This study deals with the exploration of new sources of natural antioxidants as well as developing effective antioxidants. It is a collaborative project between two universities, i.e. University of Sindh, Jamshoro, Pakistan and St. Cloud State University, U.S.A.; concerning with (i) investigation of antioxidant potential of some herbs and spices in Pakistan (ii) exploring antioxidant activity of flavonoids and their metal complexes after the complexation. Among the food scientists, natural origin is focus of powerful research for exploitation of newer sources of antioxidants. In extension of the investigations, in the first phase of the study, a number of botanical materials have been selected for evaluation of their antioxidant probability. Antioxidant potential of different spices and herbs such as Ajwain, Cinnamon, Coriander, Cumin, Fennel, Fenugreek and Kalonji was investigated. The extracts of herbs and spices were prepared by electrical shaking and soxhlet extraction methods. A number of solvents ranging from polar to non- polar were used as extractant. Total phenolic content and antioxidant potentional by 2, 2-diphenyl-1- picryhydrazyl radical (DPPH·) were used as the parameters to study the effectiveness of extraction medium, i.e. solvent. Among the extracts of herbs and spices, ethanolic extract was found to be richer in phenolics and antioxidant activity. Moreover, total phenolic content, total flavonoid content, reducing power, chelating activity and DPPH· scavenging activity parameters were used for investigation of their antioxidant potential. From the results it has been deduced that most of the herbal spice materials exhibited appreciable antioxidant power as; compared to previously exploited sources of natural antioxidants. The Kalonji was found to be the richest source of antioxidants among the herbs and spices analyzed. The order of spices in antioxidant potential is Kalonji> Fenugreek> Cinnamon> Ajwain> Coriander> Cumin> Fennel. The flavonoids compose one of the most ubiquitous groups of all plant phenolics and they are an important class of defense antioxidants. The organoleptic properties and human health scientific studies have revealed their importance in food for maintaining human health. Flavonoids reduce the risk of stroke and heart disease, protect against relieve hay fever, age- related vision disorders, asthma symptoms, sinusitis, alleviate inflammatory skin conditions, reduce inflammation in joints and muscles, common to rheumatoid arthritis, minimize menopausal hot flushes, shrink hemorrhoids, reduce varicose veins and battle viral infections. Transition metal ions participate in the initiation of free radical processes. The antioxidant action of flavonoids has been considered to be via two possible modes of action, metal chelation and radical scavenging. Radical scavenging arises by donation of hydrogen atom from the free hydroxyls on the flavonoids nucleus and other possible antioxidant mechanism for flavonoids is metal chelation through phenolic OH groups, preventing metal- mediated generation of free radicals and, accordingly, may shelter the potential biological target from oxidative stress. However, in the second phase of study, among the most common dietary and biologically active flavonoids, Quercetin was selected. In order to study the chelation mechanisms of flavonoids with metal ions that permit a better understanding of their complexation and antioxidant properties; it has been decided to synthesize their metal (Mn Co 2+ , Ni 2+ , Cu 2+ 2+ , and Zn2+ ) complexes. This phase of study also consist on the characterization and investigation of antioxidant activity and the microbial activity of flavonoid-metal complexes. The thermal analyses as TGA and DSC. UV–Vis, IR, 1H-NMR spectroscopic technique were also used to asses relevant interactions of flavonoids and metal ions, the chelation sites are dependence upon the complex structure on the metal/ligand ratio, the capacity of flavonoids in binding metal ions, and etc. The outcome largely depends on the experimental condition and the type of assay employed. The Job''s method (continual variation method) was used to validate the stoichiometric composition of the chelate for the synthesis of metal flavonoid complexes. The complex formation reactions of M(II) Resulted in the formation of 2:1 metal:ligand complexes quercetin respectively. 70+ % yield have been found in the method employed for their synthesis. UV–vis spectroscopy remained the main tool for structural analysis of flavonoids. Both of the complexes formation and subsequent electron transfer reactions of M(II) with these ligands were examined by using UV–vis spectrophotometry. The 1H-NMR results indicate that the quercetin coordinate with two M(II) ion by replacing two of its protons. The coordination sites and the binding property of quercetin have also been evaluated by IR spectroscopy, which shows the shift of bands due to the formation of complex. The antioxidant and antimicrobial potentional of the complexes were studied and compared with the activity of free quercetin. The quercetin-M(II) complexes are found more potent free radical scavenger than the parent quercetin ligands and play a prominent role in protecting from oxidative stress and microbial organisms. This study demonstrates antioxidant potential of herbs and spices, and shows that the antioxidant activity of a flavonoid may be enhanced through chelation with metals.
