Reduction of heavy metal load in food chain: technology assessment

Industrialization and urbanization activities lead to extensive environmental problems and one of the most challenging problems is heavy metal contamination. Heavy metal is responsible for causing adverse effect on human health through food chain contamination. To minimize the effect, different methods are being used for decreasing heavy metal load into the food chain. Most of the traditional methods are either extremely costly or it simply isolate the contaminated site. A promising, relatively new technology for removal of heavy metal from contaminated sites is phytoremediation. There are numerous crops such as sunflower (Helianthus annus), maize (Zea mays), mustard (Brassica compestris), barley (Hordeum vulgare), beet (Beta vulgaris), bitter Gourd (Momordica charantia), brinjal (Solanum melongena), cauliflower (Brassica oleracea var. botrytis), chilli (Capsicum annum), coriander (Coriandrum sativum), fenugreek (Trigonella foenum-graecum), garlic (Alium sativum), ivy gourd (Coccinia indica), lufa (Luffa acutangula), lady’s finger (Abelmoschus esculentus), mint (Mentha piperata), radish (Raphanus sativus), spinach (Spinacia oleracea), tomato (Lycopersicom esculentum), and white gourd (Lagenaria vulgaris) used for remediation of heavy metal. The efficiency of the phytoremediation crops depends upon their biomass production and ability of metal accumulation in their harvestable organs. In addition to this there are some biotechnological approaches for enhancing the property of hyper accumulator plant for metal remediation. Various potential remediation techniques are available that can be used to reduce the heavy metal contamination. Research related to relatively new technology should be promoted and emphasized and expanded in developing countries where heavy metal pollution has already touched alarming level. In the above context present review deals with different approaches to reduce the availability of heavy metal from soil to plants.     

Life table parameters of large white butterfly Pieris brassicae (Lepidoptera: Pieridae) on different cabbage varieties

Effect of four different cole crops (Brassica oleracea var. botrytis, Brassica oleracea var. capitata, Brassica oleracea var. italica and Brassica oleracea var. viridis) on biological parameters of the large white butterfly Pieris brassicae was evaluated at temperature 26 ± 1 °C, 60 ± 5% R. H. and a photoperiod of 16: 8 (L:D) h. The shortest larval and pupal period stages were recorded on B. oleracea var. botrytis (22.18 ± 0.20 days) and (13.32 ± 0.17 days), respectively. The life span was longest on B. oleracea var. viridis (60.43 ± 2.34 days) and shortest on B. oleracea var. botrytis (50.19 ± 0.51 days). The highest percentage of larval and pupal mortality was observed on B. oleracea var. viridis (74%), and (53%), respectively. We found that P. brassicae prefers B. oleracea var. botrytis and B. oleracea var. capitata among cole crops; it is due to the lowest percentage of larval and pupal mortality and the highest rate of life table parameters, including survival rate (lx) and life expectancy (ex), which makes them to be susceptible varieties to this pest. Contrary, a longer developmental time on B. oleracea var. viridis may be attributed to poor nutritional status and reduced survival of the cohort, resulting in high rates of mortality, which was partial resistance to pest. Knowledge of the biology and life table parameters of P. brassicae on different cole crops could be effective in detecting and monitoring the pest infestation, variety selection and crop breeding.     

Deterioration of food in cold stores caused by Rattus rattus and its control—A case study

In a cold store, the house rat, Rattus rattus, damaged fruits and vegetables, including potato (Solanum nigrum), cauliflower (Brassica oleracea), sweet orange (Citrus sinenis), mango (Mangifera indica), grape (Vitis vinifera) and apple (Malus pumilla). Sweet orange and grape were damaged most, and damage to potatoes was relatively low. Packaging materials like jute bags and cardboard boxes were more frequently damaged by rats than were wooden boxes. Rats avoided metallic bait containers because they were made of good conductors of heat. Trapping of rats conducted using insulated traps resulted in the control success of 83–94%.     

Plants as a green alternative for alcohol preparation from aromatic aldehydes

A general methodology for the efficient reduction of aromatic aldehydes and three ketones to their corresponding alcohols (interesting as cosmetic fragrances in their majority) with moderate to excellent chemical yield was achieved by using homogenates of broccoli (B. oleracea var. italic), cauliflower (B. oleracea var. botrytis), beet (B. vulgaris var. cicla), and spinach (S. oleraceae) in aqueous suspension and mild reaction conditions. B. oleracea var. italic and B. oleracea var. botrytis gave the maximum bioconversion yields within short reaction times. Vegetables assayed exhibited an excellent yield (≥ 99%) after 24 hours for aromatic aldehydes.     

