Bacterial Mixture Research Articles

The bacterial mixture effect of Azotobacter and Azospirrilum on nitrogen content and harvest date of upland red rice cultivar

The research aims were to analyse the effect of bacterial mixture of Azotobacter and Azospirrilum on the nitrogen content and harvest date of upland red rice. This research was conducted in Agriculture Farm of Agriculture Faculty in Halu Oleo University. The research was arranged in a split plot design. The bacterial mixture dosage as main plot and different of cultivar as sub plot. The bacterial mixture dosage were without application bacterial mixture, Bacterial combination mixture of Azotobacter 2.5 L ha−1 + Azospirillum 2.5 L ha−1, and Bacterial combination mixture of Azotobacter 5.0 L ha−1 + Azospirillum 5.0 L ha−1. The cultivar tested were Labandiri, Jangkobembe, Ranggohitam, and Paedara. This research shows that application of bacterial mixture had no significant effect on nitrogen leaf content, but had a significant effect on flowering time and harvesting. It was found that flowering time tended to accelerate, but on harvesting-date parameters tended to be prolonged.

Effect of Some Microorganisms on Controlling Fusarium Wilt of Roselle (Hibiscus sabdariffa L.)

Roselle (Hibiscus sabdariffa L.) is one of the most crucial medicinal plants all over the world. The present study was carried out with the intention of solving some problems related to soil-borne diseases. Fusarium oxysporum is associated with wilt disease of roselle plant. The application of some microbiota i.e., a mixture of Pseudomonas fluorescens (PSR-11), Bacillus subtilis (BSR-8), Pleurotus ostreatus and mycorrhizeen® individually or in combination were investigated for controlling wilt disease, growth, and yield of roselle plant. The study was conducted in sandy textured soil under sprinkler irrigation of Ismailia Agricultural Research Station, Ismailia, Egypt. Under greenhouse conditions, all the tested bioagents reduced wilt incidence and increased the percentage of survived plants. The conglomeration of the bacterial mixture of Pseudomonas fluorescens and Bacillus subtilis, Pleurotus ostreatus and mycorrhizeen® was more effective in controlling wilt disease than using any of them individually. The application of the investigated bioagents showed a significant increase in phenol, photosynthetic pigments, and dehydrogenase contents, as well as root colonization percent. The obtained results showed the ability of B. subtilis and P. fluorescens to produce lytic enzymes such as β-1-3 glucanase, β-1-4 glucanase, chitinase and protease, in addition to their production of siderophore and HCN. The consortium of all microbiota gave the best results for growth and yield parameters of roselle plant.

Honeybees Exposure to Natural Feed Additives: How Is the Gut Microbiota Affected?

The role of a balanced gut microbiota to maintain health and prevent diseases is largely established in humans and livestock. Conversely, in honeybees, studies on gut microbiota perturbations by external factors have started only recently. Natural methods alternative to chemical products to preserve honeybee health have been proposed, but their effect on the gut microbiota has not been examined in detail. This study aims to investigate the effect of the administration of a bacterial mixture of bifidobacteria and Lactobacillaceae and a commercial product HiveAliveTM on honeybee gut microbiota. The study was developed in 18 hives of about 2500 bees, with six replicates for each experimental condition for a total of three experimental groups. The absolute abundance of main microbial taxa was studied using qPCR and NGS. The results showed that the majority of the administered strains were detected in the gut. On the whole, great perturbations upon the administration of the bacterial mixture and the plant-based commercial product were not observed in the gut microbiota. Significant variations with respect to the untreated control were only observed for Snodgrassella sp. for the bacterial mixture, Bartonella sp. in HiveAliveTM and Bombilactobacillus sp. for both. Therefore, the studied approaches are respectful of the honeybee microbiota composition, conceivably without compromising the bee nutritional, social and ecological functions.

Smells Like Teen Spirit-A Model to Generate Laundry-Associated Malodour In Vitro.

