Saturday, January 25, 2020

Luteolin and Kaempferol From Cassia Alata

Luteolin and Kaempferol From Cassia Alata LUTEOLIN AND KAEMPFEROL FROM CASSIA ALATA, ANTIMICROBIAL AND ANTIOXIDANT ACTIVITY OF ITS METHANOLIC EXTRACTS ANEELA WAHAB, TAHIRA, SABIRA BEGUM, ANJUM AYUB, IFFAT MAHMOOD, TALAT MAHMOOD, AQEEL AHMAD  AND NIDA FAYYAZ Abstract Cassia alata also known as candlebush is a medicinally important plant. In the present investigation we are reporting the isolation and structure elucidation of two flavonoids kaempferol (1) and luteolin (2) isolated from methanolic extract of its beans through bioassay guided fractionation. The structure of isolated compounds were characterized by spectroscopic techniques such as EIMS, 1H-NMR and 13C-NMR. In this article we are also presenting the antibacterial, antifungal and antioxidant activity of the methanolic extract of its leaves (CA-L), stem (CA-S) and beans (CA-BN). All the extracts showed remarkable antibacterial and weak antioxidant activity whereas moderate antifungal activity was only found in stem (CA-S) and beans (CA-BN) extracts. Introduction Cassia alata (Synonym; Senna alata) belonging to the family Leguminosae and subfamily of Fabaceae, commonly known as seven golden candlesticks, and ringworm senna (Quattrocchi U., F.L.S., 2012). This plant is native to the West Indies, tropical America, found wild almost throughout India and Pakistan (Khare C.P., 2007). C. alata with golden blooms is a summer bloomer and a striking spring that last for several weeks but prefer cooler month for flowering (Ray A.B., et al., 2010, Krishnan M. K. S., 1992). This shrub may grow up to 3 meters tall with irregular, angled, glabrous branches. Flowers have bright yellow colour. It has long, membranous, dehiscent pods with 25 or more seeds per pod (Ross I.A., 2003, Bhattacharjee S.K., 2004). Cassia alata is widely used as traditional medicine in India and Southeast Asia ( Reezal I., et al., 2002 ). This plant is reported to possess insecticidal, anti-inflammatory, hydragogue, sudorific, diuretic, pesticidal properties. Fresh leaves juice is used for ring worm, snakebite, scorpion bite, skin diseases, impetigo, syphilis sores, itching, mycosis (washerman’s itch), herpes and eczema. Roots, leaves and flowers of this plant possess many biological properties such as antibacterial, antifungal, anti-inflammatory, antitumor, expectorant and also useful in urinary tract problems (Quattrocchi U., F.L.S., 2012), asthma, bronchitis and constipation (Joshi S.G., 2000). The ethyl acetate extract of C. alata leaves possess hypoglycaemic activity (Ray A.B., et al, 2010). This plant also has hepatoprotective property. The main constituents of C.alata are flavonoids, alkaloids, anthraquinone derivatives, tannins, sterols and triterpenes (Neharkar V.S., Gaikward K.G., 2011). The pr esent paper describe the isolation and characterization of kaempferol (1) and luteolin (2). Herein we are also reporting the antimicrobial and antioxidant activities of the methanolic extract of leaves, stem and beans of this plant. All the extracts showed significant antibacterial (Table 2) and weak antioxidant activity (Table 4). Antifungal activity (Table 3) was only observed in the extract of stem and beans. Experimental Materials and Methods General: Silica gel PF254 (Merk) was used for vacuum liquid chromatography (VLC). Thin layer chromatography (TLC) was performed on pre-coated silica gel F254 (Merck). Gel permeation chromatography was performed on sephadex LH-20 (Pharmcia). The EIMS (electron impact mass spectrometery) were scanned on Jeol-JMS HX-110 mass spectrormeter. The 1H and 13C-NMR (Nuclear Magnetic Resonance) spectra were recorded on a Bruker spectrometer operating at 300 and 75 MHz respectively. The chemical shift values are reported in à ¯Ã‚ Ã‚ ¤ (ppm) relative to SiMe4 (Tetra methyl silane) as an internal standard. The coupling constant (J) is given in Hz. Plant Material: The Cassia alata was collected from Karachi (Sindh) and identified by Mr. Ghulam Rasool. A voucher specimen (86464) has been deposited in the herbarium at Department of Botany, Faculty of Science University of Karachi, Sindh Pakistan. Extraction and Isolation: The air dried leaves (7 kg), stem (5 kg) and beans (5 kg) of Cassia alata were extracted repeatedly with methanol at room temperature. The solvent was evaporated under vacuum to give 2 kg crude extract of leaves (CA-L), 3 kg crude extract of stem (CA-S) and 750 g crude extract of beans (CA-BN). The dark greenish brown gummy crude extract of beans (CA-BN) was partitioned with ethyl acetate (EtOAc), water (discard) and n-butanol fractions. Each fraction was concentrated in vacuum to have 15 g EtOAc and 15 g n-butanol soluble fractions. The EtOAc soluble fraction was further partitioned with n-hexane to obtained n-hexane soluble fraction and n-hexane insoluble fraction. The n-hexane soluble fraction (14 g) was subjected