Mohammad Maroof Shah

Microbial ecology of anaerobic digesters: the key players of anaerobiosis.

Anaerobic digestion is the method of wastes treatment aimed at a reduction of their hazardous effects on the biosphere. The mutualistic behavior of various anaerobic microorganisms results in the decomposition of complex organic substances into simple, chemically stabilized compounds, mainly methane and CO2. The conversions of complex organic compounds to CH4 and CO2 are possible due to the cooperation of four different groups of microorganisms, that is, fermentative, syntrophic, acetogenic, and methanogenic bacteria. Microbes adopt various pathways to evade from the unfavorable conditions in the anaerobic digester like competition between sulfate reducing bacteria (SRB) and methane forming bacteria for the same substrate. Methanosarcina are able to use both acetoclastic and hydrogenotrophic pathways for methane production. This review highlights the cellulosic microorganisms, structure of cellulose, inoculum to substrate ratio, and source of inoculum and its effect on methanogenesis. The molecular techniques such as DGGE (denaturing gradient gel electrophoresis) utilized for dynamic changes in microbial communities and FISH (fluorescent in situ hybridization) that deal with taxonomy and interaction and distribution of tropic groups used are also discussed.

Phytoremediation potential of Arundo donax in arsenic-contaminated synthetic wastewater

The present study reports the potential of Arundo donax for phytoextraction of arsenic from synthetic wastewater. A. donax plants were grown under greenhouse conditions in pots containing a nutrient solution amended with increasing doses of As (0, 50, 100, 300, 600 and 1000 microg L(-1)) for 21 days in a completely randomized design. Shoot and roots dry matter production, growth parameters, arsenic and nutrient tissue concentrations were measured at the end of the experiment. Increasing As concentration in nutrient solution caused an increase in shoot and root biomass without toxicity symptoms in A. donax growing under a range of As concentration from 50 to 600 microg L(-1). Elevated oxidative stress was observed at As supplied level of 1000 microg L(-1). The As doses up to 600 microg L(-1) did not affect the growth of A. donax. It is suggested that A. donax plants may be employed to treat contaminated waters containing arsenic concentrations up to 600 microg L(-1).

Ethnobotanical appraisal and cultural values of medicinally important wild edible vegetables of Lesser Himalayas-Pakistan.

BackgroundThe association among food and health is momentous as consumers now demand healthy, tasty and natural functional foods. Knowledge of such food is mainly transmitted through the contribution of individuals of households. Throughout the world the traditions of using wild edible plants as food and medicine are at risk of disappearing, hence present appraisal was conducted to explore ethnomedicinal and cultural importance of wild edible vegetables used by the populace of Lesser Himalayas-Pakistan.MethodsData was collected through informed consent semi-structured interviews, questionnaires, market survey and focus group conversation with key respondents of the study sites including 45 female, 30 children and 25 males. Cultural significance of each species was calculated based on use report.ResultsA total of 45 wild edible vegetables belonging to 38 genera and 24 families were used for the treatment of various diseases and consumed. Asteraceae and Papilionoideae were found dominating families with (6 spp. each), followed by Amaranthaceae and Polygonaceae. Vegetables were cooked in water (51%) followed by diluted milk (42%) and both in water and diluted milk (7%). Leaves were among highly utilized plant parts (70%) in medicines followed by seeds (10%), roots (6%), latex (4%), bark, bulb, flowers, tubers and rhizomes (2% each). Modes of preparation fall into seven categories like paste (29%), decoction (24%), powder (14%), eaten fresh (12%), extract (10%), cooked vegetable (8%) and juice (4%). Ficus carica was found most cited species with in top ten vegetables followed by Ficus palmata, Bauhinia variegata, Solanum nigrum, Amaranthus viridis, Medicago polymorpha, Chenopodium album, Cichorium intybus, Amaranthus hybridus and Vicia faba.ConclusionsPatterns of wild edible plant usage depend mainly on socio-economic factors compare to climatic conditions or wealth of flora but during past few decades have harshly eroded due to change in the life style of the inhabitants. Use reports verified common cultural heritage and cultural worth of quoted taxa is analogous. Phytochemical analysis, antioxidant activities, pharmacological applications; skill training in farming and biotechnological techniques to improve the yield are important feature prospective regarding of wild edible vegetables.