A comparative study of DNA synthesis in cotyledon protoplast cultures of Brassica napus,B. campestris and B. oleracea using an immunocytochemical technique

The present study was designed (1) to observe the characterization of 5-bromo-2′-dexoyuridine (BrdU) incorporation into cultured Brassica cotyledon protoplasts and (2) to investigate the genetic differences in the levels of nuclear DNA synthesis (expressed by the percentage of nuclei labelled with BrdU) in cotyledon protoplast cultures from 12 cultivars of three Brassica species (Brassica napus, B. campestris and B. oleracea) at an early stage using immunocytochemistry. Nuclei labelled with BrdU were different from those showing only staining with 4′-6′-diamidino-2-phenylindole (DAPI) under fluorescence and light microscopy. Two to 5% of nuclei were labelled with BrdU after 1 h of culture, indicating that nuclear DNA synthesis occurred at a very early stage of culture. The percentage of nuclei labelled with BrdU increased with time over the length of the culture period. The mean percentage of nuclei labelled with BrdU in the 12 cultivars was about 25% at 24 h after culture initiation. The curve of the increase in percentage of nuclei labelled with BrdU exhibited an S-shape from 1 to 24 h. However, cultivar differences in percentages of nuclei labelled with BrdU were very significant over the time course of 1-24 h from initial culture, with cultivars Eureka (B. napus), Global (B. napus), Narc 82 (B. napus), Bunyip (B. campestris) and Sugar Loaf (B. oleracea) having a consistently higher percentage of nuclei labelled with BrdU than the other cultivars. Species differences were also significant, with cultivars of B. napus showing much higher percentages than the tested cultivars of B. campestris and B. oleracea. The results indicate that the differences in nuclear DNA synthesis in Brassica cotyledon protoplast cultures were most likely at both intra- and interspecies levels.     

Possible phytotoxic metabolites in culture filtrates of Diaporthe phaseolorum var. sojae

Filter-sterile culture filtrates of an isolate of Diaporthe phaseolorum var. sojae (Phomopsis sojae), causal agent of pod and stem blight and seed decay of soybeans (Glycine max), grown on Czapeks-dox broth significantly (P = 0.05) inhibited germination of cabbage (Brassica oleracea), cantaloupe (Cucumis melo), onion (Allium cepa), soybean, and wheat (Triticum vulgare) seeds and wilted soybean seedling cuttings within 24 hr. Inhibition of seed germination and severity of soybean seedling wilt increased with increased concentrations of culture filtrates and increased incubation time of the cultures.     

Analysis of self-incompatibility interactions in 30 resynthesized Brassica napus lines. II. Expression of S-locus glycoproteins (SLGs)

Thirty resynthesized Brassica napus lines with defined S-allele constitution and the ancestral B. oleracea and B. campestris lines were used for the analysis of S- locus glycoproteins (SLGs). The aim of this study was to investigate (1) whether the S-specific glycoproteins of the diploid ancestor lines were also expressed in the amphidiploid hybrids and (2) whether the occurrence of SLG bands was correlated with the activity of the respective S-alleles, which had been tested by means of diallele pollination tests in a previous study. Stigma proteins were separated by isoelectric focusing (IEF)-gel electrophoresis, and glycoprotein bands were identified by Western blotting and Con-A/peroxidase reaction. The SLG bands of the B. campestris parent could be detected in all 30 resynthesized B. napus lines. In contrast, B. oleracea SLG bands could only be detected in 12 resynthesized B. napus lines. Only B. napus lines which carried the dominant B. oleracea S-alleles S₈ and S₂₉ showed respective SLG bands in all cases. Nine B. napus lines showed only glycoprotein bands of the B. campestris parent, although the biological functioning of the B. oleracea S-alleles was demonstrated by test-pollinations. New SLG bands different from those of the B. oleracea and B. campestris parents occurred in 16 B. napus lines. The expression level of the SLGs in B. napus was not correlated with the self-incompatibility phenotype, not only in the case of recessive S-alleles (S₂, S₁₅), but also for dominant alleles (e.g. S₁₄, S₃₂, S₄₅). Received: 22 January 1999 / Accepted: 30 January 1999     

Production and characterization of interspecific hybrids between Brassica maurorum and crop brassicas