to vacuum liquid chromatography (VLC) (n-hexane: n-hexane: EtOAc in order of increasing polarity) which furnished 22 fractions (Fr-1-Fr-22). The Fr-15 was subjected to reverse-phase column chromatography using sephadex column LH-20 (CHCl3;CHCl3:MeOH in order of increasin g polarity) which yielded 12 fractions (Fr-15-1-Fr-15-12). The Fr-15-9 was further subjected to reverse phase column chromatography using sephadex column LH-20 (n-hexane:CHCl3:MeOH in order of increasing polarity) furnished 18 fractions (Fr-15-9-1-Fr-15-9-18). The Fr-15-9-10 eluted with n-hexane:CHCl3:MeOH (0.5:3:1.5) gave yellow amorphous powder which showed single spot on TLC using CHCl3: MeOH (9.2:0.8) as a solvent system was identified as kaempferol (1) (37 mg). The Fr-15-9-9 was further subjected to reverse-phase column chromatography using sephadex column LH-20 (n-hexane:CHCl3:MeOH in order of increasing polarity) which yielded 13 fractions (Fr-15-9-9-1 to Fr-15-9-9-13). The Fr-15-9-9-3 eluted with n-hexane:CHCl3:MeOH (0.5:3:1.5) showed single spot on TLC (CHCl3:MeOH, 9.2:0.8) appeared as yellowish powder and was identified as luteolin (2) (27 mg). Biological assay: Screening of antibacterial activity: The disc diffusion method (Bauer et al, 1966) was used to determine the antibacterial activity of methanolic extracts. 100 mg/ml of stock solution was prepared by dissolving extracts in DMSO. Sterile filter discs containing 10 à ¯Ã‚ Ã‚ ­l of stock solution were used for screening. The Mueller Hinton agar (Oxoid) plates were seeded with 24 hours old culture grown in Mueller Hinton broth (Oxoid). The prepared discs were placed onto the surfaces at different positions and plates were incubated at 37à ¯Ã¢â‚¬Å¡Ã‚ °C for 24 hours. Results were recorded by measuring the zone of inhibitions in mm. Gentamicin was used as a standard. Screening of antifungal activity: Antifungal activity was also determined by disc diffusion method (Bauer et al, 1966) as above. Briefly, a small amount of culture was transferred to 2-3 ml distilled water or normal saline in a screw capped tube with few glass beads (1 mm in diameter) and vortexes for 5-10 minutes to make a homogeneous suspension of fungal culture. Sabouraud dextrose agar (SDA) plates were seeded with this suspension. Sterile filter discs containing 10 à ¯Ã‚ Ã‚ ­l of stock solution were placed onto the surfaces at different positions. Plates were incubated at room temperature for 1 week. Results were recorded by measuring the zone of inhibitions in mm. Gresiofulvin was used as a standard. Determination of minimum inhibitory concentration (MIC): MIC of methanolic extracts were determined by the disc diffusion method ( Bauer et al, 1966). Sterile discs containing different concentrations of samples varying from 0.98 to 1000 à ¯Ã‚ Ã‚ ­g per disc were prepared. The MIC of those extracts showing maximum zone of inhibition against microorganism were calculated ( Table 2 ). Antioxidant activity: Antioxidant activity was determined by using the method described by Lee et al. (1998). 1,1-diphenyl-2-picrylhydrazyl (DPPH) was prepared in ethanol (300  µM). 10  µL of each extract and 90 ÃŽ ¼L solution of stable radical, 1,1-diphenyl-2-picrylhydrazyl (DPPH) was added in 96 well micro titer plates and incubated at 37 º C for 30 minutes. Absorbance was measured at 515 nm by using a spectrophotometer. Percent inhibition of radicals by treatment of test sample was determined by comparison with a DMSO treated control group. % Inhibition = (absorbance of the control-absorbance of the test sample) x 100 Absorbance of the control Ascorbic acid was used as standard control. The EC50 value calculated denotes the concentration (in ug/ml) of sample required to scavenge 50% of DPPH Characterization of Kaempferol (1) Yellow amorphous powder. 1H-NMR à ¯Ã‚ Ã‚ ¤ (300 MHz, CD3OD): 8.09 (2H, d, J = 8.7 Hz, H-2’, 6’), 6.91 (2H, d, J = 8.7 Hz, H-3’, 5’), 6.43 (1H, d, J = 1.8 Hz, H-8), 6.19 (1H, d, J = 1.8 Hz, H-6). EIMS m/z: 286 [M]+. 13C-NMR (see Table 1). All data were identical with that of reported in literature (Hadizadeh F., et al, 2003, Gangwal A., et al, 2010). Characterization of Luteolin (2) Yellow amorphous powder. 1H- NMR à ¯Ã‚ Ã‚ ¤ (300 MHz, CD3OD): 7.39 (1H, dd, J = 9.0, 1.8 Hz, H-6’) ,7.36 (1H, d, J = 1.8 Hz, H-2’), 6.88 (1H, d, J = 9.0, Hz, H-5’), 6.53 (1H, s, H-3), 6.43 (1H, d, J = 1.8 Hz, H-8), 6.19 (1H, d, J = 1.8 Hz, H-6). EIMS m/z: 286 [M]+. 