Although malodour formation on textiles and in washing machines has been reported to be a very relevant problem in domestic laundry, the processes leading to bad odours have not been studied intensively. In particular, the smell often described as “wet-and-dirty-dustcloth-like malodour” had not been reproduced previously. We developed a lab model based on a bacterial mixture of Micrococcus luteus, Staphylococcus hominis, and Corynebacterium jeikeium, which can produce this odour type and which might allow the detailed investigation of this problem and the development of counteractions. The model uses bacterial strains that have been isolated from malodourous textiles. We could also show that the three volatile compounds dimethyl disulfide, dimethyl trisulfide, and indole contribute considerably to the “wet-fabric-like” malodour. These substances were not only found to be formed in the malodour model but have already been identified in the literature as relevant malodourous substances.

Biodegradation of polycyclic aromatic hydrocarbons (PAHs) by bacterial mixture

Polycyclic aromatic hydrocarbons (PAHs) are widespread pollutants and they can cause cancer, abnormality and mutation. Nine natural PAHs-degrading bacteria were obtained from polluted areas. These bacteria and the bacterial mixture can degrade phenanthrene, anthracene, pyrene and benzo[a]pyrene. The bacterial mixture can increase the degradation rates of several PAHs compounds, such as phenanthrene and benzo[a]pyrene, during the repaired process, and the degradation rates of these compounds were over 83%. The efficient degradation of PAHs should be the cooperation of key enzymes, such as dioxygenase and dehydrogenase, in the bacterial mixture. The main accumulated metabolite of above four PAHs was dibutyl phthalate detected by gas chromatography mass spectrometry, indicating that the degradation process of PAHs mainly represented the phthalic acid pathway in this work. And the toxicity of PAHs could be decreased by biodegradation. The effects of cultural factors, such as culture time, temperature, metal ions and pH on PAHs degradation efficiency were also studied.

Interspecies interactions of Vibrio azureus and Jeotgalibacillus alkaliphilus on corrosion of duplex stainless steel

Investigations of multispecies biofilms and the relationships among these species are crucial for understanding the microbiologically influenced corrosion of metal alloys in actual environments. This study investigated the corrosion of 2205 duplex stainless steel by pure cultures of marine Vibrio azureus and Jeotgalibacillus alkaliphilus and their mixture using different electrochemical and surface analysis techniques. The results showed a significant enhancement of the growth rate and an increase in the biomass population of the biofilm in the presence of both bacteria. Microbial community analysis revealed a harsh competition between the two species. V. azureus benefitted from the competition between the two strains, grew faster, and dominated in the biofilm. Electrochemical results showed an increase in both the anodic dissolution and cathodic oxygen reduction rates of the duplex stainless steel in artificial seawater containing the bacterial mixture. The electrochemical behavior was similar in the presence the bacterial mixture and V. azureus alone, confirming that this bacterium acted as a dominant competitor. AFM images showed larger pits with irregular shapes in the presence of both bacteria, indicating faster pitting propagation.

Selection of rhizobacteria for biocontrol of Fusarium verticillioides on non-rhizospheric soil and maize seedlings roots

Fusarium verticillioides is a soil-borne plant pathogen of maize plants (Zea mays L.) responsible for major yield losses by causing root, stalk, and ear rot and quality losses due to mycotoxin accumulation on grains. Recently, biological control practices have proven to be effective in controlling plant pathogens and the selection of distinct biocontrol agents with new competitive abilities is essential since they characterize new pathogen control approaches. This study aimed to isolate maize rhizobacteria as potential biocontrol agents against F. verticillioides and to evaluate their effect on maize seedlings’ growth. Among several candidates, the isolates Bacillus safensis RF69, Bacillus sp. RP103 and Bacillus sp. RP242 were selected due to an intense in vitro antifungal ability. All individual rhizobacterial treatments and a Combined Bacterial Mixture (CBM) were effective in reducing fungal counts on non-rhizospheric soil and on maize seedling rhizosphere, as well as in improving seedling growth parameters in comparison to the control plants. Treatments with the isolate Bacillus sp. RP103 and the CBM showed the most promising results regarding fungal antagonism. Our results indicate that the prophylactic treatment of field soil and maize seeds with the individual or a consortium of the rhizobacterial isolates can be an effective strategy to reduce F. verticillioides’ density on soil and the rhizospheric contamination of maize seedlings. In addition, this is the first study that describes in vitro and in planta biocontrol of Fusarium verticillioides by B. safensis individually and in combination with other Bacillus spp., highlighting its potential biocontrol applications.

