The impact of heavy metal toxicity on the shoot and root lengths, total protein, fiber characteristics, moisture content and nutrient composition of spinach (Spinacia oleracea) was evaluated. Plants were grown in pots containing soil and treated with different concentrations (mg/kg) of lead (Pb; 300, 400 and 500), cadmium (Cd; 0.5, 1 and 1.5) and zinc (Zn; 250, 500, and 700) as well as mixtures of Cd and Pb (0.5/300, 1/400, 1.5/500), Cd and Zn (0.5/250, 1/500, 1.5/700), and Pb and Zn (300/250, 400/500, 500/700). Soil contaminated by long-term irrigation with wastewater containing heavy metals was simulated. An increase in concentrations of heavy metals both individually and as mixtures significantly (p < 0.05) reduced the growth parameters and nutrient contents of S. oleracea. The uptake patterns of heavy metals in mixtures showed antagonistic impacts on each other. The toxicities of the mixtures Cd and Pb, Cd and Zn as well as Pb and Zn were higher than those observed in separate heavy metal applications but less than their additive sums. The toxicity caused by individual heavy metals was the highest for Cd followed by Pb and Zn. The highest toxicity was observed in plants grown in soil contaminated by Cd and Pb.

Sulfur deficiency arising due to intensive cultivation, use of sulfur free fertilizers and reduction in atmospheric sulfur depositions has become a major issue limiting crop production in many parts of the world. Elemental sulfur could be a good source of available S, but its slow oxidation is a problem for its efficient use as a sulfur fertilizer. Main objective of the study was to assess the effect of organic amendments (OA) and elemental sulfur (ES) on microbial activities, sulfur oxidation and availability in soil. A laboratory incubation experiment was carried out for a 56 days period using two sulfur deficient alkaline soils. Organic amendments (OA), i.e., farmyard manure (FYM), poultry litter (PL) and sugarcane filter cake (SF), were applied (1% w/w) with or without elemental sulfur (ES) at 50 mg kg⁻¹. Application of ES alone or in combination with OA significantly increasedCO₂-C evolution, microbial biomass, and enzyme activities in the soils, except dehydrogenase activity (DHA) which was not affected by ES application. Combined application of OA and ES had a more pronounced effect on microbial parameters compared to ES or OA applied alone. Ratios of dehydrogenase activity-to-microbial biomass C and arylsulfatase activity-to-microbial biomass C were high in ES+FYM and ES+SF treatments, respectively. Elemental sulfur got sufficiently oxidized resulting in significant improvement in plant available S. Relatively more ES was distributed into C-bonded-S than ester bonded-S. Increase in sulfur availability in ES+OA amended soils was the combined function of sulfur oxidation and mineralization processes through improved microbial activity.

Continuous application of phosphate (P) mineral to soil renders apatite addition during each crop growing season which is of great concern from a sustainable agriculture viewpoint. Use of efficient phosphate solubilizing microbes (PSB) is one of the most effective ways to solubilize this apatite mineral in the soil. The current study targeted hydroxyapatite mines to explore, isolate and characterize efficient P solubilizers to solubilize apatite in the soil. Efficiency of isolated microbes to solubilize rock phosphate (hydroxyapatite) and tri-calcium phosphate (TCP) as well as indole-3-acetic acid (IAA) and 1-aminocyclopropane-1-carboxylate deaminase (ACC) activity were tested. Identification and phylogenetic analysis of bacterial and fungal isolates were carried out by 16S rRNA and internal transcribed spacer (ITS) rDNA sequence analyses, respectively. The isolated bacterial strains were identified as Staphylococcus sp. , Bacillus firmus, Bacillus safensis, and Bacillus licheniformis whereas fungal isolates were identified as Penicillium sp. and Penicillium oxalicum. Results showed that the impact of identified strains in combination with three phosphate fertilizers sources (compost, rock phosphate and diammonium phosphate (DAP)) was conspicuous on maize crop grown in pot. Both bacterial and fungal strains increased the P uptake by plants as well as recorded with higher available P in post-harvested soil. Penicillium sp. in combination with compost resulted in maximum P-uptake by plants and post-harvest soil P contents, compared to other combinations of P sources and bio-inoculants. Screening and application of efficient P solubilizers can be a better option to utilize the indigenous phosphate reserves of soil as well as organic amendments for sustainable agriculture.

