Biotransformation of congo red in a UASB reactor under salinity conditions using immobilized redox mediator in granular activated carbon

Azo dyes are susceptible to be treated by reductive biotransformation process under anaerobic conditions. The process can be accelerated by the addition of quinones and humic substances acting as redox mediators (RM). In this study, the anthraquinone-2-sulfonate (AQS) was immobilized on granular activated carbon (GAC) to evaluate the reductive biotransformation of congo red (CR) in an up-flow anaerobic sludge blanket reactor (UASB). The syudy was divided in five stages, where the reactors with immobilized RM and without RM were operated under different salinity levels (1% and 3%) and hydraulic retention times (HRT = 5 and 10 h). The reactor with immobilized RM (GAC-AQS) achieved a decolorization efficiency of 96.1% and substrate consumption of 98.8% with a HRT = 15 h and 1% of salinity. Nonetheless, with a salinity of 3% and the same HRT, the efficiency was similar (95.6%). The reactor provided with unmodified GAC achieved values below those observed in the reactor GAC-AQS, with decolorization efficiencies of 90.8% and 75.8%, and substrate consumption of 97.1% and 88.4%, for the stages IV and V, respectively. The microbial consortium sued was able to promote the biotransformation of azo dye and no inhibitory effects were identified.

Azospirillum brasilense stimulate the growth in Arabidopsis thaliana through the target of rapamycin protein

Azospirillum spp., one of the best studied genus of plant growth promoting rhizobacteria. These rhizobacteria are able to colonize hundreds of plant species and improve their growth, development and productivity. The target of rapamycin (TOR) protein is a central component of the TOR signaling pathway, which regulates cell growth and metabolism in response to environment cues in eukaryotes. In this study, the TOR function was analyzed in Arabidopsis thaliana L. plants inoculated with the rhizobacteria Azospirillum brasilense. Arabidopsis seedlings tor-es, which express an interference RNA in presence of estradiol and decrease TOR expression, showed an inhibition in the growth and lateral root formation, with or without 1x102 CFU/mL of the inoculum. In addition, a morphological analysis of the root showed an inhibition in the root hair formation. The results suggest that A. brasilense controls A. thaliana growth through TOR signaling pathway.

In vitro biological activity of ethanolic extracts from plants of the Meliaceae family on Diaphorina citri Kuwayama 1908 (Hemiptera: Liviidae)

In vitro effect of ethanolic extracts of Azadirachta indica seeds, Melia azedarach and Swietenia humilis (Meliaceae) were evaluated on the mortality, repellency and oviposition of Diaphorina citri (Hemiptera: Liviidae). Toxicity was determined by the placement of adults and nymphs on orange leaf discs (Citrus sinensis cv. Valencia) previously sprayed or immersed in the treatments. The repellency was estimated through an exposition of adults to the treated leaf, in an experimental arena for 24 h. In order to inhibit oviposition, Murraya paniculata sprouts sprinkled with 2.5 mL of solution were used. The ethanolic extracts from the three meliaceus showed toxicity on nymphs and adults; however, adults evidenced the toxic effect as of 100.0 mg/mL, while nymphs did at 4.10 mg/mL. With a repellent effect, the 100 mg/mL solution stands out, with 82 and 78% for A. indica and S. humilis, respectively; effect associated to the concentration and the time. The oviposition was affected by ethanolic extracts of S. humilis and A. indica at 100.0 mg/mL. It is inferred that the ethanol extracts from S. humilis and A. indica present potential to be considered in the development of alternatives for the integrated management of D. citri.

Metabolic capacity of probiotic mixed cultures formed by Lactobacillus and Bifidobacterium strains for use in functional fermented dairy foods

The metabolic capacity of probiotic mixed cultures formed by Lactobacillus and Bifidobacterium strains was assessed through the determination of the acidification profile and the production of amino acids and volatile compounds, during the fermentation of ultra-pasteurized skim milk. Two mixed cultures formed by [L. acidophilus + B. bifidum] and [L. acidophilus + B. animalis] stood out in the production of essential amino acids: His, Ile, Leu, Met, Thr, Trp and Val. As well as increased production of volatile compounds such as: acetoin, 2-heptanone, 2-nonanone, acetic acid, acid butanoic and hexanoic acid, in contrast to commercial fermented dairy products. Additionally, these bacterial mixed cultures were characterized by the production of distinctive volatile compounds: 1-heptanol, diisobutylcarninol, hemellitol, 1-dodecanol, acetone, 2-pentanone, 2-undecanone, ethyl acetate, benzaldehyde as well as valeric, acetyl valeric and isopropylpyruvic acids. Finally, the culture formed by [L. acidophilus + B. bifidum] presented a good acidification profile with a lactic acid production of 26.1 ± 0.1 g / L and pH 3.6 at the end of fermentation. This data suggests a great potential of these mixed cultures to improve the nutritional value and organoleptic characteristics of fermented dairy products, when added as starter or adjunct cultures in the fermentation process.