Randomised clinical trial: a 12-strain bacterial mixture versus faecal microbiota transplantation versus vancomycin for recurrent Clostridioides difficile infections.

A defined bacterial mixture could be a safer alternative to faecal microbiota transplantation (FMT). To compare the efficacy of a 12-strain mixture termed rectal bacteriotherapy with either FMT or vancomycin for recurrent Clostridioides difficile infection (CDI) in an open-label 3-arm randomised controlled trial. We screened all individuals positive for C difficile from May 2017 to March 2019. Persons with laboratory-confirmed recurrent CDI were included. Before FMT and rectal bacteriotherapy, we pre-treated with vancomycin for 7-14days. Rectal bacteriotherapy was applied by enema on three consecutive days and FMT by enema once with possible repetition for two to three infusions within 14days. The vancomycin group was treated for 14days with additional five weeks of tapering for multiple recurrences. The primary outcome was clinical cure within 90days. A secondary outcome was 180-day all-cause mortality. Participants in the FMT group (n=34) were cured more often than participants receiving vancomycin (n=31), 76% vs 45% (OR 3.9 (1.4-11.4), P<0.01) or rectal bacteriotherapy (n=31), 76% vs 52% (OR 3.0 (1.1-8.8), P=0.04). Rectal bacteriotherapy and vancomycin performed similarly (P=0.61). The mortality rate was 6% in the FMT group, 13% in the bacteriotherapy group and 23% in the vancomycin group. FMT tended to reduce mortality compared with vancomycin, OR 0.2 (0.04-1.12), P=0.07. Rectal bacteriotherapy appears as effective as vancomycin but less effective than 1-3 FMTs. FMT by enema with 1-3 infusions is superior to vancomycin for treating recurrent C difficile infections and might reduce mortality.

Antimicrobial Cocktail Combining Specific Peptide Extracts from Native Probiotic Bacteria Hamper Adulteration of Ready-to-Eat Mango Wedges

Consumption of ready-to-eat chopped fruits sold in the streets is a concern, as such activities are outside the regulation and protection in most developing countries. Ready-to-eat mangos are commonly sold as wedges in plastic cups at ambient temperature by mobile vendors in Ecuador, thus they are prone to contamination by bacteria, which poses a safety issue of concern. This work aimed to evaluate the effect of several antimicrobial cocktails consisting of previously designed specific peptide extract combinations from two probiotic bacteria Lactobacillus plantarum UTNCys5-4 and Lactococcus lactis subsp. lactis UTNGt28, along with nisin, a commercial food additive, on mango wedges artificially inoculated with a logarithmic phase culture of a five-strain bacterial mixture (FSBM). Preliminary bacteriological analysis of mango wedges purchased from mobile vendors showed the presence of multiple antibiotic-resistant isolates such E. coli spp., Enterobacter spp., Shigella spp., Salmonella spp., along with yeasts and molds, indicating non-compliance with the food safety standards. The results revealed that two antimicrobial cocktails, T2 and T5, containing cell-free supernatant based (CFS) and precipitated peptides (PP) based cocktails from UTNCys5-4 and UTNGt28 strains applied at dose 1:3 (v/v), were the most efficient combinations that inhibited the colonization of total bacterial counts with 56.03% and 55.61% in mango wedges stored with refrigeration. The reduction of total E. coli counts was 64.93%, while Salmonella and Shigella counts were reduced by 98.09% and 97.93%, respectively, when mango wedges were treated with T5-cocktail. The commercial nisin inhibited total Salmonella spp. counts by 40.13%, while E. coli spp. and Shigella spp. diminished by 28.20% and 37.22%, respectively. Moreover, we showed that T5 but not T7 (nisin) damaged the target cell integrity, thereby eventually inhibiting their growth and reproduction. The selected antimicrobial cocktails exerted a bacteriolytic effect by killing the FSBM simultaneously in a fruit matrix and preventing their accumulation in mango wedges. Furthermore, there is a possibility of using peptide combinatorial treatments to combat drug-resistant bacteria in ready-to-eat fruits.