 Seven interspecific hybrids were produced between Brassica maurorum (♀), a wild species resistant to Alternaria blight and white rust, and all the monogenomic (B. campestris, B. nigra and B. oleracea) and digenomic (B. juncea, B. napus and B. oleracea) crop brassicas (♂) through embryo rescue. The hybrids were confirmed by means of morphological and cytological studies. All the hybrids were pollen-sterile. Amphidiploids were induced in three of the hybrids: B. maurorum×B. napus, B. maurorum×B. carinata, B. maurorum×B. nigra. The hybrids were also confirmed through DNA analyses for nuclear and organelle genomes using RAPD and RFLP techniques. Received: 31 July 1998 / Accepted: 14 August 1998     

Consumption of redox energy by glutathione metabolism contributes to hypoxia/ reoxygenation-induced injury in astrocytes

The assumption of oxidative stress as a mechanism in oxalate induced renal damage suggests that antioxidants might play a beneficial role against oxalate toxicity. An in vivo model was used to investigate the effect of C-phycocyanin (from aquatic micro algae; Spirulina spp.), a known antioxidant, against calcium oxalate urolithiasis. Hyperoxaluria was induced in two of the 4 groups of Wistar albino rats (n = 6 in each) by intraperitoneally injecting sodium oxalate (70,mg/kg body weight). A pretreatment of phycocyanin (100,mg/kg body weight) as a single oral dosage was given, one hour prior to oxalate challenge. An untreated control and drug control (phycocyanin alone) were employed. Phycocyanin administration resulted in a significant improvement (p < 0.001) in the thiol content of renal tissue and RBC lysate via increasing glutathione and reducing malondialdehyde levels in the plasma of oxalate induced rats (p < 0.001), indicating phycocyanin’s antioxidant effect on oxalate mediated oxidative stress. Administering phycocyanin after oxalate treatment significantly increased catalase and glucose-6-phosphate dehydrogenase activity (p < 0.001) in RBC lysate suggesting phycocyanin as a free radical quencher. Assessing calcium oxalate crystal retention in renal tissue using polarization microscopy and renal ultrastructure by electron microscopy reveals normal features in phycocyanin – pretreated groups. Thus the study presents positive pharmacological implications of phycocyanin against oxalate mediated nephronal impairment and warrants further work to tap this potential aquatic resource for its medicinal application. (Mol Cell Biochem xxx: 1–7, 2004)     

Brassica taxonomy based on nuclear restriction fragment length polymorphisms (RFLPs)

Summary RFLPs were used to study genome evolution and phylogeny in Brassica and related genera. Thirtyeight accessions, including 10 accessions of B. rapa (syn. campestris), 9 cultivated types of B. oleracea, 13 nine-chromosome wild brassicas related to B. oleracea, and 6 other species in Brassica and allied genera, were examined with more then 30 random genomic DNA probes, which identified RFLPs mapping to nine different linkage groups of the B. rapa genome. Based on the RFLP data, phylogenetic trees were constructed using the PAUP microcomputer program. Within B. rapa, accessions of pak choi, narinosa, and Chinese cabbage from East Asia constituted a group distinct from turnip and wild European populations, consistent with the hypothesis that B. rapa had two centers of domestication. A wild B. rapa accession from India was positioned in the tree between European types and East Asian types, suggesting an evolutionary pathway from Europe to India, then to South China. Cultivated B. oleracea morphotypes showed monophyletic origin with wild B. oleracea or B. alboglabra as possible ancestors. Various kales constitute a highly diverse group, and represent the primitive morphotypes of cultivated B. oleracea from which cabbage, broccoli, cauliflower, etc. probably have evolved. Cauliflower was found to be closely related to broccoli, whereas cabbage was closely related to leafy kales. A great diversity existed among the 13 collections of nine-chromosome wild brassicas related to B. oleracea, representing various taxonomic states from subspecies to species. Results from these studies suggested that two basic evolutionary pathways exist for the diploid species examined. One pathway gave rise to B. fruticulosa, B. nigra, and Sinapis arvensis, with B. adpressa or a close relative as the initial ancestor. Another pathway gave rise to B. oleracea and B. rapa, with Diplotaxis erucoides or a close relative as the initial ancestor. Raphanus sativus and Eruca sativus represented intermediate types between the two lineages, and might have been derived from introgression or hybridization between species belonging to different lineages. Molecular evidence for an ascending order of chromosome numbers in the evolution of Brassica and allied genera was obtained on the basis of RFLP data and phylogenetic analysis.     