Antioxidant gene expression, chlorophyll, and starch content in Persian lime (Citrus latifolia Tanaka Ex Q. Jiménez) trees with HLB by application of elicitors of plant resistance

Persian lime is economically important for Mexico. However, the disease known as Huanglongbing (HLB) causes chlorosis symptoms in the foliage that affect the growth and decreases the yield of the trees. The expression of chlorosis symptoms is associated with starch accumulation and inhibition of antioxidant activity. The objective of the present work was to determine the effect of the application of three resistance elicitors on the expression of three antioxidant genes and on starch and chlorophyll content in Persian lime trees with HLB. Salicylic acid (SA), jasmonic acid (JA) or gamma-aminobutyric acid (GABA) were applied every eight days for nine weeks using a completely randomized design and a one-way ANOVA was performed for the analysis. Expression of APX, CAT and SOD genes was quantified at week nine at four different times. Starch and total chlorophyll content was estimated every three weeks by spectrophotometric methods. The application of the elicitors significantly increased the expression of the three genes, with SA and GABA generating the greatest increase at different times of application. No difference was found in starch and total chlorophyll content at most of the times evaluated. The use of resistance elicitors is promising in the management of HLB in plots already infected, seeking to extend the productive life of the orchards and thus counteract the economic losses caused by HLB.

Genetic characterization of the microbiota of artisan fresh cheese from the Papaloapan region

The population of the Papaloapan region consume artisan fresh cheeses and no pathogen outbreaks have been reported recently. The microbiota is responsible to develop desirable characteristics of cheeses and undesirable characteristics due to the presence of certain pathogens microorganisms. Therefore, to identify the microorganisms of fresh cheeses is an important issue for the producers, consumers, and authorities. 11 Artisan fresh cheese samples from the Papaloapan region were collected in the summer and 11 samples in winter to characterize their microbiota. Traditional microbial techniques were used to identify the fungus and the amplification of the 16S rRNA gene and PCR-denaturing gradient gel electrophoresis (DGGE) The population of the Papaloapan region consume artisan fresh cheeses and no pathogen outbreaks have been reported recently. The microbiota is responsible to develop desirable characteristics of cheeses and undesirable characteristics due to the presence of certain pathogens microorganisms. Therefore, to identify the microorganisms of fresh cheeses is an important issue for the producers, consumers, and authorities. 11 Artisan fresh cheese samples from the Papaloapan region were collected in the summer and 11 samples in winter to characterize their microbiota. Traditional microbial techniques were used to identify the fungus and the amplification of the 16S rRNA gene and PCR-denaturing gradient gel electrophoresis (DGGE) The population of the Papaloapan region consume artisan fresh cheeses and no pathogen outbreaks have been reported recently. The microbiota is responsible to develop desirable characteristics of cheeses and undesirable characteristics due to the presence of certain pathogens microorganisms. Therefore, to identify the microorganisms of fresh cheeses is an important issue for the producers, consumers, and authorities. 11 Artisan fresh cheese samples from the Papaloapan region were collected in the summer and 11 samples in winter to characterize their microbiota. Traditional microbial techniques were used to identify the fungus and the amplification of the 16S rRNA gene and PCR-denaturing gradient gel electrophoresis (DGGE) method was used for bacteria identification. For all the samples, the presence of aerobic mesophiles, Streptococcus mesophiles and thermophiles, Lactobacillus mesophiles, Leuconostoc, total coliforms, Staphylococcus aureus, molds, and yeasts were identified. The complexity and variety of microorganisms in the summer and winter seasons samples were not significantly different. In conclusion, all samples of fresh artisan cheeses were under high microbial loads. Lactic Acid Bacteria (LAB) were in a typical load, as established by the quality and safety standards in the food industry. Conversely, pathogenic bacteria exceeded this limit. The microorganisms present in the fresh artisanal cheeses of the Papaloapan region were identified with precision, regarding the count and their diversity. A recommendation for the cheese manufacturers is to prepare starter cultures by selecting the appropriate microorganisms to produce the desirable characteristics such as aroma and flavor and reduce the risk of microbial infections by using pasteurized milk.