Multistrain probiotics use in main commercially cultured freshwater fish: a systematic review of evidence

AbstractThis review aims to explore developments in the usage of multistrain probiotics in commercial freshwater‐cultured fish and to address factors that affect the efficacies of multistrain probiotics to enhance growth parameters, survival after bacterial infection and immune modulation in comparison to monostrain probiotics. From bibliographic searches in Scopus, Web of Science and PubMed, it was possible to select 81 articles that evaluated multistrain probiotics supplementation during in vivo trials in Nile tilapia (Oreochromis niloticus), rainbow trout (Oncorhynchus mykiss), common carp (Cyprinus carpio) and roho labeo (Labeo rohita). Most of the articles showed different benefits, including enhancement of fish growth performance, immune response and resistance against some pathogenic bacteria, such as Aeromonas hydrophila, Streptococcus agalactiae and Streptococcus iniae. However, only 13 journal articles included a monostrain probiotic as a control that would allow direct comparison with a probiotic bacterial mixture to determine if the mixture offered higher benefits in comparison to a monostrain probiotic and a control group without probiotic supplementation. Here we explain the main findings, including the best probiotic mixtures, and some perspectives on multistrain probiotics research and use on a commercial scale.

Fermentation of Ferulated Arabinoxylan Recovered from the Maize Bioethanol Industry

Maize by-product from the bioethanol industry (distiller’s dried grains with solubles, DDGS) is a source of ferulated arabinoxylan (AX), which is a health-promoting polysaccharide. In the present study, AX from DDGS was fermented by a representative colonic bacterial mixture (Bifidobacterium longum, Bifidobacterium adolescentis, and Bacteroides ovatus), and the effect of the fermented AX (AX-f) on the proliferation of the cell line Caco-2 was investigated. AX was efficiently metabolized by these bacteria, as evidenced by a decrease in the polysaccharide molecular weight from 209 kDa to &lt; 50 kDa in AX-f, the release of ferulic acid (FA) from polysaccharide chains (1.14 µg/mg AX-f), and the short-chain fatty acids (SCFA) production (277 µmol/50 mg AX). AX-f inhibited the proliferation of Caco-2 cells by 80–40% using concentrations from 125–1000 µg/mL. This dose-dependent inverse effect was attributed to the increased viscosity of the media due to the polysaccharide concentration. The results suggest that the AX-f dose range and the SCFA and free FA production are key determinants of antiproliferative activity. Using the same polysaccharide concentrations, non-fermented AX only inhibited the Caco-2 cells proliferation by 8%. These findings highlight the potential of AX recovered from the maize bioethanol industry as an antiproliferative agent once fermented by colonic bacteria.

A Gnotobiotic Model to Examine Plant and Microbiome Contributions to Survival under Arsenic Stress.

So far, the relative importance of the plant and its microbiome in the development of early stages of plant seedling growth under arsenic stress has not been studied. To test the role of endophytic bacteria in increasing plant success under arsenic stress, gnotobiotic seeds of J. montana were inoculated with two endophytic bacteria: Pantoea conspicua MC-K1 (PGPB and As resistant bacteria) and Arthrobacter sp. MC-D3A (non-helper and non-As resistant bacteria) and an endobacteria mixture. In holobiotic seedlings (with seed-vectored microbes intact), neither the capacity of germination nor development of roots and lateral hairs was affected at 125 μM As(V). However, in gnotobiotic seedlings, the plants are negatively impacted by absence of a microbiome and presence of arsenic, resulting in reduced growth of roots and root hairs. The inoculation of a single PGPB (P. conspicua-MCK1) shows a tendency to the recovery of the plant, both in arsenic enriched and arsenic-free media, while the inoculation with Arthrobacter sp. does not help in the recovery of the plants. Inoculation with a bacterial mixture allows recovery of plants in arsenic free media; however, plants did not recover under arsenic stress, probably because of a bacterial interaction in the mixture.