BrpSPL9 (Brassica rapa ssp. pekinensis SPL9) controls the earliness of heading time in Chinese cabbage

The leafy heads of cabbage (Brassica oleracea), Chinese cabbage (Brassica rapa ssp. pekinensis), Brussels sprouts (B. oleracea ssp. gemmifera) and lettuce (Lactuca sativa) comprise extremely incurved leaves that are edible vegetable products. The heading time is important for high quality and yield of these crops. Here, we report that BrpSPL9‐2 (B. rapa ssp. pekinensis SQUAMOSA PROMOTER BINDING‐LIKE 9‐2), a target gene of microRNA brp‐miR156, controls the heading time of Chinese cabbage. Quantitative measurements of leaf shapes, sizes, colour and curvature indicated that heading is a late adult phase of vegetative growth. During the vegetative period, miR156 levels gradually decreased from the seedling stage to the heading one, whereas BrpSPL9‐2 and BrpSPL15‐1 mRNAs increased progressively and reached the highest levels at the heading stage. Overexpression of a mutated miR156‐resistant form of BrpSPL9‐2 caused the significant earliness of heading, concurrent with shortening of the seedling and rosette stages. By contrast, overexpression of miR156 delayed the folding time, concomitant with prolongation of the seedling and rosette stages. Morphological analysis reveals that the significant earliness of heading in the transgenic plants overexpressing BrpSPL9‐2 gene was produced because the juvenile phase was absent and the early adult phase shortened, whereas the significant delay of folding in the transgenic plants overexpressing Brp‐MIR156a was due to prolongation of the juvenile and early adult phases. Thus, miR156 and BrpSPL9 genes are potentially important for genetic improvement of earliness of Chinese cabbage and other crops.     

A review of sources of resistance to turnip yellows virus (TuYV) in Brassica species

Turnip yellows virus (TuYV; previously known as beet western yellows virus) causes major diseases of Brassica species worldwide resulting in severe yield-losses in arable and vegetable crops. It has also been shown to reduce the quality of vegetables, particularly cabbage where it causes tip burn. Incidences of 100% have been recorded in commercial crops of winter oilseed rape (Brassica napus) and vegetable crops (particularly Brassica oleracea) in Europe. This review summarises the known sources of resistance to TuYV in B. napus (AACC genome), Brassica rapa (AA genome) and B. oleracea (CC genome). It also proposes names for the quantitative trait loci (QTLs) responsible for the resistances, Tu rnip Y ellows virus R esistance (TuYR), that have been mapped to at least the chromosome level in the different Brassica species. There is currently only one known source of resistance deployed commercially (TuYR1). This resistance is said to have originated in B. rapa and was introgressed into the A genome of oilseed rape via hybridisation with B. oleracea to produce allotetraploid (AACC) plants that were then backcrossed into oilseed rape. It has been utilised in the majority of known TuYV-resistant oilseed rape varieties. This has placed significant selection pressure for resistance-breaking mutations arising in TuYV. Further QTLs for resistance to TuYV (TuYR2-TuYR9) have been mapped in the genomes of B. napus, B. rapa and B. oleracea and are described here. QTLs from the latter two species have been introgressed into allotetraploid plants, providing for the first time, combined resistance from both the A and the C genomes for deployment in oilseed rape. Introgression of these new resistances into commercial oilseed rape and vegetable brassicas can be accelerated using the molecular markers that have been developed. The deployment of these resistances should lessen selection pressure for resistance-breaking isolates of TuYV and thereby prolong the effectiveness of each other and extant resistance.     

Variation in abundance of predicted resistance genes in the Brassica oleracea pangenome

Brassica oleracea is an important agricultural species encompassing many vegetable crops including cabbage, cauliflower, broccoli and kale; however, it can be susceptible to a variety of fungal diseases such as clubroot, blackleg, leaf spot and downy mildew. Resistance to these diseases is meditated by specific disease resistance genes analogs (RGAs) which are differently distributed across B. oleracea lines. The sequenced reference cultivar does not contain all B. oleracea genes due to gene presence/absence variation between individuals, which makes it necessary to search for RGA candidates in the B. oleracea pangenome. Here we present a comparative analysis of RGA candidates in the pangenome of B. oleracea. We show that the presence of RGA candidates differs between lines and suggests that in B. oleracea, SNPs and presence/absence variation drive RGA diversity using separate mechanisms. We identified 59 RGA candidates linked to Sclerotinia, clubroot, and Fusarium wilt resistance QTL, and these findings have implications for crop breeding in B. oleracea, which may also be applicable in other crops species.     