سید محامد علی عباسی افسوس ہے کہ دارالمصنفین کی مجلس انتظامیہ کے ایک معزز مخلص رکن جناب سید محامد علی عباسی ائی۔اے۔ایس ۱۵؍ ستمبر کو حیدرآباد میں وفات پاگئے، اِناﷲ وَ اِنا اِلَیہ رَاجِعُون، یہ اطلاع بہت تاخیر سے ان کے ہم وطن مولوی معین احمد علوی کاکوروی کے مکتوب گرامی سے ملی۔ ان کی زندگی حیدرآباد میں بسر ہوئی، دارالمصنفین کے بڑے قدرداں تھے، وہ نظام ٹرسٹ کے بہت بااثر رکن تھے، اس سے دارالمصنفین کو سالانہ گرانٹ دلائی اور اس کے لئے سفر کی صعوبت برداشت کرکے یہاں تشریف بھی لائے، بڑی خوبیوں کے مالک تھے، اونچے عہدوں پر فائز رہنے کے باوجود متواضع تھے، اپنی دیانت داری، حسن خدمت اور قابلیت کی وجہ سے نیک نامی حاصل کی اور بڑا عروج پایا، ان کی شخصیت باوقار، پرکشش اور قدیم شرافت و تہذیب کا دلکش نمونہ تھی، گزشتہ برس ہمدرد نگر میں ہونے والے دارالمصنفین کے جلسہ میں شرکت فرمائی، کیا خبر تھی کہ اس عالم ناسوت میں یہ ان سے آخری ملاقات ہے، اﷲ تعالیٰ مغفرت فرمائے اور اعزہ متوسلین کو صبر جمیل عطا کرے۔ (ضیاء الدین اصلاحی، نومبر ۱۹۸۹ء)
الملخص:
يقدم البحث رؤية نقدية بمنظار المقاربة الجمالية لأهم علامات التواصل الأيقوني –الصورة الفوتوغرافية، وبما تقدم من العرض عن مفهوم الصورة والكلمة بوصفهما وسط نسيجي مركب من العلامة الكلمية والصورية المتداخلة؛ لطبيعتهما السيميائية، وتداولها خطاباً يثري السرد ويغني الأحداث بتوجهه الدلالي، وبما تحمله الصورة من كفاءة وقوة بإيقاع النظام التواصلي، وما يكمن فيها من عناصر إفهاميه تمكّن من ادراك البعد المقصدي، وما لها من تأثير على القارئ وتوجيه لما فيه فائدة اجتماعية وإنسانية ونفسية، لذا فقد تمركزت محاور البحث على وصف الرسالة البصرية القائمة على اهم المحاور الكلاسيكة التي ابتدعها جاكبسون: المرسل (مبتدع النص)، المرسل اليه (المتلقي)، الرسالة (الصورة/ الكلمة)، والتركيز على اهم المرتكزات الثلاث (الصورة/ الكلمة) بوصفهما اشتغالا في المقاربة السيميولوجية، ضمن مجال البلاغة الرمزية ومدى تفوقهما في استحضار المعنى وقوفا عند الصورة الفوتوغرافية بالاعتماد على اهم أيقوناتها عبر بنية النص الصغرى والتي تجعلها اكثر استنطاقا بمهارة الفواعل الدرامية للصورة الفوتوغرافية عند تفكيك عناصرها واعادة تركيبها ضمن تكوينها الاوحد من اجل تقديم فعلا حركياً يضفي على الحكائية التوسع في السرد وتفاعلها مع بنية النص الكبرى، لذا يصبح القارئ امام شبكة متداخلة من مظاهر الحكي، فتشكل رؤية وبعداً فنياً يريد الكاتب إيصالها إليه بعدما اصبحت ظاهرة في نصه الروائي، لتختتم دراسة البحث حول اهم النتائج التي توصل إليها الباحث.