Identification of Collimonas gene loci involved in the biosynthesis of a diffusible secondary metabolite with broad-spectrum antifungal activity and plant-protective properties.

In greenhouse and field trials, a bacterial mixture of Collimonas arenae Cal35 and Bacillus velezensis FZB42, but not Cal35 alone or FZB42 alone, was able to protect tomato plants from challenge with the soilborne fungal pathogen Fusarium oxysporum f.sp. lycopersici (Fol). To identify genes and mechanisms underlying this property in Cal35, we screened a random transposon insertion library for loss of function and identified two mutants that were impaired completely or partially in their ability to halt the growth of a wide range of fungal species. In mutant 46A06, the transposon insertion was located in a biosynthetic gene cluster that was predicted to code for a hybrid polyketide synthase-non-ribosomal peptide synthetase, while mutant 60C09 was impacted in a gene cluster for the synthesis and secretion of sugar repeat units. Our data are consistent with a model in which both gene clusters are necessary for the production of an antifungal compound we refer to as carenaemins. We also show that the ability to produce carenaemin contributed significantly to the observed synergy between Cal35 and FZB42 in protecting tomato plants from Fol. We discuss the potential for supplementing Bacillus-based biocontrol products with Collimonas bacteria to boost efficacy of such products.

Evaluation of vitamin-producing and immunomodulatory lactic acid bacteria as a potential co-adjuvant for cancer therapy in a mouse model.

To evaluate a mixture of selected lactic acid bacteria (LAB) (a riboflavin-producer, a folate-producer and an immunomodulatory strain) as co-adjuvant for 5-fluorouracil (5-FU) chemotherapy in cell culture and using a 4T1 cell animal model of breast cancer. The viability of Caco-2 cells exposed to 5-FU and/or LAB was analysed. Mice bearing breast tumour were treated with 5-FU and/or LAB. Tumour growth was measured. Intestinal mucositis (IM) was evaluated in small intestine; haematological parameters and plasma cytokines were determined. The bacterial mixture did not negatively affect the cytotoxic activity of 5-FU on Caco-2 cells. The LAB mixture attenuated the IM and prevented blood cell decreases associated with 5-FU treatment. Mice that received 5-FU and LAB mixture decreased tumour growth and showed modulation of systemic cytokines modified by both tumour growth and 5-FU treatment. The LAB mixture by itself delayed tumour growth. The mixture of selected LAB was able to reduce the side-effects associated with chemotherapy without affecting its primary anti-tumour activity. This bacterial mixture could prevent the interruption of conventional oncologic therapies by reducing undesirable side-effects. In addition, this blend would provide essential nutrients (vitamins) to oncology patients.

DNA-SIP identification of phenanthrene-degrading bacteria undergoing bioaugmentation and natural attenuation in petroleum-contaminated soil

DNA-stable isotope probing (SIP) with 13C labeled phenanthrene (PHE) as substrate was used to identify specific bacterial degraders during natural attenuation (NA) and bioaugmentation (BA) in petroleum contaminated soil. BA, with the addition of a bacterial suspension mixture named GZ, played a significant role in PHE degradation with a higher PHE removal rate (∼90%) than that of NA (∼80%) during the first 3 days, and remarkably altered microbial communities. Of the five strains introduced in BA, only two genera, particularly, Ochrobactrum, Rhodococcus were extensively responsible for PHE-degradation. Six (Bacillus sp., Acinetobacter sp., Xanthomonas sp., Conexibacter sp., Acinetobacter sp. and Staphylococcus sp.) and seven (Ochrobactrum sp., Rhodococcus sp., Alkanindiges sp., Williamsia sp., Sphingobium sp., Gillisia sp. and Massilia sp.) bacteria responsible for PHE degradation were identified in NA and BA treatments, respectively. This study reports for the first time the association of Xanthomonas sp., Williamsia sp., and Gillisia sp. to PHE degradation.