Plants as Useful Vectors to Reduce Environmental Toxic Arsenic Content

Arsenic (As) toxicity in soil and water is an increasing menace around the globe. Its concentration both in soil and environment is due to natural and anthropogenic activities. Rising arsenic concentrations in groundwater is alarming due to the health risks to plants, animals, and human beings. Anthropogenic As contamination of soil may result from mining, milling, and smelting of copper, lead, zinc sulfide ores, hide tanning waste, dyes, chemical weapons, electroplating, gas exhaust, application of municipal sludge on land, combustion of fossil fuels, As additives to livestock feed, coal fly ash, and use of arsenical pesticides in agricultural sector. Phytoremediation can be viewed as biological, solar-driven, pump-and-treat system with an extensive, self-extending uptake network (the root system) that enhances the natural ecosystems for subsequent productive use. The present review presents recent scientific developments regarding phytoremediation of arsenic contaminated environments and its possible detoxification mechanisms in plants.

Optimization of DNA extraction from seeds and fresh leaf tissues of wild marigold (Tagetes minuta) for polymerase chain reaction analysis.

Tagetes, a genus of flowering marigolds in the family Asteraceae (Compositeae), is reported to be a medicinal plant with hypotensive, spasmolytic, anti-inflammatory, antimicrobial, and antifungal properties. Tagetes minuta characteristically contains high concentrations of essential oils, flavonoids, polyphenols, and polysaccharides that interfere with DNA, causing erroneous or no PCR products. We tested and modified various standard protocols in an effort to isolate high-quality DNA from different plant tissues of T. minuta. We used sun-dried, shade-dried and fresh-leaf tissues, as well as seeds for DNA analysis. The DNA obtained from seeds and fresh-leaf tissues with a modified cetyltrimethylammonium bromide buffer protocol was of good quality, with no colored pigments and contaminants. We were able to obtain good quality DNA from fresh leaf tissues without using liquid nitrogen. A relatively large amount of DNA was also extracted from the sun- and shade-dried tissues, but its quality was not as good as that from seeds. The DNA extracted from seeds and fresh leaves was successfully amplified by PCR using arbitrary RAPD primers. The same protocol will probably be useful for extracting high-molecular weight DNA from other plant materials containing large amounts of secondary metabolites and essential oils.

Ethnobotanical and antimicrobial study of some selected medicinal plants used in Khyber Pakhtunkhwa (KPK) as a potential source to cure infectious diseases

BackgroundPresent investigation deals with antimicrobial screening of ten medicinally important plants used by the inhabitants of district Haripur, Khyber Pakhtunkhwa (KPK) for different infectious diseases.MethodsAqueous, n-hexane and ethanolic extracts of each plant were tested for their antimicrobial activity against both Gram positive and Gram negative strains of bacteria, as well as strain of yeast. Agar well diffusion and broth dilution methods were used to determine the antimicrobial activity of different plant extracts.ResultsThe results indicated that all plants exhibited antimicrobial activity against one or more test pathogens. Interestingly, extracts of three plants showed strong and broad spectrum activity as compared to rest of the extracts which demonstrated the moderate activity. On the whole ethanolic extracts exhibited maximum antimicrobial effect than their corresponding aqueous and n-hexane extracts, when compared with standard antibiotics i.e., Streptomycin and Tetracycline. Among various extracts, only ethanloic extract of Azadirachta indica and aqueous and ethanolic extracts of Eucalyptus globulus and Bergenia ciliata and ethanolic extract of Punica granatum were found to have potentially promising activity against test microorganisms.ConclusionDifferent plant extracts show promising antimicrobial activity justifying their usage in traditional medicines. This study will be continued to identify more plants with potential antimicrobial components.