13C-NMR (see Table 1). All data were identical with that of reported in literature (Saeidnia S., et al, 2009). Results and discussion: The phytochemical investigation of the methanolic extracts of Cassia alata beans resulted in the isolation of kaempferol (1) and luteolin (2). Compound (1) showed molecular ion peak at m/z 286 having molecular formula C15H10O6. Its 1H-NMR spectrum showed the characterstic peak of H-2’ and 6’ as a doublet at à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  Ãƒ ¯Ã¢â€š ¬Ã‚ ¸Ãƒ ¯Ã¢â€š ¬Ã‚ ®Ãƒ ¯Ã¢â€š ¬Ã‚ °Ãƒ ¯Ã¢â€š ¬Ã‚ ¹Ãƒ ¯Ã¢â€š ¬Ã‚  with ortho coupling of 8.7 Hz whereas H-3’ and 5’ with similar ortho coupling appeared at à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  6.91 as a doublet.1H-NMR spectrum of 1 further displayed signals of aromatic protons as a doublet at à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  Ãƒ ¯Ã¢â€š ¬Ã‚  6.19 (H-6) and at à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚   6.43 (H-8) showing meta coupling of 1.8 Hz. The EIMS spectrum of compound (2) is similar to (1) having same molecular mass (m/z 286) and formula (C15H10O6). In the 1H-NMR spectrum of 2 characterstic peak of H-3 appeared at à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  6.53 as a singlet. Other important signals observed at à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  6.88 (d, J = 9.0, Hz, H-5’), à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  7.36 (d, J = 1.8 Hz, H-2’) and à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  7.39 (dd, J = 9.0, 1.8 Hz, H-6’). The aromatic protons H-6 and H-8 showed same à ¯Ã‚ Ã‚ ¤Ãƒ ¯Ã¢â€š ¬Ã‚  and J value as in compound 1. The 13C-NMR spectrum (Table 1) of both compounds 1 and 2 displayed signals of nine quaternary and six methine carbons . All the 13C assignments are in agreement with the reported data (Gangwal A., et al, 2010, Saeidnia S., et al, 2009). The results of antibacterial activity indicated that all the methanolic extracts of C. alata (CA-L, CA-S and CA-BN) have potential to kill various pathogenic gram+ve and gram-ve bacteria (Table 2), whereas good antifungal activity was observed in CA-S and CA-BN extracts against Fusarium specie (Table 3). All the extracts (CA-L, CA-S and CA-BN) showed less than 50% inhibition of DPPH radicals in antioxidant activity (Table 4). CONCLUSION: The known flavonoids kaemferol (1) and luteolin (2) were isolated from the methanolic extracts of C. alata beans. The structure of the isolated compounds were elucidated by various spectroscopic techniques. Pharmacological investigations have indicated that all the extracts (CA-L, CA-S and CA-BN) of this plant possess significant antimicrobial and weak antioxidant activity. References: Bauer, A.W., Kirby, W.M.M., Sherris, J.C., Turck, M. (1966). Antibiotic susceptibility testing by a standardized single disk method. American Journal of Clinical Pathology, 45, 493–496. Bhattarchrjee, S.K. and Michael,A.M. (2004). Hand Book of Medicinal Plants. Pointer Publishers Jaipur 302003 (Raj), India, pp. 77-78. Gangwal, A., Parmar, S.K., Sheth, N.R. (2010). Vol. 2(1). Triterpenoid, flavonoids and sterols from Lagenaria siceraria fruits. Scholars Research Library. pp. 307- 317. Hadizadeh, F., Noaman, K., Hossein, H., Randa, K.A. (2003). Kaempferol from Saffron Petals. Iranian Journal of Pharmaceutical Research. pp. 251-252. Joshi, S.G. (2000). Medicinal Plants. Oxford and IBH publishing Co.Pvt. Ltd, New Delhi, Calcutta, India, pp. 117. Khare, C.P. (2007). Indian Medicinal Plants.Springer.New Delhi, India, pp.126. Krishnan, M.K.S. (1992). Vol.3. The Wealth of India. Council of Scientific and Industrial Research New Delhi, India, pp. 328. Lee, S. K., Zakaria, H., Chuyng, H. L., Kuyengl, L.,Games, E. J. C., Mehta, R. J., Kinghorn, D., and Pezzuto, J. M. (1998). Evaluation of the antioxidant potential of natural products.Combinatorial Chemistry and High Throughput Screening.1: 35-4 Neharkar, V.S., Gaikwad, K.G. (2011). Vol. 2(1). Hepatoprotective activity of Cassia alata (Linn.) leaves against Paracetamol-induced hepatic injury in rats. Research Journal of Pharmaceutical, Biological and Chemical Sciences: pp. 783-788. Quattrocchi, U., F.L.S. (2012). Vol.5 R-Z: CRC World Dictionary of Medicinal and Poisonous Plants. CRC Press Taylor Francis Group Boca Raton New York, USA, pp. 236-237. Ray, A.B., Chansouria, J.P.N. and Hemalatha, S. (2010). Medicinal Plants: antidiabetic and Hypoglycaemic Activities. ibdc Publishers Lucknow, India, pp. 95. Ross, I.A. (2003). vol.1. Medicinal Plants of the World. Humana Press, Totowa, New Jersey, pp. 165-166. Reezal, I., Somchit, M. N. and Abdul Rahim, M. (2002). Vol.1. In vitro Antifungal Properties of Cassia alata (GELNGGANG BESAR). Proceedings of the Regional Symposium on Environment and Natural Resources. pp. 654-659. Saeidnia, S., Yassa, N., Rezaeipoor ,R., Shafiee, A., Gohari, A. R., Kamalinejad, M., Gooderzy, S. (2009). Vol. 17(1). Immunosuppressive principles from Achillea talagonica, an endemic species of Iran. Journals.tums.ac.ir: pp. 37-41. Table 1. C13-NMR spectral data of kaempferol (1) and luteolin (2) in CD3OD (ppm) at 75 MHz Table 2. Antibacterial activity of different extracts of Cassia alata (zone of inhibition in mm) CA-L= Cassia alata Leaves, CA-S = Cassia alata Stem, CA-BN = Cassia alata Beans. Table 3. In Vitro Antifungal activity (zone of inhibition in mm) Table 4. Antioxidant activity of Methanolic extracts of C.alata

