate (4.4-26.5%), phytone (1.1-10.4%) were the dominant compounds found in the 4 oils analyzed. While, dibutyl phthalate 26.9% was only found in the fresh flowers and was absent in the dried flowers oil. Moreover, caryophyllene oxide (1.7-9.6%) was found in fresh leaves and dried flowers oil of H. hirta. In vivo analysis revealed that the two essential oils displayed significant edema inhibition effect overtime. They displayed strong anti-inflammatory properties when compared to control group. However, the H. hirta essential oil was more effective than that of C. validus. Linalool, α-terpineol, and northujane extracted from C. validus and H. hirta essential oils might have contributed to the anti-inflammatory effects observed in Wistar rats. This study, confirms the anti-inflammatory properties of C. validus and H. hirta suggesting that they may be used in diseases related to anti-inflammation.
- Full Text:
- Date Issued: 2014
- Authors: Rungqu, Pamela
- Date: 2014
- Language: English
- Type: Thesis , Masters , MSc (Chemistry)
- Identifier: vital:11354 , http://hdl.handle.net/10353/d1021283
- Description: Cymbopogon validus and Hyparrhenia hirta belong to the Poaceae botanical family. Both plants are used as thatching material; H. hirta is also used for weaving mats and baskets. In this study, we investigated the anti-inflammatory effects of C. validus and H. hirta essential oils on fresh egg-albumin induced edema on Wistar rats. To fully understand the chemically induced anti-inflammatory properties of these plants, we first analyzed the chemical composition of the essential oils. The essential oils were analyzed using gas chromatography-mass spectrometry (GC-MS). In C. validus, 13 compounds accounted for 74.3% of fresh leaves oil, 14 compounds 71.8% of dried leaves oil and 12 compounds 73.3% of flower oil were identified from the GC-MS Chromatogram. The percentage yields were as follows fresh leaves oil 2.2%, dried leaves oil 2.0% and flower oil 2.4% v/w respectively. Linalool (3.2-29.6%) and northujane (4.4-16.9%) were the dominant compounds found in the 3 oils analyzed. While, α-terpineol 37.5% and verbenone 13.5% was only found in the fresh leaf oil, this was absent in the dried leaves oil and the flowers oil of C. validus. In H. hirta, 25 compounds accounted for 68.1% of fresh leaves oil, 40 compounds 71.9% of dried leaves oil, 23 compounds 77.6% of fresh flowers oil and 18 compounds 80.1% of dried flowers oil were identified from the GC-MS Chromatogram. The percentage yields obtained from the different parts were 3.4% for fresh leaves oil, 2.8% for dried leaves oil, 2.8% for fresh flowers oil and 0.7% for dried flowers oil v/w respectively. Northujane (8.5-30.0%), diisooctyl phthalate (4.4-26.5%), phytone (1.1-10.4%) were the dominant compounds found in the 4 oils analyzed. While, dibutyl phthalate 26.9% was only found in the fresh flowers and was absent in the dried flowers oil. Moreover, caryophyllene oxide (1.7-9.6%) was found in fresh leaves and dried flowers oil of H. hirta. In vivo analysis revealed that the two essential oils displayed significant edema inhibition effect overtime. They displayed strong anti-inflammatory properties when compared to control group. However, the H. hirta essential oil was more effective than that of C. validus. Linalool, α-terpineol, and northujane extracted from C. validus and H. hirta essential oils might have contributed to the anti-inflammatory effects observed in Wistar rats. This study, confirms the anti-inflammatory properties of C. validus and H. hirta suggesting that they may be used in diseases related to anti-inflammation.
- Full Text:
- Date Issued: 2014
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