Expression profiles and genomic organisation of group A protein phosphatase 2C genes in Brassica oleracea

We investigated the expression profiles and genomic organisation of the ABA‐responsive genes encoding protein phosphatases 2C (PP2C, group A members) in Brassica oleracea to better understand their functional and genetic relations. Gene expression profiling of drought responsive genes in B. oleracea and Arabidopsis thaliana revealed significant differences in the gene expression pattern of a key regulator of ABA signalling—ABI1 PP2C. This finding prompted us to study genetic relations within the PP2Cs group A in the Brassica species. Twenty homologous B. oleracea sequences were identified and characterised as putative PP2C group A members. Phylogenetic analysis revealed that the B. oleracea homologues were closely related to the particular members of the A. thaliana PP2C. The genetic analysis corroborated the presence of two to three gene copies in B. oleracea in comparison to the nine unique PP2C genes in the A. thaliana genome. Gene expression analyses showed significant differences in PP2C gene expression pattern in B. oleracea. Our results indicate that PP2C‐based drought stress signalling in B. oleracea has evolved distinctly. Different reactions of particular B. oleracea PP2C genes to drought stress and ABA treatment indicate low conservation of gene expression patterns and functional divergence between B. oleracea and A. thaliana homologous genes.     

The titres of lectins in the haemolymph of Lacanobia oleracea and the effects of parasitism by the ectoparasitoid wasp Eulophus pennicornis

Serum from larvae of Lacanobia oleracea L. (Lepidoptera; Noctuidae) parasitized by Eulophus pennicornis (Hymenoptera; Eulophidae) and from normal non‐parasitized larvae is capable of agglutinating rabbit, sheep, calf, goat, chicken, horse and human erythrocytes, but not yeast. Studies with a range of inhibitory carbohydrates showed that serum lectins(s) had specificity for sugars containing galactose and for rhamnose, and for the glycosubstances fetuin and asialofetuin. Lectin activity is heat‐labile and is not dependent on calcium. Parasitism by E. pennicornis caused an increase in the agglutination titre of the serum from larvae of L. oleracea but not an increase in specific activity (titre per mg protein per ml). However, when venom from the venom gland of female wasps was injected into L. oleracea larvae, both the agglutinating activity and the specific activity of the larval serum increased. The possible causes of this increase are discussed. It is suggested that venom contains antigenic components which, when injected into the haemocoel of the L. oleracea larva, may be increasing lectin synthesis and/or release into the serum.     

Alignment of the conserved C genomes of Brassica oleracea and Brassica napus

A population of 169 microspore-derived doubled-haploid lines was produced from a highly polymorphic Brassica oleracea cross. A dense genetic linkage map of B. oleracea was then developed based on the segregation of 303 RFLP-defined loci. It is hoped that these lines will be used by other geneticists to facilitate the construction of a unified genetic map of B. oleracea. When the B. oleracea map was compared to one ofB. napus (Parkin et al. 1995), based on the same RFLP probes (Sharpe et al. 1995), good collinearity between the C-genome linkage groups of the two species was observed.     

Differentiation between larvae of Tipula paludosa and Tipula oleracea (Diptera: Tipulidae) using isoelectric focusing, and their occurrence in grassland in northern Britain

Thin layer agarose isoelectric focusing (IEF) was used to separate proteins from the larvae of Tipula oleracea Linnaeus and Tipula paludosa Meigen (Diptera, Nematocera). Silver staining revealed protein banding patterns which consistently distinguished these two species at any stage in their life cycles. Within the pH range 5–6 Tipula paludosa contained one major protein band and T. oleracea two bands, with the pI value of the T. paludosa protein being slightly higher than those of T. oleracea. The IEF method is particularly useful for the larval stages of these species because they are often visually inseparable. Leather jackets obtained during a survey of Northern Ireland and north-eastern and western Scotland were tested to determine the distribution and frequency of these species occurring in grassland. In each area surveyed T. paludosa predominated with only one field in Northern Ireland and north-eastern Scotland found to contain T. oleracea. In western Scotland T. oleracea occurred in five fields each year of the survey, and was locally abundant on the Isle of Bute in the 1990/91 survey making up 15% of the total larvae tested.     

