The attachment of microbes on biotic or abiotic surfaces to form biofilm structures has a great impact on biodegradation and biosynthesis in nature. Various interactions in such biofilms and their extracellular polymeric substances (EPS) layer make them considerably different in physiology and action, compared to that of their individual microbes in planktonic (free swimming) mode of growth. Expression of new genes is up-regulated in the biofilm cells, due in part to the cellular interactions, compared with the planktonic cells. Formation of fungal-bacterial biofilms (FBB) by bacterial colonization on biotic fungal surface gives the biofilm enhanced metabolic activities compared to monocultures, and perhaps multi-species bacterial or fungal biofilms on abiotic surfaces. Incorporation of a N 2 -fixing rhizobial strain to the FBB to form fungal-rhizobial biofilms (FRB) has been shown to improve potential biofilm applications in N-deficient settings and in the production of biofilmed inocula for biofertilizers and biocontrol in plants. Their applications in agricultural and environmental settings, enzyme technology, drug discovery studies and energy research are being investigated. Thus, it has already been shown that the use of the FBB is a promising technology for many applications. This review deals with the different areas in which FBB/FRB have been seen to be applied with successful results as well as the numerous emerging avenues in which they show promising potential.

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Aquatic ecosystems are contaminated with heavy metals by natural and anthropogenic sources. Whilst some heavy metals are necessary for plants as micronutrients, others can be toxic to plants and humans even in trace concentrations. Among heavy metals, cadmium (Cd), arsenic (As), chromium (Cr), lead (Pb), and mercury (Hg) cause significant damage to aquatic ecosystems and can invariably affect human health. Rice, a staple diet of many nations, and other aquatic plants used as vegetables in many countries, can bioaccumulate heavy metals when they grow in contaminated aquatic environments. These metals can enter the human body through food chains, and the presence of heavy metals in food can lead to numerous human health consequences. Heavy metals in aquatic plants can affect plant physicochemical functions, growth, and crop yield. Various mitigation strategies are being continuously explored to avoid heavy metals entering aquatic ecosystems. Understanding the levels of heavy metals in rice and aquatic plants grown for food in contaminated aquatic environments is important. Further, it is imperative to adopt sustainable management approaches and mitigation mechanisms. Although narrowly focused reviews exist, this article provides novel information for improving our understanding about heavy metal accumulation in rice and aquatic plants, addressing the gaps in literature.

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Molecular spectroscopic detection techniques, such as Fourier transform infrared spectroscopy (FTIR), provides additional specificity for isomers where often mass spectrometry (MS) fails, due to similar fragmentation patterns. A hyphenated system of gas chromatography (GC) with FTIR via a light-pipe interface is reported in this study to explore a number of GC–FTIR analytical capabilities. Various compound classes were analyzed—aromatics, essential oils and oximes. Variation in chromatographic peak parameters due to the light-pipe was observed via sequentially-located flame ionization detection data. Unique FTIR spectra were observed for separated mixtures of essential oil isomers having similar mass spectra. Presentation of GC×FTIR allows a ‘comprehensive’-style experiment to be developed. This was used to obtain spectroscopic/separation profiles for interconverting oxime species with their individual spectra in the overlap region being displayed on a color contour plot. Partial least square regression provides multivariate quantitative analysis of co-eluting cresol isomers derived from GC–FTIR data. The model resulted in an R2 of 0.99. Prediction was obtained with R2 prediction value of 0.88 and RMSEP of 0.57, confirming the method’s suitability. This study explores the potential of GC–FTIR hyphenation and re-iterates its value to derive unambiguous and detailed molecular information which is complementary to MS.