Friday, January 17, 2020

Main Issues and Trends That Affect Marketing

Main Issues and Trends that affect marketing management now days and how do they influence organizational planning. Marketing Management is a business discipline which is focused on the practical application of marketing techniques and the management of a firm's marketing resources and activities. Rapidly emerging forces of globalization have compelled firms to market beyond the borders of their home country making International marketing highly significant and an integral part of a firm's marketing strategy. Marketing managers are often responsible for influencing the level, timing, and composition of customer demand accepted definition of the term. In part, this is because the role of a marketing manager can vary significantly based on a business' size, corporate culture, and industry context. For example, in a large consumer products company, the marketing manager may act as the overall general manager of his or her assigned product. To create an effective, cost-efficient Marketing management strategy, firms must possess a detailed, objective understanding of their own business and the market in which they operate. In analyzing these issues, the discipline of marketing management often overlaps with the related discipline of strategic planning. The main issues and trends that affect marketing management are environmental problems, income gap, customer dissatisfaction, global competition, environmental deterioration, infrastructure neglect, economic stagnation, low labor skills and other issues. Some of these affect marketing management in a positive and negative manner, because they are problems and are considered opportunities. Marketing essentially is the creation and delivery of a standard of living to society. A market is a locus of trade: individuals or groups exchange anything, anywhere, anytime, to satisfy needs or wants. Most marketing managers have been satisfied analyzing their marketing plan using the classic Marketing Mix: Product, Price, Place, Promotion. With the advent of globalization in general, and the Internet in particular, marketing management must reevaluate these Four Ps, even converting to Four Cs to tackle the new challenges facing the old mix. I have realized that globalized market means that domestic companies can count on a much larger market potential for their goods and services; bad news is that they will face a greater number of competitors. Next, issue that I considered an issue that affect marketing management is environmental deterioration. Environmental deterioration presents countless opportunities to companies that can create more effective means of cleaning up the environment. Infrastructure neglect will provide huge opportunities for companies in the construction, transportation, and communication industries. Economic stagnation is another issue that is constantly affecting marketing management and the cause is its favoritism for companies that are good. Low labor skills are an issue and it promotes positive results in the business world because it challenges educational and training companies to design more effective programs for upgrading human skills. Last, although I have considered income gap issue as the first issue influencing organizational planning.