Viridans group streptococci (VGS), normal inhabitant of oral cavity, are involved in a number of oral and extra-oral diseases. Among oral diseases, dental caries is the most common public health problem throughout the world. The cariogenicity of oral streptococci is attributed to their acidogenic potential and glucan (extracellular polysaccharide) production. For the study, 552 subjects were selected at random from different localities of Karachi, Pakistan. The subjects were categorized as carious (29.5%, 163) and non-carious (70.5%, 389) with respect to prevalence of dental caries. The carious and non-carious subjects were further categorized with respect to sex and sociodemographic characteristics i.e. age (<20, 21-40, 41-60, 61-80 and 81-100 years), socioeconomic status (SES) based on monthly income (low, middle and high), marital status (married and unmarried), dietary habits [daily consumption of vegetable, meat, fruit, mixed diet (vegetable and meat), milk and milk products], use of tobacco products, use of betel quid products, chewing habits, use of tea and oral hygiene practices. Overall, the prevalence of dental caries was found higher in males (58.9%, 96/163) as compared to females (41.1%, 67/163). The same higher trend of prevalence of dental caries was observed for all categories with respect to sociodemographic characteristics except age where prevalence of dental caries was higher in female of 61-80 years age group. In the present study, 525 isolates belonging to 09 different species of VGS were obtained from oral cavity of 552 subjects. Streptococcus anginosus was the most abundant (53.5%) followed by S. mutans (14.5%), S. mitis (11.4%), S. uberis (6.5%), S. intermedius (4.6%), S. sanguinis (3.8%), S. oralis (3.4%), S. salivarius (1.3%) and S. acidominimus (1%). A preliminary screening to determine the glucan producing potential of all isolates of VGS was performed. Out of 525 isolates, 41.5% were glucan producers while 58.5% were glucan non-producers. Species-wise comparison revealed the highest frequency of S. mutans (80.3%) exhibiting glucan producing potential followed by S. oralis (61.1%), S. intermedius (50%), S. anginosus (36.7%), S. mitis (35%) and S. salivarius (14.9%). None of the isolates of S. uberis and S. acidominimus showed the ability to produce glucan. The frequency of isolates having glucan producing potential was observed higher from carious subjects (46.3%) as compared to non-carious subjects (39.1%). Whereas, species-wise distribution of isolates indicated that the prominent glucan producing species were S. sanguinis (100%, 3/3) and S. mutans (76%, 22/29) from carious and S. mutans (83%, 39/47) from non-carious subjects. The glucan producing potential of VGS was also estimated quantitatively. S. sanguinis produced largest quantity (276.2 mg mean, 206.2-324.6 range) followed by S. mutans (143.5 mg mean, 43.5-521.1 range). The antibiotic susceptibility pattern of 525 isolates of VGS was also evaluated against 24 antibiotics viz., penicillin, amoxicillin, cephalothin, cefazolin, cefotaxime, ceftazidime, imipenem, chloramphenicol, clindamycin, trimethoprim, azithromycin, erythromycin, clarithromycin, ciprofloxacin, levofloxacin, doxycycline, tetracycline, gentamicin, streptomycin, tobramycin, teicoplanin, vancomycin, rifampin and linezolid. The highest incidence of resistance (48.4%) was observed against erythromycin. Overall, 39.2% isolates were susceptible to all the antibiotics used for the study. The emergence of multi-drug resistance (MDR) was noted among remaining 60.8% isolates. The resistance rate was observed as 5.5% isolatesresistant to 1 antibiotic, 4% isolates to 2 antibiotics, 6.3% to 3, 3.2% to 4, 2.5% to 5, 5% to 6, 2.9% to 7, 2% to 8, 4.2% to 9, 1.7% to 10, 2.1% each to 11 and 16, 2.7% to 12, 6% to 13, 2.9% to 14, 4% to 15, 2% to 17, 0.4% each to 18, 21 and 24, 0.8% to 19 and 0.2% to 20 antibiotics. In the present study, the in vitro antibacterial activities of oil, aqueous infusion and aqueous decoction of clove buds (Eugenia caryophyllata) and aqueous infusion and aqueous decoction of miswak (Salvadora persica) were determined against isolates having glucan producing potential viz., S. anginosus (19), S. mutans (10), S. mitis (14), S. intermedius (10), S. sanguinis (10), S. oralis (10) and S. salivarius (07). The highest antibacterial activity was noted for clove oil as all the isolates were found susceptible. It exhibited strong antibacterial activity against S. mutans (20.2mm mean zone of inhibition±3.4SD) from carious subjects and S. sanguinis (17.7mm mean zone of inhibition ±1.1SD) from non-carious subjects. The aqueous decoction of clove buds exhibited the highest zone of inhibition against S. mutans obtained from carious subjects (16.8mm±3.4SD) followed by non-carious subjects (14.3mm±2.3SD). The aqueous infusion of clove buds showed the highest zone of inhibition against S. mutans isolated from carious (13.2mm±3.2SD) and non-carious (13.6mm±4.2SD) subjects. Aqueous infusion and aqueous decoction of miswak failed to inhibit the tested VGS. The MICs and MBCs of the clove oil, aqueous infusion and decoction of buds of clove against VGS was recorded as 5 – 0.625%, 5% and 5 – 2.5%, respectively. The effect of clove oil and aqueous infusion of miswak was also evaluated on glucan production. The VGS isolates producing large amount of glucan were selected for the study. The effects of different concentrations of clove oil (0.5%, 0.25%, 0.125%, 0.0625% and 0.0313%) and aqueous infusion of miswak (10%, 8%, 5%, 2.5%, 1.25% and 0.5%) was assessed for the synthesis of glucan. The different concentrations of herbs preparations exhibited varying degree of reduction in glucan production. Clove oil was more effective and reduced the formation of glucan to approximately 80% in a dose dependent manner.