Continuous biohydrogen production from poplar biomass hydrolysate by a defined bacterial mixture immobilized on lignocellulosic materials under non-sterile conditions

Lignocellulosic biowastes are rich in sugars and may be used as low-cost feed to produce environmentally friendly fuels such as hydrogen (H2). Poplar biomass is available in large quantities as a sugar-rich biowaste. Few studies have evaluated bacterial H2 production using well-defined mixed cultures (DMC) under non-sterile continuous culture conditions. DMC composed of high H2-producing bacteria may circumvent the potential risk of a single bacterial culture being out-competed under non-sterile conditions. The novelty of this study lies in the continuous production of H2 from poplar biomass using DMC in immobilized state under non-sterile conditions. Under optimized continuous culture conditions with DMC immobilized on coconut coir, a H2 yield of 2.83 mol/mol of hexose was steadily obtained over a period of 40 days, which was four-fold higher compared to that obtained with Bacillus thuringiensis. This approach may enable to meet the increasing demand for cleaner energy-rich fuels on a large-scale in a steady manner.

Potential Application of a Pseudomonas geniculata ATCC 19374 and Bacillus cereus EC3 Mixture in Livestock Wastewater Treatment

In this study, we isolated two bacterial strains, P2 (Pseudomonas geniculata ATCC 19374, P. geniculata ATCC 19374) and B1 (Bacillus cereus EC3, B. cereus EC3) from pig farm soil, which were mixed to construct a novel bacterial mixture (P2:B1 = 1:1). We studied the heterotrophic nitrification capablity and growth characteristics of bacterial mixture in heterotrophic nitrification medium (HNM). And the factors affecting the nitrogen removal of the bacterial mixture such as C/N ratio, NH4+-N load and inoculation size of the bacterial mixture were investigated in this study. Furthermore, we used the bacterial mixture to treat livestock wastewater to remove NH4+-N, TN and COD. The results showed that the optimal C/N ratio and inoculation size for the bacterial mixture were 12 and 5%, respectively. It is worth to mention that the bacterial mixture shows excellent NH4+-N removal ability under low C/N ratio, indicating that the bacterial mixture had the potential to be applied to wastewater with C/N lower than 8. When the initial NH4+-N concentration was 500 mg/L, the NH4+-N removal efficiency exceeded 90% with a 5% inoculation size of the bacterial mixture after 72 h. When the single bacteria and bacterial mixture were employed to treat livestock wastewater, the removal efficiencies of bacterial mixture on NH4+-N, TN and COD within 72 h were 70.06%, 58.12% and 81.48%, respectively, which were higher than that of single bacteria. The bacterial mixture has potential application value in enhancing the ability of reactors and constructed wetlands to remove pollutants from livestock wastewater and developing a novel and efficient biological nitrogen removal technology. Our current research provides a research basis for the application of the bacterial mixture in the future.

Acetochlor degradation by a mixed culture of P. fluorescens KT3 and B. subtilis 2M6E immobilized in alginate

In this study, the acetochlor degradation by two microbial isolates, P. fluorescens KT3 and B. subtilis 2M6E, was determined. The immobilization of the bacterial mixture in alginate beads resulted in higher degradation rates compared to their free cells. The addition of glycerol as a cryoprotectant reducing adverse effects in long-term storage. After storing at 4oC for three months, the cell survivals of free cell with and without the cryoprotectant were 43.0 ± 6.1% and 57.3 ± 5.9%, while data for immobilized bacteria were 64.0 ± 5.3% and 77.6 ± 4.0%, respectively. These results prove that the immobilization of bacteria in alginate and the addition of glycerol can be applied for storing bacteria in a long-term period.