Thursday, January 9, 2020

Contract Management - 1251 Words

Contract Risk and Opportunities Richard S. Stainback Jr. LAW/531 June 27, 2011 Ben Waggoner Contract Risk and Opportunities Clarity of contract is an essential element to creating a workable and executable agreement. C-S and Span entered into a business contract that was ambiguous from the start. It used words like â€Å"ordinary† in terms of production. Terms like this are often up to interpretation and can be the failing point of an agreement. Legal Issues Present Breach of Contract under â€Å"Internal Escalation Procedure for Dispute†- C-S has failed to follow the agreed upon dispute resolution process in regards to the delays and quality concerns. C-S has tentatively threatened to terminate the contract in light of product delays†¦show more content†¦Management Responsibility (Span) – Span should revisit internal processes to see if there is a process that is slowing delivery of products to C-S. After the internal audit of processes the project management team should reach out to C-S and ask the same be done to ensure there are not any procedural delays present. Management Responsibility (C-S) – They should also internally audit there processes in regards to this project to ensure that the new management is onboard and understands the particulars of their responsibility to this project. Breach of Contract under substantial performance of contract- This measure allows for neither party to rescind the contract past 50% completion. While at the 60% point in the contract, Span has only delivered on 40% of its responsibility to C-S. It is understood that the delays are caused in part by both companies. This point is not a valid defense for Span and should be avoided in communication with C-S. Management Responsibility (Span) – Span needs to assign more manpower to this project to keep with the timeline. Management Responsibility (C-S) – C-S needs to express the concerns more effectively to Span and accept some responsibility due to the amount of changes requested. Dispute Resolution Methods Arbitration and Mediation- This method could be used by Span and C-S to resolve the contract dispute. It is less costly than traditional litigation. However this method does notShow MoreRelatedContract Creation and Management1199 Words   |  5 PagesContract Creation and Manage Law 531 Contract Creation and Management After completion of the Contract Creation and Management simulation the following legal issues were noted. There were problems with this contract from the beginning because the specifics of the contract were ambiguous from the start. 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Wednesday, January 1, 2020

Difference Between Density and Specific Gravity

Both density and specific gravity describe mass and may be used to compare different substances. They are not, however, identical measures. Specific gravity is an expression of density in relation to the density of a standard or reference (usually water). Also, density is expressed in units (weight relative to size) while specific gravity is a pure number or dimensionless. What Is Density? Density is a property of matter and can be defined as the ratio of mass to a unit volume of matter.  Its typically expressed in units of grams per cubic centimeter, kilograms per cubic meter, or pounds per cubic inch. Density is expressed by the formula: Ï  m/V where Ï  is the densitym is the massV is the volume What Is Specific Gravity? Specific gravity is a measure of density relative to the density of a reference substance. The reference material could be anything, but the most common reference is pure water. If a material has a specific gravity less than 1, it will float on water. Specific gravity is often abbreviated as sp gr. Specific gravity is also called relative density and is expressed by the formula: Specific Gravitysubstance Ï substance/Ï reference Why would someone want to compare the density of a substance to the density of water? Take this example: Saltwater aquarium enthusiasts measure the amount of salt in their water by specific gravity, where their reference material is freshwater. Saltwater is less dense than pure water but by how much? The number generated by a calculation of specific gravity provides the answer. Converting Between Density and Specific Gravity Specific gravity values arent very useful except for predicting whether or not something will float on water and for comparing whether one material is more or less dense than another. However, because the density of pure water is so close to 1 (0.9976 grams per cubic centimeter), specific gravity and density are nearly the same value so long as the density is given in g/cc. Density is very slightly less than specific gravity.