Some soil microbes, with their diverse inhabitance, biologically active metabolites, and endospore formation, gave them characteristic predominance and recognition among other microbial communities. The present study collected ten soil samples from green land, agricultural and marshy soil sites of Khyber Pakhtunkhwa, Pakistan. After culturing on described media, the bacterial isolates were identified through phenotypic, biochemical and phylogenetic analysis. Our phylogenetic analysis revealed three bacterial isolates, A6S7, A1S6, and A1S10, showing 99% nucleotides sequence similarity with Brevibacillus formosus, Bacillus Subtilis and Paenibacillus dendritiformis. The crude extract was prepared from bacterial isolates to assess the anti-bacterial potential against various targeted multidrug-resistant strains (MDRS), including Acinetobacter baumannii (ATCC 19606), Methicillin-resistant Staphylococcus aureus (MRSA) (BAA-1683), Klebsiella pneumoniae (ATCC 13883), Pseudomonas aeruginosa (BAA-2108), Staphylococcus aureus (ATCC 292013), Escherichia coli (ATCC25922) and Salmonella typhi (ATCC 14028). Our analysis revealed that all bacterial extracts possess activity against Gram-negative and Gram-positive bacteria at a concentration of 5 mg/mL, efficiently restricting the growth of E. coli compared with positive control ciprofloxacin. The study concluded that the identified species have the potential to produce antimicrobial compounds which can be used to control different microbial infections, especially MDRS. Moreover, the analysis of the bacterial extracts through GC-MS indicated the presence of different antimicrobial compounds such as propanoic acid, oxalic acid, phenol and hexadecanoic acid.

Allium cepa L. is a commonly consumed vegetable that belongs to the Amaryllidaceae family and contains nutrients and antioxidants in ample amounts. In spite of the valuable food applications of onion bulb, its peel and outer fleshy layers are generally regarded as waste and exploration of their nutritional and therapeutic potential is still in progress with a very slow progression rate. The present study was designed with the purpose of doing a comparative analysis of the antioxidant potential of two parts of Allium cepa, i.g., bulb (edible part) and outer fleshy layers and dry peels (inedible part). Moreover, the inhibitory effect of the onion bulb and peel extracts on rat intestinal α-glucosidase and pancreatic α-amylase of porcine was also evaluated. The antioxidant potential of onion peel and bulb extracts were evaluated using 2,2-diphenyl- 1-picryl hydrazyl (DPPH), ferric-reducing antioxidant power assay (FRAP), 2,2’-azino-bis- 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assay, H2O2 radical scavenging activity and Fe2+ chelating activity. Total flavonoids and phenolic content of ethanolic extract of onion peel were significantly greater as compared to that of onion bulb. Ethanolic extract of onion peel also presented better antioxidant and free-radical scavenging activity as compared to the ethanolic extract of bulb, while the aqueous extract of bulb presented weakest antioxidative potential. Onion peel extract’s α-glucosidase inhibition potential was also correlated with their phenolic and flavonoid contents. The current findings presented onion peel as a possible source of antioxidative agents and phenolic compounds that might be beneficial against development of various common chronic diseases that might have an association with oxidative stress. Besides, outer dry layers and fleshy peels of onion exhibited higher phenolic content and antioxidant activities, compared to the inner bulb. The information obtained by the present study can be useful in promoting the use of vegetable parts other than the edible mesocarp for several future food applications, rather than these being wasted.

Salmonella enterica serovar Typhi is Gram negative, rod shaped, facultative anaerobic bacterium, belongs to enterobacteriaceae family that causes typhoid fever in humans. This bacterium has become a super bug due to acquisition of multi drug resistance. Bacteria is transmitted through food and water contaminated with human feaces. Present study reports the screening of Adhatoda vasica, Amaranthus hybridus and Aloe barbadensis and their evaluation against multi-drug resistant Salmonella enterica serovar Typhi. Qualitative analysis of ten phytochemicals was conducted using chemical method and Gas Chromatography-Mass Spectrometry (GCMS). Antibacterial activity of plants was carried out by agar well diffusion method on Mueller Hinton agar. Total tannins, total alkaloids and total flavonoids of different parts of three plants were estimated through spectrophotometer. Total tannins content in different parts of plants was present in the given order Amaranthus hybridus leaf > Aloe barbadensis leaf > Adhatoda vasica leaf > Adhatoda vasica flower > Adhatoda vasica stem. Whereas, the order of total flavonoid concentration was Amaranthus hybridus leaf > Aloe barbadensis leaf > Adhatoda vasica leaf > Amaranthus hybridus seed. Total alkaloids have order, Adhatoda vasica leaf > Amaranthus hybridus leaf > Adhatoda vasica flower > Amaranthus hybridus seed > Aloe barbadensis leaf. Results of phytochemical analysis suggested that plants have strong profile of antioxidants, total phenolic contents and various enzymes proposing them best alternate to cure bacterial infections. GC-MS analysis further confirmed stronger phytochemical profile that can be utilized as antagonists to Salmonella enterica serovar Typhi.