Gram-negative bacteria bacilli

Figures 9 shows the inhibition of control starch film, starch/chitosan composite film (S C 9 1), and Starch/Chitosan nanocomposite (S C 9 1+2 %CNF) film toward bacteria Bacillus subtilis (left) and Escherichia coli (right). Control starch film showed no inhibition toward both bacteria Bacillus subtilis and Escherichia coli, in fact, there were colonies of bacteria formed under the film. It shows that the control starch film is not able to inhibit bacteria. In general, Starch/Chitosan composite (S C 9 1) film demonstrates inhibition toward both Gram-positive and Gram-negative bacteria, Bacillus subtilis and Escherichia coli.

These compounds showed a remarkable activity toward Gram-positive (e.g.. Bacillus cereus, Staphylococcus aureus, Sarcina luted) and Gram-negative bacteria (e.g.. Pseudomonas sp.) the activity was somewhat lower in the styryl derivatives (82MI2). 

Polymyxin B Bacillus polymyxa Gram-negative bacteria Cell membrane... 

Benzylpenicillin or penicillin G has a narrow antimicrobial spectrum. It is active with respect to Gram-positive bacteria (staphylococcus, streptococcus, and pneumococci), causative agent of diphtheria, and anthrax bacillus. Gram-negative bacteria are resistant to it. Benzylpenicillin is broken down by stomach acid and destroyed by staphylococcus penicillinase. 

Although the Cu-type family of nitrite reductase is comprised of soluble enzyme and localized in the periplasmic space in gram-negative bacteria, it has proved to be a membrane-bound enzyme in denitrifying Bacillus, which is gram positive and lacks an outer membrane and periplasmic space (Denariaz et ai, 1991 Urata and Satoh, 1991 Ho etal., 1993). 

Enteric diseases of pigs and cattle are due to several species of Gram-negative bacteria, e.g. by overproliferation of the natural gut bacillus Escherichia coli, or by Salmonella species, e.g. S. dublin or S. typhimurium. The pathology thus caused consists of severe diarrhoea or scouring . Adequate control of Salmonella bacteria is a serious public health problem. 

Newly synthesized compounds 22, 23, 25c-e, 26d and 29e were screened in vitro for their antimicrobial activities against Gram positive bacteria Staphylococcus aureus (NCTC-7447), Bacillus cereus (ATCC-14579) and Gram negative bacteria Serratia marcesens (IMRU-70) and Proteus merabitis (NTCC-289) using the paper disk diffusion method for the antibiotic sensitivity technique [60]. The tested compounds were dissolved in N,N-dimclhylformamidc (DMF) to obtain a 1 mg/mL solution. The inhibition zones of microbial growth produced by different compounds were measured in millimeters at the end of an incubation period of 48 h at 28 °C. DMF alone showed no inhibition zone. 

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