Consortium of endophytic bacteria and rhizobacteria effectively suppresses the population of Pratylenchus coffeae and promotes the growth of Robusta coffee

Abstract. Asyiah IN, Mudakir I, Hoesain M, Pradana AP, Djunaidy A, Sari RF. 2020. Consortium of endophytic bacteria and rhizobacteria effectively suppresses the population of Pratylenchus coffeae and promotes the growth of Robusta coffee. Biodiversitas 21: 4702-4708. Pratylenchus coffeae as the coffee-parasitic nematode can cause a yield loss from 28.7% to 78.4% on Robusta coffee (Coffea canephora A. Froehner). Environmentally friendly and sustainable efforts can be made to control this nematode by applying the antagonistic agents from the bacterial group. The application of antagonistic agents in a consortium has a better effectivity than a single application. This study was aimed to identify the effectivity of the consortium of endophytic bacteria and rhizobacteria formulated on a cost-effective molasse medium against the P. coffeae population and growth of Robusta coffee in a greenhouse. A total of nine bacterial isolates of genus Bacillus and Pseudomonas were used during experiment. The formulation was prepared by mixing the bacterial suspension and 2% molasses with a ratio of 1:1 (v/v). The greenhouse assay was performed following the completely randomized block design pattern with five treatments and five replications. Robusta coffee plant clone BP 936 was treated with a 10 mL (109 CFU mL-1) bacterial consortium mixture while control was treated with 10 mL sterilized water. Each plant was inoculated with P. coffeae 50 J2 after a week of bacterial consortium application. The result showed that all bacterial consortiums were effective in suppressing the population of P. coffeae in soil and root of Robusta coffee. All consortiums gave a better result than control in suppressing the population of P. coffeae. The best suppression of nematodes was shown by the Cst 02 consortium with the suppression value of 62.5% in the root and 76.1% in the coffee plant rhizosphere. The application of bacterial consortium increases the plant height (28.02-44.51%), number of leaves (127.27-168.18%), and leaf area (278.8-425.57%). In this study, suppression of P. coffeae population by bacterial consortium showed a positive correlation with plant growth. This study presents the information of endophytic bacteria and rhizobacteria consortium from Bacillus and Pseudomonas group that is effective in suppressing the population P. coffeae and improves the growth of Robusta coffee.

Effect of a Dietary Mixture of Beneficial Bacteria on Growth Performance, Health Condition, Chemical Composition, and Water Quality of Nile Tilapia, Oreochromis niloticus Fingerlings

ABSTRACT Effects of dietary supplementation of Bifidobacterium longhum, Bifidobacterium thermophilum, Bacillus subtilis, and Lactobacillus acidophilus on growth performance, health condition, body chemical composition, and water quality of Nile tilapia (Oreochromis niloticus) fingerlings were evaluated. Five experimental treatments in triplicate were fed a diet containing 30% crude protein supplemented with variable inclusion of bacterial mixture: control, T1, T2, T3, and T4 containing 0, 1.0, 2.0, 3.0, and 4.0 g bacterial mixture/kg diet, respectively. Fish fed the T4 diet had the highest final body weight, weight gain, specific growth rate, thermal growth coefficient, feed intake, and the best feed conversion ratio. No significant differences in body chemical composition of fish were observed in terms of dry matter, crude protein, lipid, ash, and energy content among all treatments. Probiotic supplementation showed no noticeable differences on haematological and biochemical blood parameters, except for packed cell volume, albumin, albumin/globulin ratio, aspartate transaminase, glucose, uric acid, triglycerides, and cholesterol. Conclusively, Nile tilapia fingerlings diet supplemented with evaluated probiotic with an optimal dietary supplementation of 4 g/kg diet improved growth performance and fish health without a negative impact on water quality. This supplementation could therefore be used as a probiotic in Nile tilapia fingerlings diet.