Chlorophyll breakdown in spinach: on the structure of five nonfluorescent chlorophyll catabolites*

In extracts of senescent leaves of spinach (Spinacia oleracea), five colourless compounds with UV/Vis-characteristics of nonfluorescent chlorophyll catabolites (NCCs) were detected and tentatively named So-NCCs. The most abundant polar NCC in the leaves of this vegetable, So-NCC-2, had been isolated earlier and its constitution was determined by spectroscopic means. The catabolite So-NCC-2 was found to be an epimer of a polar NCC from barley (Hordeum vulgare), the first non-green chlorophyll catabolite from a higher plant to be structurally analyzed. Here, we report on the isolation of four additional So-NCCs from the extracts of senescent leaves of Sp. oleracea by two- (or multi-)stage chromatographic purification and on their structural characterization. The constitution of So-NCC-3 could be determined by spectroscopic analysis in combination with chemical correlation with a known NCC from Cercidiphyllum japonicum (Cj-NCC): So-NCC-3 was identified as the hydrolysis product of the methyl ester function of Cj-NCC. The less polar catabolite So-NCC-4 could be directly identified with Cj-NCC. Two further So-NCCs, So-NCC-1 and So-NCC-5, were detected only in trace amounts. Five structurally related nonfluorescent chlorophyll catabolites (So-NCCs) are thus present in senescent leaves of spinach. The structures of this set of So-NCCs indicate several peripheral refunctionalization reactions and inform on the late catabolic transformations during leaf senescence. The transformation of the tetrapyrrolic skeleton in chlorophyll catabolism in spinach and in C. japonicum is revealed to exhibit a common stereochemical pattern. This revised version was published online in June 2006 with corrections to the Cover Date.     

Forward and reverse genetics of rapid-cycling Brassica oleracea

Seeds of rapid-cycling Brassica oleracea were mutagenized with the chemical mutagen, ethylmethane sulfonate. The reverse genetics technique, TILLING, was used on a sample population of 1,000 plants, to determine the mutation profile. The spectrum and frequency of mutations induced by ethylmethane sulfonate was similar to that seen in other diploid species such as Arabidopsis thaliana. These data indicate that the mutagenesis was effective and demonstrate that TILLING represents an efficient reverse genetic technique in B. oleracea that will become more valuable as increasing genomic sequence data become available for this species. The extensive duplication in the B. oleracea genome is believed to result in the genetic redundancy that has been important for the evolution of morphological diversity seen in today’s B. oleracea crops (broccoli, Brussels sprouts, cauliflower, cabbage, kale and kohlrabi). However, our forward genetic screens identified 120 mutants in which some aspect of development was affected. Some of these lines have been characterized genetically and in the majority of these, the mutant trait segregates as a recessive allele affecting a single locus. One dominant mutation (curly leaves) and one semi-dominant mutation (dwarf-like) were also identified. Allelism tests of two groups of mutants (glossy and dwarf) revealed that for some loci, multiple independent alleles have been identified. These data indicate that, despite genetic redundancy, mutation of many individual loci in B. oleracea results in distinct phenotypes. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Biotransformation of struvite by Aspergillus niger: phosphate release and magnesium biomineralization as glushinskite

Struvite (magnesium ammonium phosphate-MgNH₄PO₄·6H₂O), which can extensively crystallize in wastewater treatments, is a potential source of N and P as fertilizer, as well as a means of P conservation. However, little is known of microbial interactions with struvite which would result in element release. In this work, the geoactive fungus Aspergillus niger was investigated for struvite transformation on solid and in liquid media. Aspergillus niger was capable of solubilizing natural (fragments and powder) and synthetic struvite when incorporated into solid medium, with accompanying acidification of the media, and extensive precipitation of magnesium oxalate dihydrate (glushinskite, Mg(C₂O₄).2H₂O) occurring under growing colonies. In liquid media, A. niger was able to solubilize natural and synthetic struvite releasing mobile phosphate (PO₄³⁻) and magnesium (Mg²⁺), the latter reacting with excreted oxalate resulting in precipitation of magnesium oxalate dihydrate which also accumulated within the mycelial pellets. Struvite was also found to influence the morphology of A. niger mycelial pellets. These findings contribute further understanding of struvite solubilization, element release and secondary oxalate formation, relevant to the biogeochemical cycling of phosphate minerals, and further directions utilizing these mechanisms in environmental biotechnologies such as element biorecovery and biofertilizer applications.