Transcriptomic responses of selected genes against chromium stress in Arundo donax L.

ABSTRACT Recently, giant reed (Arundo donax L.) has emerged as a useful bioresource capable of coping under harsh abiotic stress conditions produced by exposure to heavy metals, drought and salinity as evidenced by significant biomass production. The current study was undertaken to determine the expression of critical genes involved in resisting oxidative stress and maintaining normal cellular functions. The critical genes examined included glutathione reductase (GR) that prevents oxidative damage of membranes, carotenoid hydroxylase (CR), transcription factor (bHLH) and amidase involved in biosynthesis of indole-3-acetic acid following exposure to chromium (Cr) stress at concentrations of 0, 33.5, 67, 133 or 268 mg/L in giant reed. The S19 gene was used as internal control. It was not possible to extract RNA from severely stressed giant plant leaves at 133 and 268 mg/L Cr. Therefore, this investigation focused on gene expression in the presence of at 0, 33.5 or 67 mg/L Cr. Following Cr-mediated stress, gene expression of GR and CR was increased at 33.5 mg/L but reduced at 67 mg/L. The transcription factor, bHLH, gene expression remained unchanged. Amidase gene expression was elevated at 67 mg/L Cr. Data suggested that over expression of amidase and GR genes at high Cr exposure might increase growth and biomass of giant reed as well as enhance tolerance. These results indicated that giant reed tolerated the presence of Cr stress due to over expression of amidase and GR genes. It would appear that giant reed may serve a beneficial role for phytoremediation of Cr contaminated wastewater and soils at concentrations below 100 mg/kg.

Effective adsorption of cationic dye from aqueous solution using low-cost corncob in batch and column studies

Dye effluents and their degradation products disrupt the aquatic ecosystem functioning. Corncob was used as a low-cost biosorbent for decolorization of methylene blue (MB) dye. Batch and fixed-bed ...

Comparisons of DNA marker-based genetic diversity with phenotypic estimates in maize grown in Pakistan

We compared DNA-based genetic diversity estimates with conventional estimates by investigating agronomically important traits in maize grown in the northwestern region of Pakistan. RAPD markers were used to characterize 10 commonly cultivated maize genotypes. The same material was tested for phenotypic variation of quantitative traits using replicated field trials. The genetic distances between pairs of genotypes using RAPD data were used to generate a similarity matrix and to construct a phenogram. Statistical analyses were carried out on the data obtained from field trials of all maize genotypes for days to 50% tasseling, days to 50% silking, plant height, ear height, grain yield, grain weight per cob, and ear length. Analysis of variance and single degree of freedom contrasts were performed on morphological data to examine the relationship between molecular-based clusters and agronomic traits. A molecular marker-based phenogram led to the grouping of all genotypes into four major clusters, some of which were distantly related. These clusters contained one to four genotypes. Analysis of variance showed significant variations among all genotypes for agronomic traits. The single degree of freedom contrasts between groups of genotypes indicated significant differences for most traits. Pair-wise comparisons between clusters were also significant. The two types of data correlated well, providing an opportunity for better choices for selection.

A phytotoxin Solanapyrone-A downregulates calcium-dependent protein kinase activity in potato.

We previously demonstrated that alternaric acid, a host-specific toxin produced by the plant pathogenic fungus Alternaria solani, in the presence of Ca(2+) and Mg(2+), stimulated in vitro phosphorylation of His-tagged calcium-dependent protein kinase 2 from potato cultivar Rishiri (RiCDPK2). Herein, we report that Solanapyrone-A (SpA), a non-host-specific toxin produced by A. solani, inhibited the phosphorylation of RiCDPK2 in the presence of Ca(2+) and Mg(2+). However, SpA stimulated RiCDPK2 phosphorylation in the absence of these cations. Based on the current findings, we suggest that RiCDPK2 may mediate SpA-induced signaling independent of Ca(2+) and Mg(2+), leading to a compatible interaction between potato and A. solani.