Saving the Planet with Appropriate Biotechnology: 5. An Action Plan

We evaluate suggestions to harness the ability of calcifying organisms (molluscs, crustacea, corals and coccolithophore algae) to remove permanently CO2 from the atmosphere into solid (crystalline) CaCO3 for atmosphere remediation. Here, we compare this blue carbon with artificial/industrial Carbon dioxide Capture & Storage (CCS) solutions. An industrial CCS facility delivers, at some cost, captured CO2, nothing more. But aquaculture enterprises cultivating shell to capture and store atmospheric CO2 also produce nutritious food and perform many ecosystem services like water filtration, biodeposition, denitrification, reef building, enhanced biodiversity, shoreline stabilisation and wave management. We estimate that a mussel farm sequesters three times as much carbon as terrestrial ecosystems retain. Blue carbon farming does not need irrigation or fertiliser, nor conflict with the use of scarce agricultural land. Blue carbon farming can be combined with restoration and conservation of overfished fisheries and usually involves so little intervention that there is no inevitable conflict with other activities. We calculate that this paradigm shift (from ‘shellfish as food’ to ‘shellfish for carbon sequestration’) makes bivalve mollusc farming and microalgal farming enterprises, viable, profitable, and sustainable, alternatives to all CCUS industrial technologies and terrestrial biotechnologies in use today.

Bioactive compounds from fungi with antiviral activities: Mechanism of action and biosynthetic pathways

Viral infections have affected human health, causing critical pandemics and mortality worldwide. Viruses can also cause enormous economic problems for society globally. Bioactive compounds isolated from fungi (both edible and nonedible) have shown potential activity against viruses. In this review, we describe the fungal natural compounds that have exhibited capability to inhibit some human pathogenic viruses, such as human immunodeficiency virus, dengue virus, herpes simplex virus, bovine herpes virus, influenza virus, respiratory syndrome virus, hepatitis virus among others. We focused on the biosynthetic pathways of fungal bioactive compounds and addressed the current knowledge about their antiviral mechanisms of action and specific targets. Fungal bioactive compounds are able to inhibit viral reproduction, blocking viral penetration, replication or translation as well as integrase or protease action. Fungal compounds able to inhibit protease such as. ganodermatriol, ergosterol, terpenoids, ganoderic acid GS-2, ganoderiol, sterigmatocystin, emericellin, cordycepin, ergosterol peroxide, myristic acid among others, may have a significant value to society at present, as they may have the potential to treat severe viral respiratory infections. Fungi represent a potential natural source of bioactive molecules that can be exploited for treating viral infections, which represent one of the main causes of disease worldwide. However, extensive investigations on clinical trials are required for the introduction of new antiviral agents into the market.

Release of reducing sugars from water hyacinth by thermochemical and enzymatic hydrolysis

Water hyacinth (Eichhornia crassipes) is considered a pernicious herb in many parts of the world due to its rapid growth. However, for its high content of cellulose and hemicellulose, it could be considered as raw material to produce fermentable sugars. In this work, the effect of sulfuric acid concentration by thermochemical pretreatment and enzymatic hydrolysis on the release of sugars from water hyacinth was evaluated. Initially, the effect of the sulfuric acid concentration from 1.5 to 9% at 120 ºC was evaluated. With 1.5%, the release of reducing sugars was 160 milligrams of reducing sugars per gram of dry matter (mg red-sug/g dm). After the thermochemical pretreatment, the enzymatic hydrolysis with the cellulase complex (NS22086) allowed obtaining a reducing sugars concentration up to 317 mg red-sug/g dm. These thermochemical and enzymatic approaches to recover reducing sugars from water hyacinth is promising and should be evaluated for bioprocess using reducing sugars as the main source of carbon, such as bioethanol production.

Saving the planet with appropriate biotechnology: 1. Diagnosing the problems

We give a plain language guide to the Earth’s carbon cycle by briefly summarising the observations and origins of increased levels of greenhouse gases, mainly CO2 but including CH4 and N2O, in our atmosphere. The only tenable explanation for our atmosphere’s present state is that it is the consequence of mankind’s excessive use of fossil fuels since the Industrial Revolution onwards. We deal with the arguments that deny the truth of this, then illustrate the Earth’s global carbon cycle, which was almost exactly in equilibrium for several thousand years while humans were evolving, before industrial humans intervened. We describe how the excess greenhouse gas emissions are projected to change the global climate over this century and beyond and discuss ‘dangerous anthropogenic interference’ (DAI), ‘reasons for concern’ (RFCs) and climate tipping points. Finally, we give a short account of the various improved management, engineering and natural climate solutions advocated to increase carbon storage and/or avoid greenhouse gas emissions across global forests, wetlands, grasslands, agricultural lands, and industry. This review concludes with our basic message, which is that cultivation of aquatic calcifiers (coccolithophore algae, corals, crustacea and molluscs) offers the only effective and permanent carbon sequestration strategy.