Growth, sporulation and larvicidal activity of Bacillus sphaericus

Characterization and biological activity of a brazilian isolate of Bacillus sphaericus (Neide) highly toxic to mosquito larvae

“…The use of MBS medium to grow B. sphaericus S2 and 2362 in this study confirms previous observations about the efficacy of such a complex medium to produce larvicidal strains of B. sphaericus with high toxin yields (Kalfon et al 1983). It was noticed, however, that a rather high level of foam was generated during exponential growth phase, and in late sporulation stage (lysis of sporangium).…”

“…Growth in fermentor -A loopfull of lyophilized culture of each strain was seeded into 250 ml Erlenmeyer flasks with 50 ml of MBS medium (Kalfon et al 1983) which contains per liter tryptone 10 g, yeast extract 2 g, MgSO 4 0.3 g, CaCl 2 0.2 g, Fe 2 (SO 4 ) 3 0.02 g, MnSO 4 0.02 g and ZnSO 4 0.02 g. Cultures were incubated in G25 New Brunswick rotary shakers at 30 o C, 250 rpm. At late exponential phase, 100 ml of culture was inoculated into a New Brunswick 14 liter fermentor with 10 liters of MBS broth (1% v/v).…”

Selection and characterization of Bacillus thuringiensis isolates with a high insecticidal activity against Spodoptera frugiperda (Lepidoptera: Noctuidae)

“…The isolates were obtained from rural region the Darcinópolis (6°43'7'' S: 47°45'10'' W), Guaraí (8°50'4'' S: 48°30'36'' W), Santa Rita (10°51'44'' S: 48°54'27'' W), Cariri (11°53'25'' S: 49°9'49'' W), Gurupi (11º43'45" S; 49º04'07" W), Sucupira (12°0'57'' S: 48°56'6'' W), Sandolândia (12°31'37'' S: 49°56'7'' W), Araguaçú (12°55'51'' S: 49°48'59'' W), São Salvador (12°44'36'' S: 48°14'20'' W) and Palmeirópolis (13°2'36'' S: 48°24'11'' W) (Figure 1). The soil samples were screened for Bt on petri dishes with a selective NYSM medium (KALFON et al, 1983) containing 100 mg/L penicillin G grown for 24 h at 30 ± 0.5°C at 180 rpm. After this period, each sample was individually analyzed and identified by phase contrast microscopy (× 1000), to verify the presence of inclusion bodies and crystals that allow for the differentiation between B. thuringiensis and Bacillus cereus (FRANKLAND; FRANKLAND, 1887).…”

Development of a Cheap Media for Bacillus thuringiensis Growth

“…Bacillus is a gram positive, aerobic, spore forming soil bacterium that has been used in recent years as a microbial larvicide, to control mosquito vector populations [16]. It shows major toxic effect against larvae of filariasis (Culex) and malaria(Anopheles) vectors [13].…”